26760 - cover 620x297 - acl race series · 8 1 features • lightweight design for improved engine...

8

1

FEATURES• Lightweight design for improved engine

acceleration and lower bearing loads

• 30% Stronger than original pistons

• High silicon aluminium for high strength and lowexpansion

• All have pressure balancing grooves

• Lightweight tapered pins

• High strength moly filled or nitrided steel top rings

• Long rod versions reduce weight further

• Stroker versions for greater capacity

• Suitable for Street, moderate track, sprint and marine

• Low friction rings

• In most cases eliminate need for forgings

Automotive Components Limited MAHLE-ACL ACL Bearing Company ACL Gasket CompanyLevel 8, 390 St Kilda Road Piston Products 253-293 George Town Road Cnr Acacia & Bunya StreetsMelbourne 2-8 Oxford Road Rocherlea Eagle FarmVictoria 3004 Laverton North Tasmania 7248 Queensland 4009Phone: (03) 9285 4000 Victoria 3026 Phone: (03) 6324 4600 Phone: (07) 3365 0700Fax: (03) 9866 4300 Phone: 1300 363 356 Fax: (03) 6326 6666 Fax: (07) 3268 6662ABN: 51 006 542 785 *Orders Only

AUGUST 2003

“AUSTRALIAN ENGINEERING EXCELLENCE”

TSD3Technical Hotline: 1800 033 113 (Piston and Ring only) http:/www.acl.com.au

A.C.N. 006 542 785

AutomotiveComponentsLimited

6. The pins must be fitted to heated rods. The rod eyemust be in good condition and must never be overheated,either generally, or in any one spot. Use a or heavy oil ormoly based grease to lubricate the pin bore at the time ofassembly. Use heat crayons to ensure rod eyes are notoverheated. Always check for freedom of movement afterthe assembly has cooled down. Always relubricate thepin with heavy oil or a moly and oil mixture to preventseizure on start up. It takes a long time for oil to reach thispoint even if the engine is primed first, (as it should be).

7. The rings and skirts should be lubricated with lightengine oil prior to assembly and ACL bolt protectorsused to prevent the rod bolts damaging the crankshaft.

8. Honing for performance engines: Best results will beachieved if a deck plate is used to neutralise the effectsof head bolt tension on bore distortion. Obtain a smoothsurface finish by honing to size with a 210 to 320 gritstone and finally finishing with 400 grit or better (flexiblehoning or stone) to achieve a plateau. For further detailsrefer to ACL Bore Finishing Guide. Clean bores with hotsoapy water and nylon brush and swab with clean engineoil. Do not use petrol or kerosene, neither will clean thebores properly. Finally, always check cleanliness with aclean white cloth which must not come out grey!

9. Modifying pistons: All of the versions mentioned here(except 9353) are finished pistons and should need nofurther modification. However should any minor crownmilling or machining be needed to achieve specificcompression heights and compression ratio then caremust be taken to avoid very thin sections between thetop of the crown and the underhead. A minimumthickness at any one point of 6 mm should be retainedand general head thickness 7 mm. Top land height (fromthe top ring to the top of the piston (or valve cut out inthe case of the Ford pistons) should never be less than 4mm). Care must be exercised when gripping the pistonto avoid damage and skirt distortion. A mandrelmachined to support the piston on its spigot register (atthe open end) plus pin pull back should be used forcrown face turning and the piston clamped on its crownfor milling. If balancing is required metal must NOT beremoved from below the pin bosses.

10 Valve Clearance: When enlarged valves or higher liftcamshafts are used the valve to piston clearence MUST bechecked using plasticine in a trial build. In any case valveto piston clearence may still need adjustment for some ofthe non-standard applications listed in this bulletin.

11 Tuning your engine: Increasing compression ratio of anyengine will require changes to the tuning of the engine, inparticular the ignition, air fuel ratio and spark plugs.There are many specialist books on this subject. Withincreased compression ratio it is inevitable that while theinitial advance setting may be the same, the advancecurve will need to be adjusted to reduce the amount ofmechanical (and vacuum if any) advance. Air fuel ratio isalso important and with any increase in output it is

essential that leaning out at high RPM is avoided. Soslightly richer mixtures may be needed. Colder heatrange spark plugs may also needed depending upon thedegree of modifications and anticipated usage. Adviceshould be sought from spark plug manufacturers.

12. Finally it goes without saying that the accessoriessuch as distributor, coil and leads, all fuel systemcomponents, water pump and cooling system mustbe in excellent condition in any performanceapplication. Depending upon the extent ofmodifications the cooling system may well requireupgrading since the output from the modified enginemay require more cooling than was available from thestandard components.

Where to measure clearance

Measure clearance in line with internal rib for any pistonmarked "BOT" or "RIB" also known as "Band", or “Mid” ifspecified. Never measure across the tails of a piston.

Measure piston diameter in line with internal rib.

Warranty: ACL Performance and RACE brand pistonassemblies.

ACL Performance range and "RACE" brand pistonassemblies with "9000" series part numbers are designed toenable specialist engine builders to obtain moderateincreases in compression ratio and engine speeds forotherwise standard engines. These pistons are not designedfor use in forced induction (i.e. supercharged orturbocharged) engines or for use with fuels other thanleaded or unleaded pump petrol and 100 octane aviationgasoline. ACL does not provide any implied or expresswarranty on products used in engines over whose design ithas no knowledge or control and users must acceptresponsibility for use in non standard applications includingany use in engines used in competition or where exhaustemissions regulations apply. ACL reserves the right to makeproduct changes without notice and without incurring anyliability for similar products previously manufactured.

Nigel TaitChief EngineerAutomotive Components Limited

14

Need other Information?(1) Dial (03) 9866 4349 for information in Techfax or on the internet, www.acl.com.au

(2) For piston and ring Technical enquiries telephone 1800 033 113(3) For gasket Technical enquiries telephone 1800 777 149

(4) For bearing enquiries (03) 6324 4600

The information in this publication has been compiled from the most reliable sources available. Although all care has been taken in preparing and researching thisinformation, we cannot be responsible for any errors that may occur. All information in this publication is copyright and reproduction in whole or part is not permittedwithout the written consent of Automotive Components Limited A.C.N. 006 542 785

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9

MeasurehereMid

ORRib

PISTONS AND ENGINE REBUILD KITS

Chevrolet – 350, 383

Ford – 250, EA, EB-EL 4 Litre

Ford – Cleveland 302/351, 377

Ford – Cleveland Long Rod 351

Ford – Windsor 289, 302

Ford – Windsor Stroker 347

Holden 202, 253, 304, 308, 355, V6

where the engine is close to its original specification but isused for mild extensions of the originally envisaged power,torque and speed. They are NOT intended to displace forgedpistons in out and out racing applications where output wellin excess of 100 BHP per litre is expected. See also warrantynotes elsewhere in this bulletin.

Supercharging or turbocharging

Forced induction engines generally require significantreduction to the compression ratio to prevent severedetonation. ACL's Performance range pistons have higher compression ratio than standard. Consequentlythese pistons are not intended to be used withsuperchargers or turbochargers.

Avoid Detonation!

As with any piston, performance or otherwise, detonation isextremely harmful and will inevitably lead to failure. Caremust be taken to avoid this by careful tuning and correctselection of petrol octane relative to the compression ratio ofthe special engine, spark plug heat range and fuel andignition settings. Also remember that any performanceengine will develop more power than the original andtherefore more heat rejection to the cooling system. Thecooling system must therefore be reviewed to make sure ithas adequate capacity to cope with the higher loading.

Assembly and installation hints

1. Clearance: ACL's high silicon alloy enables lowclearances to be run and this improves ring sealing dueto better control over the piston's movement in the bore.The clearance marked on the top of each piston is therecommended minimum only and extra clearance mustbe given for engines where considerably more powerthan the standard is expected and when continuous highspeed operation is needed. Also if the compression ratiois increased further than by the difference of the pistonover the standard piston (e.g. by block or head milling, oruse of small combustion chamber heads), then an extra0.001" or so will be needed. For marine use allow anextra 0.001" then a little more depending on the severityof use or degree of other modifications.

2. Check squish height. This is the distance from the topsurface of the piston to the corresponding flat part of thehead's surface. Adjust block height if necessary to givearound 0.040" which will mean in most cases the pistonbeing at or near the deck face at TDC. Too little squishheight could result in the piston touching at high speed.Too much will lessen the squish effect and could lowerthe maximum compression ratio that can be used for thegiven fuel before detonation occurs.

Measure the deck height at TDC with a depthmicrometer.

3. Compression ratio: The tabulation shows the nominalcompression ratios which will be achieved if the newpistons are used in conjunction with standard bore sizesand standard blocks and heads.

As earlier mentioned the increases over standard areapproximately 1 ratio. Any further increases due to heador block machining are at the risk and responsibility ofthe user bearing in mind that the pistons are most likelyto be used on pump petrol (or possibly 100 octaneAvgas). DO NOT EXCEED 10.0:1. No piston is immune tothe effects of detonation.

Measuring cylinder head bowl volume with a burette.

4. Check ring gaps and adjust file back top rings ifsupplied. Do not strive for very small gaps especially forhigh compression ratios or continuous high speed. It isbetter to have a little too much than to run the risk ofbutting (which will seize the whole piston). A gap of lessthan 0.016" should seldom be necessary and theadvantage gained in having smaller gaps is minimal. Formost performance 4” Applications an initial gap of 0.020’will be an ideal starting point. When filing gaps it is bestto hold a small sharp single cut file in the vice and holdthe ring in your hands when filing. File only one side ofthe gap using the other side as a guide to keep thefinished gap square. Deburr but do not file any chamferon the outer edge, this will increase blowby at this point.The second rings in file back sets are not file back type.For performance engines second rings should have alittle more gap than the top rings, certainly never less ortop ring flutter may be induced at high RPM.

5. Assemble all rings according to the instructionssupplied and check back clearance, and that the secondrings are fitted with the dots upwards. Mixing brands ofrings and pistons is not recommended because thetolerances on side clearance and back clearance maynot be compatible.

13

9490

Flat Top high compression

5.625”142.87mm

34.2mm

43.6mm1.710”

9.4

0

0

9.3:1 @ 78cc

565gm120

R3326T-STDM23.55mm / 0.927”

M9106STD, 020,030, 040, 060

1.5, 1.5, 4.0

M9110005, 025, 035, 045, 065

8MKRY9490020, 030, 040, 060

8MKRY9490H020, 030, 040, 060

9570

‘D’ Bowlhigh compression

Left & Right versions5.625”

142.87mm

27.6mm

38.31.508”

7.7

3

17cc

9.5:1 @ 85cc

475gm120

R3326T-STDM23.55mm / 0.927”

M9106STD, 020,030, 040, 060

1.5, 1.5, 4.0

M9110005, 025, 035, 045, 065

8MKRY9570STD, 020, 030, 040, 060

8MKRY9570HStd, 020, 030, 040, 060

Not Suitablefor 91 unleaded

(98 Recommended)

9571

Round Bowlreduced compression

5.625”142.87mm

27.6mm

38.3mm1.508”

5.7

5

24cc

8.8:1 @ 91cc

470gm (020)120

R3326T-STDM23.55mm / 0.927”

M9106STD, 020,030, 040, 060

1.5, 1.5, 4.0

M9110005, 025, 035, 045, 065

8MKRY9571STD, 020, 030, 040, 060

8MKRY9571HStd, 020, 030, 040, 060

Suitable for91 Unleaded

9500


5.625”142.87mm

34.2mm

43mm1.690”

8.8

0

0

9.3:1 @ 76cc

555gm128

R3326T-STDM23.55mm / 0.927”

M9106STD, 020,030, 040, 060

1.5, 1.5, 4.0

M9110005, 025, 035, 045, 065

8MKRY9500STD, 020, 030, 040, 060

8MKRY9500HStd, 020, 030, 040, 060,

2

BASE PART NUMBER

DESCRIPTION

Rod Length

Pin C/L to U/Head(Note 1)

COMPRESSIONHEIGHT

(PIN C/L TO TOP)

CROWN THICKNESS(nominal, excludes rib)

* see NOTE 1

BOWL (Pocket) DEPTH

CROWN VOLUME(INC. VALVE RECESSES)

COMPRESSION RATIO AT TOTAL

CLEARANCE VOLUME(* see NOTE 3)

WEIGHT BARE (STD)PIN WEIGHT (NOM.)

PIN PART NUMBERPIN DIAMETER

RING SET(PRE-GAPPED)

WIDTH (mm)

RING SET(FILE BACK)

KIT NUMBER WITH PRE-GAPPED RINGS

KIT NUMBER WITHFILE BACK RINGS

ADDITIONAL NOTES

APPLICATIONS AND DATA

NOTE 1: Crown Thickness and Under Head excludes Rib and Any Valve Pocket but Includes BowlNOTE 2: Even number engine bank on driver’s side

ENGINEHOLDEN 308

Leaded Petrolto 1985

HOLDEN 4.9Unleaded Petrol

from 1987

HOLDEN Stroker to355 with Holden Rod

and 3.480” Crank—forAvgas/Super

HOLDEN 5.7 HSV or Stroker to 355 withHolden Rod and 3.480”

Crank—Super/ULPHolden202. Red RAC9096DBB1 6MKRY9096-030 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTR2.2cc Bowl RAC9096EBB1 6MKRY9096-040 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTR

RAC9096FBB1 6MKRY9096-060 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTR

Holden202. Red (Flat Top) RAC9118DBB1 6MKRY9118-030 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTR

RAC9118EBB1 6MKRY9118-040 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTRRAC9118FBB1 6MKRY9118-060 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTR

Holden202. Blue, Black RAC9096DBB2 6MKRY9096-030 6BHP2380-010 7MHP2398-010 4C5116-STD FH110GTR BH110GTR

RAC9096EBB2 6MKRY9096-040 6BHP2380-010 7MHP2398-010 4C5116-STD FH110GTR BH110GTRRAC9096FBB2 6MKRY9096-060 6BHP2380-010 7MHP2398-010 4C5116-STD FH110GTR BH110GTR

Holden3.8 V6 High Comp RAC9380CBB1 6MKRY9380-020 6B2360-010 4M2362-010 4C5106-STD GR721GTR BR720GTRVN (5/88-11/90) RAC9380EBB1 6MKRY9380-040 6B2360-010 4M2362-010 4C5106-STD GR721GTR BR720GTR23.6cc Bowl

Holden3.8 V6 High Comp RAC9380CBB2 6MKRY9380-020 6B2306-010 4M2302-010 4C5106-STD GW940GTR BW940GTRVN, VP (11/90-1/94) RAC9380EBB2 6MKRY9380-040 6B2306-010 4M2302-010 4C5106-STD GW940GTR BW940GTR23.6cc Bowl

Holden3.8 V6 High Comp RAC9380CBB3 6MKRY9380-020 6B2306-010 4M2309-010 4C5106-STD GW940GTR BW940GTRVR 23.6cc Bowl RAC9380EBB3 6MKRY9380-040 6B2306-010 4M2309-010 4C5106-STD GW940GTR BW940GTR

Holden253. Red RAC9115DBB1 8MKRY9115-030 8BHP2356-010 5MHP2357-010 5C5146C-STD FX130GTR AX130GTR

RAC9115FBB1 8MKRY9115-060 8BHP2356-010 5MHP2357-010 5C5146C-STD FX130GTR AX130GTR

Holden253. Blue, Black RAC9115DBB2 8MKRY9115-030 8BHP2356-010 5MHP2357-010 5C5146C-STD FX133GTR AX130GTR



RAC9500EBB1 8MKRY9500-040 8BHP2356-010 5MHP2357-010 5C5146C-STD FX142GTR AX140GTRRAC9500FBB1 8MKRY9500-060 8BHP2356-010 5MHP2357-010 5C5146C-STD FX142GTR AX140GTR



Holden355. Red RAC9355DAA1 8MKRY9355-030 8B663H-STD 5MHP2357-STD 5C5146C-STD FX142GTR AX140GTR(Stroker Round Bowlusing Chev conrods)

Holden4.9L. (Flat Top) RAC9490DBB1 8MKRY9490-030 8BHP2356-010 5MHP2357-010 5C5146C-STD GS150GTR BS150GTR

RAC9490EBB1 8MKRY9490-040 8BHP2356-010 5MHP2357-010 5C5146C-STD GS150GTR BS150GTR

Holden5.7L. 17cc “D” Bowl RAC9570DBB1 8MKRY9570-030 8BHP2356-010 5MHP2357-010 5C5146C-STD GS150GTR BS150GTR

Holden5.7L 23.8cc Bowl RAC9571CBB1 8MKRY9571-020 8BHP2356-010 5MHP2357-010 5C5146C-STD GS150GTR BS150GTR

RAC9571DBB1 8MKRY9571-030 8BHP2356-010 5MHP2357-010 5C5146C-STD GS150GTR BS150GTR

REBUILD KIT REBUILD KIT CONTENTS Full CylAPPLICATION NUMBER Piston & Ring Con Rod Main Cam Gasket Head

Kit Bearings Bearings Bearings Set Gasket

* How to use the Rebuild Kit Part No. RAC 9096 D B B 1to identify contents: eg. RAC9096DBB1 Rebuild Kit Application Piston & Ring Big End Mains Gasket

eg. Holden 202 O/Size U/Size U/Size Version

R A C E S E R I E S A P P L I C A T I O N A N D C O M P O N E N T L I S T I N G





Chevrolet350. (Flat Top with RAC9350DBB1 8MKRY9350-030 8B663H-010 5M909H-010 5C3349C-STD FP400GTR AF830GTRSingle Valve Recess) RAC9350EBB1 8MKRY9350-040 8B663H-010 5M909H-010 5C3349C-STD FP400GTR AF830GTR

Chevrolet350. (20cc “D” Bowl) RAC9352DBB1 8MKRY9352-030 8B663H-010 5M909H-010 5C3349C-STD FP400GTR AF830GTR

Chevrolet350. (Flat Crown RAC9353DBB1 8MKRY9353-030 8B663H-010 5M909H-010 5C3349C-STD FP400GTR AF830GTRNo Valve PocketsSemi-finished)

Ford302 Windsor RAC9302SDBB1 8MKRY9302S-030 8B634H-010 5M590H-010 5C5616C-STD FG971GTR BD870GTR(Flat Top) RAC9302SEBB1 8MKRY9302S-040 8B634H-010 5M590H-010 5C5616C-STD (Pre EFI) BD870GTR

Ford302, 351 Cleveland RAC9351DBB1 8MKRY9351-030 8B927H-010 5M91470-010 5C5696-STD GC230GTR AW980GTR(Flat Crown with RAC9351EBB1 8MKRY9351-040 8B927H-010 5M91470-010 5C5696-STD GC230GTR AW980GTRValve Pockets)

Ford351 Cleveland RAC9356CBB1 8MKRY9356-020 8B927H-010 5M91470-010 5C5696-STD GC230GTR AW980GTR(Flat Top Using 6” RAC9356DBB1 8MKRY9356-030 8B927H-010 5M91470-010 5C5696-STD GC230GTR AW980GTR302 conrods)* *(Supercedes RAC 9357)

Ford377 Cleveland RAC9377DBB1 8MKRY9377-030 8B7110-010 5M91470-010 5C5696-STD GC230GTR AW980GTR(Flat Top using (Duraglide)Stroker Chev conrods)

Ford377 Cleveland RAC9378DBB1 8MKRY9378-030 8B7110-010 5M91470-010 5C5696-STD GC230GTR AW980GTR(10cc Bowl Version (Duraglide)using Stroker Chevconrods)

Ford 3.9 EA, EB RAC9390CBB1 6MKRY9390-0.50 6BHP2150-010 7MHP2158-010 GR520/1GTR BR520GTR

RAC9390EBB1 6MKRY9390-1.00 6BHP2150-010 7MHP2158-010 GR520/1GTR BR520GTR

Ford 4.0 EB2, ED, EF, EL RAC9400CBB1 6MKRY9400-0.50 6BHP2150-010 7MHP2158-010 GR522GTR BR520GTR

RAC9400EBB1 6MKRY9400-1.00 6BHP2150-010 7MHP2158-010 GR522GTR BR520GTR

Ford4.1/250 RAC9410CBB1 6MKRY9410-020 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR(Flat Top) RAC9410DBB1 6MKRY9410-030 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR

RAC9410EBB1 6MKRY9410-040 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR

Ford4.1/250 RAC9411CBB1 6MKRY9411-020 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR(8cc Bowl Version) RAC9411DBB1 6MKRY9411-030 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR


Ford4.1/250 RAC9412CBB1 6MKRY9412-020 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR(Using 200 conrod RAC9412DBB1 6MKRY9412-030 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR8.6cc Bowl) RAC9412EBB1 6MKRY9412-040 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR

Ford4.1/250 RAC9413CBB1 6MKRY9413-020 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR(Using 200 conrod, RAC9413DBB1 6MKRY9413-030 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTRFlat Top 2 Ring Piston) RAC9413EBB1 6MKRY9413-040 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR

(NOTE—NOT ALL PISTONS IN THIS SERIES AVAILABLE IN REBUILD KITS)

11 12

3

9380

Bowl

6.38”162.05mm

21.75mm

36.3mm*1.429”

9.75

5.4

23.6cc

VN 9.6:1 @ 73.5ccVR 9.9:1 @ 71cc

462gm105

R3360T-STDM23.01mm / 0.906”

M1812020, 040

1.2, 1.5, 3.0

N/A

6MKRY9380020, 040

N/A

*Reduced to 36.3 to suit SCRA formula

HOLDEN V6VN-VR

9352

Central Bowl(was originally a ‘D’ Bowl)

5.565”141.35mm

27.6

39.4mm1.553”

7.3

6.5

20cc

9.0:1 @ 91cc

506 (030)120

R3326T-STDM23.55mm / 0.927”

M9106STD, 020,030, 040, 060

1.5, 1.5, 4.0

M9110005, 025, 035, 045

8MKRY9352030, 040

8MKRY9352H030, 040

2 Valve Pockets, Left andRight versions

9353

Flat Crownsemi-finished

5.7”144.78mm

27.6

41.10mm*1.618”

13.5 (S.F.)

0

0

9.3:1 @ 88cc

560gm (S.F.)120

R3326T-STDM23.55mm / 0.927”

M9106030, 040, 0601.5, 1.5, 4.0

M9110005, 025, 035, 045, 065

8MKRY9353030, 040

8MKRY9353H030, 040

*Increasedfrom 39.6 to allow

more options

9350

Flat Topwith single valve recess

5.7”144.78mm

31mm

39.6mm1.561”

8.6

4.9

3cc

9.3:1 @ 88cc

515gm 120

R3326T-STDM23.55mm / 0.927”

M9106STD, 020,030, 040

1.5, 1.5, 4.0

M9110005, 025, 035, 045, 065

8MKRY9350020, 030, 040

8MKRY9350H020, 030, 040

Note: Pistons marked ‘O’ & ‘E’ for odd & even

cylinders, Note 2


NOTE 3: Indicative Values only—Comp. Ratio = (Swept Volume + Clearance Volume) / Clearance Volumewhere Swept Volume = (3.14 x Bore2 x Stroke) / 4

Total Clearance Volume = Head + Piston + Gasket + Deck Volume—DO NOT EXCEED 10.0:1

9355

Central Bowl2 Valve Pockets, Left and

Right versions5.7”

144.78mm

23.4

36.4mm1.433”

7.0

6.5

20cc

9.0:1 @ 91cc

484 (030)120

R3326T-STDM23.55mm / 0.927”

M9122030, 040, 0601.2, 1.5, 3.0

N/A

8MKRY9355030, 040, 060

N/A

* Using Chev 400 Crankand 5.7” Rods

CR = 10.2:@86.8

HOLDEN 350Stroker with Chev 400

Rods and 3.480” Crank(also Chev Low comp. truck)

HOLDEN 355 StrokerUsing 5.7” Chev Rod

and 3.480” crankAlso Chev 383*

CHEV 350Small Block

(also Holden 308 or 304stroked to 330)

CHEV 350Semi-finished

9302S

Flat Crown with singlevalve pocket marked

‘L’ and ‘R’5.090”*

129.28mm

31mm

40.84mm1.608”

9.84

4.2

2.4cc

9.2:1 @ 77cc

558gm (020)115

R3340T-STDM23.17mm / .912”

M9106020, 030, 0401.5, 1.5, 4.0

M9110025, 035, 045

8MKRY9302S020, 030, 040

8MKRY9302SH020, 030, 040

*289 Rod Length5.154”/130.9

Skirt Coating from May 2002

9354

Bowl and valve pockets

5.778”146.76mm

27.6

41.6mm1.640”

9.0

5.5

22cc

8.4:1 @ 99cc(Based on 61cc head)

520gm (030)115

R3340T-STDM23.17mm / .912”

M9106030

1.5, 1.5, 4.0

M9110035

8MKRY9354030

8MKRY9354H030

4


BASE PART NUMBER

DESCRIPTION

Rod Length


COMPRESSIONHEIGHT

(PIN C/L TO TOP)


* see NOTE 1

BOWL (Pocket) DEPTH


COMPRESSIONRATIO AT TOTAL


WEIGHT BARE (STD) PIN WEIGHT (NOM.)


RING SET(PRE-GAPPED)WIDTHS (mm)

RING SET(FILE BACK)



ADDITIONAL NOTES


9377

Flat Crown with valvepockets

5.7”144.78mm

34.2

41.6mm1.640”

7.4

2.3

2cc

9.6:1 @ 89.8cc

540gm (030)120

R3326T-STDM23.55mm / .927”

M9106030

1.5, 1.5, 4.0

M9110035

8MKRY 9377030

8MKRY9377H030

ROD BEARING SET8B7110 STD/010 AVAILABLETO SUIT NARROWED RODS

ENGINEFORD 289and 302

Windsor Carb and EFI

FORD CLEVELAND377 Using 5.7”

Chev Rod

FORD CLEVELAND351 Low Comp. for

Small Chamber Heads

9351

Flat Crown with valvepockets

5.778”146.76mm*

34.2

41.9mm1.650”

7.7

2.3

2cc

351 3029.1:1 @ 90cc 9.1:1 @ 77cc

530gm115

R3340T-STDM23.17mm / .912”

M9106STD, 020,030, 040, 060

1.5, 1.5, 4.0

M9110005, 025, 035, 045, 065

8MKRY9351STD, 020, 030, 040, 060

8MKRY9351HSTD, 020, 030, 040, 060

*302 Rod Length6.030”/153.16

FORD CLEVELAND302/351

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9411

Bowl

5.88”149.35mm

28.7mm

38.86mm

8.36

1.8

8cc

9.7:1 @ 80cc

488115

R3340T-STDM23.17mm / .912”

M9123020, 030, 0401.5, 1.5, 4.0

M9121025, 035, 045

6MKRY9411020, 030, 040

6MKRY9411H020, 030, 040


9410

Flat top

5.88”149.35mm

28.7mm

38.86mm

10.16

0

0cc

10.6:1 @ 72cc

509115

R3340T-STDM23.17mm / .912”

M9123020, 030, 0401.5, 1.5, 4.0

M9121025, 035, 045

6MKRY9410020, 030, 040

6MKRY9410H020, 030, 040


Clearance Volume = Head + Piston + Gasket + Deck Volume—DO NOT EXCEED 10.0:1

9356

Flat Crown with valve pockets

6.030”153.16mm

27.6

35.9mm1.412”

8.3

2.3

2cc

9.9:1 @ 82cc

480gm (020)115

R3340T-STDM23.17mm / .912”

M9122020,030

1.2, 1.5, 3.0

Not Available

8MKRY9356020, 030

Not Available

3 RING VERSION RE-INTRODUCED WITH LARGER

2ND RING LAND (SEE P10)(M9125 SUITS SUPERSEDED 9357)

9378


5.7”144.78mm

34.2

41.6mm1.640”

6.0

2.3/1.4 (Bowl)

10cc

8.9:1 @ 97.8cc

520gm (030)120

R3326T-STDM23.55mm / .927”

M9106030

1.5, 1.5, 4.0

M9110035

8MKRY9378030

8MKRY9378H030


9379


5.7”144.78mm

27.6

41.6mm1.640”

9.0

5.5

20cc

9.0:1 @ 98cc

556 (030)120

R3326T-STDM23.55mm / .927”

M9106030

1.5, 1.5, 4.0

M9110035

8MKRY9379030

8MKRY9379H030


FORD CLEVELAND351

(with 6” 302 Rods)(3 Ring Design)


Chev Rod


Chev Rod for SmallChamber Heads

FORD 250/4.1 FORD 250/4.1

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6


BASE PART NUMBER

DESCRIPTION

Rod Length


COMPRESSIONHEIGHT

(PIN C/L TO TOP)


* see NOTE 1

BOWL (Pocket) DEPTH







RING SET(FILE BACK)



ADDITIONAL NOTES


9400

Bowl

5.879”149.35mm

25.5mm

35.5mm

7.3

1

5cc

9.6:1 @ 78cc

460gm (1mm)105

R3365T-STDM23.17mm / .912”

M17620.5, 1.0

1.5, 1.5, 3.0

N/A

6MKRY94000.5, 1.0

N/A

9390

Bowl

5.879”149.35mm

23.1mm

35.5mm

9

1

11cc

9.8:1 @ 76cc

455gm (1mm)105

R3365T-STDM23.17mm / .912”

M1896STD, 0.5, 1.01.5, 1.5, 3.0

N/A

6MKRY9390STD, 0.5, 1.0

N/A

Also suits Stock CarRacing in New Zealand

9412

Bowl

6.27”159.33mm

21.1mm

29.7mm

6.75

1.85

8.6cc

10.0:1 @ 77cc

368gm115

R3340T-STDM23.17mm / .912”

M9124020, 030, 0401.5, 1.5, 3.0

6MKRY9412020, 030, 040

N/A

ENGINE FORD 250/4.1Using ‘200’ Rod

9413

Flat Top

6.27”159.33mm

21.1mm

29.7mm

8.6

0

0

11.2:1 @ 68.5cc

402gm115

R3340T23.17mm / .912”

M9126020, 030, 040

1.5, 3.0(2 Ring version)

N/A

6MKRY9413020, 030, 040

N/A

FORD 250/4.1Using ‘200’ Rod

Single Compression Ring

FORD EASCRA Formula

FORD EB2/EF/EL(4 litre)

Recommended only for off road use with fuel of100 RON minimum (For 9412 do not exceed

10.0:1, adjust head volume to 60cc min,)

(200 Rods may require metal removal at top to clean u/head)

7

9119

Flat Top

5.625”142.87mm

32.7

42.8mm1.686”

10

0

0

9.5:1 @61cc

487gm95

R3333T-STDM23.596mm / .927”

M9112STD, 020, 030, 040, 060

1.5, 1.5, 4.0

M9116005, 025, 035, 045, 065

8MKRY9119020, 030, 040

8MKRY9119H020, 030, 040

9115

HQ Racingwith Raised Step Crown

(L & R Versions)5.625”

142.87mm

32.7

42.8 + 2mm1.686” + 0.080”

12

0

-7.5cc

10.0:1 @57.5cc

513gm95

R3333T-STDM23.596mm / .927”

M9112STD, 020, 030, 040, 060

1.5, 1.5, 4.0

M9116005, 025, 035, 045, 065

8MKRY9115STD, 020, 030, 040, 060

8MKRY9115HSTD, 020, 030, 040, 060

HOLDEN 253HQ Racing

V8Blue / Red

HOLDEN 253HQ Racing

V8Blue / Red

9253

Flat Top (High Comp.)

5.625”142.87mm

32.7

44.8mm1.760”

12

0

0

12.8:1 @ 45.4cc

551gm95

R3333T-STDM23.596mm / .927”

M9112060

1.5, 1.5, 4.0

N/A

8MKRY9253060

N/A

Not sevicedas a Rebuild Kit

Refer to AMCA forAdvice for compliance

HOLDEN 253Speedway

(Semi-finished)


Clearance Volume = Head + Piston + Gasket + Deck Volume—DO NOT EXCEED 10.0:1

9118

Flat Top

5.25”133.35mm

32.7

42.67mm1.680”

10

0

0

10.0:1 @ 60cc

494gm84

R3334T-STDM21.996mm / .866”

M1844STD, 020, 030, 040, 060

1.5, 1.5, 4.0

M9114005, 025, 035, 045, 065

6MKRY9118030, 040, 060

6MKRY9118H030, 040, 060

9096

Bowl

5.25”133.35mm

32.7

42.67mm1.680”

9.5

0.5

2.2cc

9.8:1 @ 62.2cc

485gm84

R3334T-STDM21.996mm / .866”

M1844STD, 020, 030, 040, 060

1.5, 1.5, 4.0

M9114005, 025, 035, 045, 065

6MKRY9096030, 040, 060

6MKRY9096H030, 040, 060

HOLDEN 202HQ Racing

Blue / Black / Red

HOLDEN 202HQ Racing

Blue / Black / Red

Holden HQ’s (6 and V8 253): Experience has shown that these engines are often built at very high compression ratios (higherthan recommended by ACL) in order to develop more power. Remember that as the fuel octane value is limited with the HQformula detonation will occur if either the ignition or fuel/air ratio are not optimised. If the pistons scuff on the thrust side only itis a sure sign that there has been excessive advance (probably at low speeds, indicating that the springs in the distributor are tooweak), and/or that there has been detonation due to the compression ratio being too high for the octane value of the fuel.


8

9347S

Round BowlSingle Valve Pocket

‘L’ and ‘R’5.4”

137.16mm

19.3(Ref.)

1.100”27.94mm

6.5

1.7

9.3cc

9.1:1 @ 87cc

440gm135

N/A23.55mm / .927”

M1932005, 020, 0301.5, 1.5, 3.0

N/A

8MKRY9347S005, 020, 030

N/A

This Piston is identicalto the OEM except

it has a Round Bowl

9358S

Round Bowl

6”152.4mm

19.3(Ref.)

1.120”28.45mm

6.3

1.9

11cc

9.6:1 @ 85cc

445gm135

N/A23.55mm / .927”

M1932005, 020, 0301.5, 1.5, 3.0

N/A

8MKRY9358S005, 020, 030

N/A

Fuel Octane ofat least 98 required

*Also suits Chev 350with a 6 rod or Chev

383 with a 6” rod.

BASE PART NUMBER

DESCRIPTION

Rod Length


COMPRESSIONHEIGHT

(PIN C/L TO TOP)


* see NOTE 1

BOWL (Pocket) DEPTH







RING SET(FILE BACK)



ADDITIONAL NOTES

STROKER SERIES

FORD WINDSOR347 Stroker

HOLDEN 355Stroker*

6” RodENGINE

1—8

STROKER SERIES DESIGN DETAILS

9

Design DetailsIn order to accommodate the longer rods these pistons aremuch shorter than the original ones and as a consequencethey have part of the oil ring groove overlapping the pinbores. This means that the pins must be installed before theoil rings. Oil drainback from these solid skirt pistons is viaexternal scupper slots cast into the outer panels and thespaces above the pin holes. To prevent the lower ends of theoil ring rails from becoming jammed into the wide apertureabove the pin bore the lower rail is "tanged" with a split endwhich is to be engaged into one of the scupper slots onassembly. It has not proven necessary to incorporate a third"support" rail due to the relatively short unsupported lengthof lower rail above the pin boss. Specific assemblyinstructions apply and are included at the end of this article.

The pistons are cast from ACL’s high silicon (12.4%)aluminium alloy and subjected to two-stage heat treatmentin order to achieve maximum hardness and strengthtogether with stability.

They are all designed to be fitted with Chev/Holden diameterpins of .927" diameter, and as the intended rods will bebushed (i.e. fully floating) there are semi-circular grooves fortangless wire circlips and pre-cast removal slots on eachboss. The pinholes have longitudinal grooves for additionallubrication.

These pistons have combined barrel and ovality skirt profilesand the diameters must only be measured at the grade pointwhich is in line with the internal strengthening rib at the lowerend. It is permissible to measure the skirt diameter over thecoated skirt for setting clearances. These pistons canoperate at very low clearances due to the scuff resistance ofthe skirt coating and the complex diamond cam turnedbarrel shaped skirt profiles.

Section View of 9347S showing internal features

Skirt coatingThe special moly/graphite coating (which has beendeveloped for original equipment pistons made by ACL) isscreen printed onto the skirts after a prior phosphatingprocess which is needed to ensure good adhesion. Thecoating is cured in a three stage heat curing oven. Thecoating is highly wear and scuff resistant and reducesfriction. The clearance recommendations stamped on thetops of these pistons are based on the diameter over thecoating and the coating itself is hard enough to allow directmeasurement with a micrometer.

Piston ringsRing widths are 1.5,1.5 and 3 mm. The top rings are madefrom high strength nodular iron with a barrel lappedmolybdenum inlay, second rings are taper face scraper andoil rings are ACL Duraflex“. As earlier mentioned the lower oilring rails are tanged at one end for engagement into one ofthe two scupper slots to prevent rotation.

The pins are tapered ID alloy steel and weigh 135 grams.

Compression ratio and fuels

In keeping with the intended use of these pistons, which isgenerally for street and track use for otherwise modestlymodified engines, the compression ratios chosen will allowthe use of unleaded fuels of 95 to 98. (The latter isrecommended for anything above 9.4:1).

Horsepower rating

It is always difficult to define an upper limit for a piston. Somuch depends on the duration and intensity of any fullthrottle operation and peak RPM. However these pistons areperfectly adequate for operation at 5,000 RPM withoverspeeds to 6,000 RPM and at 300-400 BHP. Naturally forout and out circuit racing where sustained operation at 7,000and high 500’s horsepower is expected forged pistonsshould be used. The new ACL pistons are not intended forthis end of the market. However testing of these pistons inACL Technical Centre included 100 hour dynamometerrunning in a highly modified Holden 308 developing 485BHP running on Avgas. It also included durability testing ona Ford Windsor engine developing 250 kW running on PULPof 95 octane.

Ring Fitting

The stroker pistons have a large gap in the lower oil ring groove.This gap is needed because of the small compression heightand the fact that pin must be inserted before the oil rings.

In order to ensure that the ends of the lower rails (sometimesknown as segments) are fully supported they are made witha small bent tang at one end.

This tang must be assembled with its projectionDOWNWARDS and into one of the two scupper slots whichare cast into the side panel of the piston. This locks theassembly into position and prevents rotation. The ends ofthe lower rail are therefore prevented from entering thespace above the pin.

Holden Stroker piston for use with 6” Rods—Note: Rods notNecessarily ‘over the counter’ for this specialist part number.

10 Continued on page 13

ACL Performance pistons arefitted with high strength alloy steeltapered bore pins. These save upto 20 grams compared to thestandard pins.

These are now available separately.This enables engine builders usingthe standard pistons, which haveparallel bore pins, to replace theseand obtain a weight saving.

Part numbers and diameters areshown in the “Applications andData Pages”.

Fit: The tapered pins are made tothe same diameter and toleranceas the parallel pins so they can befitted to relevant ACL pistons withno clearance adjustment. Usersmust take responsibility for fittedclearance should these pins beused in any piston other than theACL pistons listed in the tabulationabove. In moderate performance

applications clearance wouldnormally be in the range 0.008 mmto 0.016 mm (0.0003" to 0.0006").Clearance can be greater than thisat the possible detriment to noisein higher output engines.

Lightening for balancingpurposes

It is permissible to grind smallamounts of metal from the ends ofthe pins but if this is deemednecessary the amount removedshould be minimised and extremecare must be taken to avoidexcessive heat during the grindingoperation. The pin must not bediscoloured at any time as thismay affect the heat treatment.

NB: These are the only separatepins supplied by ACL. All otherpins are serviced as part of apiston assembly.

ADDITIONAL FILE BACK RING SETS

This list contains file back ring setswhich are NOT listed in thetabulation of this bulletin. For fileback sets to suit ACL Performancepistons please refer to the relevantlisting in the tabulation.

Please note that file back setsgenerally have a top ring which ismade with zero gap if fitted to thestandard or standard oversizecylinder bore. (It does NOT meanthat the set is intended for anoversize bore)!

That means the gap will have to befiled to the size required by theengine builder. Most, but not all, ofthe sets have standard sizesecond rings because the gaps onsecond rings have far lessinfluence on blowby and should inany case be (if anything) a littlelarger than the top ring gap. Thepart number designation for ACLfile back sets is to add"005,025,035 etc." to the ring setpart number.

Application Set number Grooves

V8 Holden/Ford/Chev etc. 4" bore M 9098-005/025/035/045/065 5/64", 5/64", 3/16"

V8 Holden/Ford/Chev etc. 4" bore M 9103-005/035 1/16", 1/16", 3/16"

Formula Ford 3.189" bore M 9099-005 1/16", 2 mm, 4 mm

Holden 3800 V6 Formula Holden M 9100-005 1.5, 1.5, 3

Holden 3800 V6 Formula Holden M 9095-005 1.5, 1.5, 4

TAPERED BORE PINS Ford 377 stroker using Chev rod: Bearingsfor narrow rods

This conversion is popular and is based on theCleveland crankshaft being stroked by 0.200"and fitted with a 5.7" Chev rod. The crankshaftcan be widened to suit but most engine buildersseem to prefer the rod to be reduced in width.This preserves the crankshaft's originalstrength. To help with this approach ACL has aspecial bearing set, 8B7110 available instandard and 010" undersize. These bearingsare already at the correct width for the narrowedrods and the oil hole is in the right place.

NOTE: The crankshaft counterweights will needto be reduced in diameter to clear the pistons.

Balance (V8 Engines)

V8 crankshafts need to be balanced with bobweights attached to the journals representingthe weight of the pistons and rods according toa formula depending on whether a neutral orover or under balanced situation is required.The weight saving (which varies from 35 to 90grams depending upon the application) willrequire that the crankshafts to be used withthese new ACL pistons will have to be balancedtaking into account the new weights.

RINGS

The top rings supplied with most piston kits andrebuild kits have pre-gapped molybdenuminlaid high strength iron top rings. File back setsare available for some of the range.

The second rings are cast iron reverse torsionaltaper face scraper type, unique to ACL.

The oil rings are ACL Duraflex® which in mostcases (i.e. all lightweight V8's and HQ's) arelower in load to reduce friction. The Duraflex®expanders cannot be assembled overlapped

Intended use

ACL’s performance pistons enable many specialistengine builders and private owners to build verydurable performance engines for a variety of uses.Depending on the application and the degree oftune, compliance with relevant emissions limitsshould still be achieved in which case the pistonsare perfectly suitable for street use (especially inthe case of the pre-leaded fuel engines). ACLcannot take responsibility for any piston used in amodified engine with regards to compliance withemissions or other regulatory requirements.

Also what cannot be anticipated is the wholerange of performance applications to whichthese pistons are to be subjected. Users maychoose from a huge range of valve timingoptions, alternative head types, compressionratios, stages of tune and RPM limits. For thatreason ACL can only fully warrant Performancepiston assemblies for use in street applications

ADDITIONAL NOTES AND ENGINE BUILDING ADVICE

9490


5.625”142.87mm

34.2mm

43.6mm1.710”

9.4

0

0

9.3:1 @ 78cc

565gm120

R3326T-STDM23.55mm / 0.927”

M9106STD, 020,030, 040, 060

1.5, 1.5, 4.0

M9110005, 025, 035, 045, 065

8MKRY9490020, 030, 040, 060

8MKRY9490H020, 030, 040, 060

9570

‘D’ Bowlhigh compression

Left & Right versions5.625”

142.87mm

27.6mm

38.31.508”

7.7

3

17cc

9.5:1 @ 85cc

475gm120

R3326T-STDM23.55mm / 0.927”

M9106STD, 020,030, 040, 060

1.5, 1.5, 4.0

M9110005, 025, 035, 045, 065

8MKRY9570STD, 020, 030, 040, 060

8MKRY9570HStd, 020, 030, 040, 060

Not Suitablefor 91 unleaded

(98 Recommended)

9571

Round Bowlreduced compression

5.625”142.87mm

27.6mm

38.3mm1.508”

5.7

5

24cc

8.8:1 @ 91cc

470gm (020)120

R3326T-STDM23.55mm / 0.927”

M9106STD, 020,030, 040, 060

1.5, 1.5, 4.0

M9110005, 025, 035, 045, 065

8MKRY9571STD, 020, 030, 040, 060

8MKRY9571HStd, 020, 030, 040, 060

Suitable for91 Unleaded

9500


5.625”142.87mm

34.2mm

43mm1.690”

8.8

0

0

9.3:1 @ 76cc

555gm128

R3326T-STDM23.55mm / 0.927”

M9106STD, 020,030, 040, 060

1.5, 1.5, 4.0

M9110005, 025, 035, 045, 065

8MKRY9500STD, 020, 030, 040, 060

8MKRY9500HStd, 020, 030, 040, 060,

2

BASE PART NUMBER

DESCRIPTION

Rod Length


COMPRESSIONHEIGHT

(PIN C/L TO TOP)


* see NOTE 1

BOWL (Pocket) DEPTH


COMPRESSION RATIO AT TOTAL


WEIGHT BARE (STD)PIN WEIGHT (NOM.)


RING SET(PRE-GAPPED)

WIDTH (mm)

RING SET(FILE BACK)



ADDITIONAL NOTES



ENGINEHOLDEN 308

Leaded Petrolto 1985

HOLDEN 4.9Unleaded Petrol

from 1987

HOLDEN Stroker to355 with Holden Rod

and 3.480” Crank—forAvgas/Super

HOLDEN 5.7 HSV or Stroker to 355 withHolden Rod and 3.480”

Crank—Super/ULPHolden202. Red RAC9096DBB1 6MKRY9096-030 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTR2.2cc Bowl RAC9096EBB1 6MKRY9096-040 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTR

RAC9096FBB1 6MKRY9096-060 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTR

Holden202. Red (Flat Top) RAC9118DBB1 6MKRY9118-030 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTR

RAC9118EBB1 6MKRY9118-040 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTRRAC9118FBB1 6MKRY9118-060 6BHP2380-010 7MHP2398-010 4C5116-STD FG392GTR AG390GTR

Holden202. Blue, Black RAC9096DBB2 6MKRY9096-030 6BHP2380-010 7MHP2398-010 4C5116-STD FH110GTR BH110GTR

RAC9096EBB2 6MKRY9096-040 6BHP2380-010 7MHP2398-010 4C5116-STD FH110GTR BH110GTRRAC9096FBB2 6MKRY9096-060 6BHP2380-010 7MHP2398-010 4C5116-STD FH110GTR BH110GTR

Holden3.8 V6 High Comp RAC9380CBB1 6MKRY9380-020 6B2360-010 4M2362-010 4C5106-STD GR721GTR BR720GTRVN (5/88-11/90) RAC9380EBB1 6MKRY9380-040 6B2360-010 4M2362-010 4C5106-STD GR721GTR BR720GTR23.6cc Bowl

Holden3.8 V6 High Comp RAC9380CBB2 6MKRY9380-020 6B2306-010 4M2302-010 4C5106-STD GW940GTR BW940GTRVN, VP (11/90-1/94) RAC9380EBB2 6MKRY9380-040 6B2306-010 4M2302-010 4C5106-STD GW940GTR BW940GTR23.6cc Bowl

Holden3.8 V6 High Comp RAC9380CBB3 6MKRY9380-020 6B2306-010 4M2309-010 4C5106-STD GW940GTR BW940GTRVR 23.6cc Bowl RAC9380EBB3 6MKRY9380-040 6B2306-010 4M2309-010 4C5106-STD GW940GTR BW940GTR









Holden355. Red RAC9355DAA1 8MKRY9355-030 8B663H-STD 5MHP2357-STD 5C5146C-STD FX142GTR AX140GTR(Stroker Round Bowlusing Chev conrods)

Holden4.9L. (Flat Top) RAC9490DBB1 8MKRY9490-030 8BHP2356-010 5MHP2357-010 5C5146C-STD GS150GTR BS150GTR

RAC9490EBB1 8MKRY9490-040 8BHP2356-010 5MHP2357-010 5C5146C-STD GS150GTR BS150GTR

Holden5.7L. 17cc “D” Bowl RAC9570DBB1 8MKRY9570-030 8BHP2356-010 5MHP2357-010 5C5146C-STD GS150GTR BS150GTR

Holden5.7L 23.8cc Bowl RAC9571CBB1 8MKRY9571-020 8BHP2356-010 5MHP2357-010 5C5146C-STD GS150GTR BS150GTR

RAC9571DBB1 8MKRY9571-030 8BHP2356-010 5MHP2357-010 5C5146C-STD GS150GTR BS150GTR





R A C E S E R I E S A P P L I C A T I O N A N D C O M P O N E N T L I S T I N G





Chevrolet350. (Flat Top with RAC9350DBB1 8MKRY9350-030 8B663H-010 5M909H-010 5C3349C-STD FP400GTR AF830GTRSingle Valve Recess) RAC9350EBB1 8MKRY9350-040 8B663H-010 5M909H-010 5C3349C-STD FP400GTR AF830GTR

Chevrolet350. (20cc “D” Bowl) RAC9352DBB1 8MKRY9352-030 8B663H-010 5M909H-010 5C3349C-STD FP400GTR AF830GTR

Chevrolet350. (Flat Crown RAC9353DBB1 8MKRY9353-030 8B663H-010 5M909H-010 5C3349C-STD FP400GTR AF830GTRNo Valve PocketsSemi-finished)

Ford302 Windsor RAC9302SDBB1 8MKRY9302S-030 8B634H-010 5M590H-010 5C5616C-STD FG971GTR BD870GTR(Flat Top) RAC9302SEBB1 8MKRY9302S-040 8B634H-010 5M590H-010 5C5616C-STD (Pre EFI) BD870GTR

Ford302, 351 Cleveland RAC9351DBB1 8MKRY9351-030 8B927H-010 5M91470-010 5C5696-STD GC230GTR AW980GTR(Flat Crown with RAC9351EBB1 8MKRY9351-040 8B927H-010 5M91470-010 5C5696-STD GC230GTR AW980GTRValve Pockets)

Ford351 Cleveland RAC9356CBB1 8MKRY9356-020 8B927H-010 5M91470-010 5C5696-STD GC230GTR AW980GTR(Flat Top Using 6” RAC9356DBB1 8MKRY9356-030 8B927H-010 5M91470-010 5C5696-STD GC230GTR AW980GTR302 conrods)* *(Supercedes RAC 9357)

Ford377 Cleveland RAC9377DBB1 8MKRY9377-030 8B7110-010 5M91470-010 5C5696-STD GC230GTR AW980GTR(Flat Top using (Duraglide)Stroker Chev conrods)

Ford377 Cleveland RAC9378DBB1 8MKRY9378-030 8B7110-010 5M91470-010 5C5696-STD GC230GTR AW980GTR(10cc Bowl Version (Duraglide)using Stroker Chevconrods)

Ford 3.9 EA, EB RAC9390CBB1 6MKRY9390-0.50 6BHP2150-010 7MHP2158-010 GR520/1GTR BR520GTR

RAC9390EBB1 6MKRY9390-1.00 6BHP2150-010 7MHP2158-010 GR520/1GTR BR520GTR

Ford 4.0 EB2, ED, EF, EL RAC9400CBB1 6MKRY9400-0.50 6BHP2150-010 7MHP2158-010 GR522GTR BR520GTR

RAC9400EBB1 6MKRY9400-1.00 6BHP2150-010 7MHP2158-010 GR522GTR BR520GTR

Ford4.1/250 RAC9410CBB1 6MKRY9410-020 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR(Flat Top) RAC9410DBB1 6MKRY9410-030 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR


Ford4.1/250 RAC9411CBB1 6MKRY9411-020 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR(8cc Bowl Version) RAC9411DBB1 6MKRY9411-030 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR


Ford4.1/250 RAC9412CBB1 6MKRY9412-020 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR(Using 200 conrod RAC9412DBB1 6MKRY9412-030 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR8.6cc Bowl) RAC9412EBB1 6MKRY9412-040 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR

Ford4.1/250 RAC9413CBB1 6MKRY9413-020 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR(Using 200 conrod, RAC9413DBB1 6MKRY9413-030 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTRFlat Top 2 Ring Piston) RAC9413EBB1 6MKRY9413-040 6BHP2150-010 7MHP2158-010 4C5826-STD GH100GTR BH100GTR

(NOTE—NOT ALL PISTONS IN THIS SERIES AVAILABLE IN REBUILD KITS)

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FEATURES• Lightweight design for improved engine

acceleration and lower bearing loads

• 30% Stronger than original pistons

• High silicon aluminium for high strength and lowexpansion

• All have pressure balancing grooves

• Lightweight tapered pins

• High strength moly filled or nitrided steel top rings

• Long rod versions reduce weight further

• Stroker versions for greater capacity

• Suitable for Street, moderate track, sprint and marine

• Low friction rings

• In most cases eliminate need for forgings

Automotive Components Limited MAHLE-ACL ACL Bearing Company ACL Gasket CompanyLevel 8, 390 St Kilda Road Piston Products 253-293 George Town Road Cnr Acacia & Bunya StreetsMelbourne 2-8 Oxford Road Rocherlea Eagle FarmVictoria 3004 Laverton North Tasmania 7248 Queensland 4009Phone: (03) 9285 4000 Victoria 3026 Phone: (03) 6324 4600 Phone: (07) 3365 0700Fax: (03) 9866 4300 Phone: 1300 363 356 Fax: (03) 6326 6666 Fax: (07) 3268 6662ABN: 51 006 542 785 *Orders Only

AUGUST 2003

“AUSTRALIAN ENGINEERING EXCELLENCE”

TSD3Technical Hotline: 1800 033 113 (Piston and Ring only) http:/www.acl.com.au

A.C.N. 006 542 785

AutomotiveComponentsLimited

6. The pins must be fitted to heated rods. The rod eyemust be in good condition and must never be overheated,either generally, or in any one spot. Use a or heavy oil ormoly based grease to lubricate the pin bore at the time ofassembly. Use heat crayons to ensure rod eyes are notoverheated. Always check for freedom of movement afterthe assembly has cooled down. Always relubricate thepin with heavy oil or a moly and oil mixture to preventseizure on start up. It takes a long time for oil to reach thispoint even if the engine is primed first, (as it should be).

7. The rings and skirts should be lubricated with lightengine oil prior to assembly and ACL bolt protectorsused to prevent the rod bolts damaging the crankshaft.

8. Honing for performance engines: Best results will beachieved if a deck plate is used to neutralise the effectsof head bolt tension on bore distortion. Obtain a smoothsurface finish by honing to size with a 210 to 320 gritstone and finally finishing with 400 grit or better (flexiblehoning or stone) to achieve a plateau. For further detailsrefer to ACL Bore Finishing Guide. Clean bores with hotsoapy water and nylon brush and swab with clean engineoil. Do not use petrol or kerosene, neither will clean thebores properly. Finally, always check cleanliness with aclean white cloth which must not come out grey!

9. Modifying pistons: All of the versions mentioned here(except 9353) are finished pistons and should need nofurther modification. However should any minor crownmilling or machining be needed to achieve specificcompression heights and compression ratio then caremust be taken to avoid very thin sections between thetop of the crown and the underhead. A minimumthickness at any one point of 6 mm should be retainedand general head thickness 7 mm. Top land height (fromthe top ring to the top of the piston (or valve cut out inthe case of the Ford pistons) should never be less than 4mm). Care must be exercised when gripping the pistonto avoid damage and skirt distortion. A mandrelmachined to support the piston on its spigot register (atthe open end) plus pin pull back should be used forcrown face turning and the piston clamped on its crownfor milling. If balancing is required metal must NOT beremoved from below the pin bosses.

10 Valve Clearance: When enlarged valves or higher liftcamshafts are used the valve to piston clearence MUST bechecked using plasticine in a trial build. In any case valveto piston clearence may still need adjustment for some ofthe non-standard applications listed in this bulletin.

11 Tuning your engine: Increasing compression ratio of anyengine will require changes to the tuning of the engine, inparticular the ignition, air fuel ratio and spark plugs.There are many specialist books on this subject. Withincreased compression ratio it is inevitable that while theinitial advance setting may be the same, the advancecurve will need to be adjusted to reduce the amount ofmechanical (and vacuum if any) advance. Air fuel ratio isalso important and with any increase in output it is

essential that leaning out at high RPM is avoided. Soslightly richer mixtures may be needed. Colder heatrange spark plugs may also needed depending upon thedegree of modifications and anticipated usage. Adviceshould be sought from spark plug manufacturers.

12. Finally it goes without saying that the accessoriessuch as distributor, coil and leads, all fuel systemcomponents, water pump and cooling system mustbe in excellent condition in any performanceapplication. Depending upon the extent ofmodifications the cooling system may well requireupgrading since the output from the modified enginemay require more cooling than was available from thestandard components.

Where to measure clearance

Measure clearance in line with internal rib for any pistonmarked "BOT" or "RIB" also known as "Band", or “Mid” ifspecified. Never measure across the tails of a piston.

Measure piston diameter in line with internal rib.

Warranty: ACL Performance and RACE brand pistonassemblies.

ACL Performance range and "RACE" brand pistonassemblies with "9000" series part numbers are designed toenable specialist engine builders to obtain moderateincreases in compression ratio and engine speeds forotherwise standard engines. These pistons are not designedfor use in forced induction (i.e. supercharged orturbocharged) engines or for use with fuels other thanleaded or unleaded pump petrol and 100 octane aviationgasoline. ACL does not provide any implied or expresswarranty on products used in engines over whose design ithas no knowledge or control and users must acceptresponsibility for use in non standard applications includingany use in engines used in competition or where exhaustemissions regulations apply. ACL reserves the right to makeproduct changes without notice and without incurring anyliability for similar products previously manufactured.

Nigel TaitChief EngineerAutomotive Components Limited

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Need other Information?(1) Dial (03) 9866 4349 for information in Techfax or on the internet, www.acl.com.au

(2) For piston and ring Technical enquiries telephone 1800 033 113(3) For gasket Technical enquiries telephone 1800 777 149

(4) For bearing enquiries (03) 6324 4600

The information in this publication has been compiled from the most reliable sources available. Although all care has been taken in preparing and researching thisinformation, we cannot be responsible for any errors that may occur. All information in this publication is copyright and reproduction in whole or part is not permittedwithout the written consent of Automotive Components Limited A.C.N. 006 542 785

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PISTONS AND ENGINE REBUILD KITS

Chevrolet – 350, 383

Ford – 250, EA, EB-EL 4 Litre

Ford – Cleveland 302/351, 377

Ford – Cleveland Long Rod 351

Ford – Windsor 289, 302

Ford – Windsor Stroker 347

Holden 202, 253, 304, 308, 355, V6

where the engine is close to its original specification but isused for mild extensions of the originally envisaged power,torque and speed. They are NOT intended to displace forgedpistons in out and out racing applications where output wellin excess of 100 BHP per litre is expected. See also warrantynotes elsewhere in this bulletin.

Supercharging or turbocharging

Forced induction engines generally require significantreduction to the compression ratio to prevent severedetonation. ACL's Performance range pistons have higher compression ratio than standard. Consequentlythese pistons are not intended to be used withsuperchargers or turbochargers.

Avoid Detonation!

As with any piston, performance or otherwise, detonation isextremely harmful and will inevitably lead to failure. Caremust be taken to avoid this by careful tuning and correctselection of petrol octane relative to the compression ratio ofthe special engine, spark plug heat range and fuel andignition settings. Also remember that any performanceengine will develop more power than the original andtherefore more heat rejection to the cooling system. Thecooling system must therefore be reviewed to make sure ithas adequate capacity to cope with the higher loading.

Assembly and installation hints

1. Clearance: ACL's high silicon alloy enables lowclearances to be run and this improves ring sealing dueto better control over the piston's movement in the bore.The clearance marked on the top of each piston is therecommended minimum only and extra clearance mustbe given for engines where considerably more powerthan the standard is expected and when continuous highspeed operation is needed. Also if the compression ratiois increased further than by the difference of the pistonover the standard piston (e.g. by block or head milling, oruse of small combustion chamber heads), then an extra0.001" or so will be needed. For marine use allow anextra 0.001" then a little more depending on the severityof use or degree of other modifications.

2. Check squish height. This is the distance from the topsurface of the piston to the corresponding flat part of thehead's surface. Adjust block height if necessary to givearound 0.040" which will mean in most cases the pistonbeing at or near the deck face at TDC. Too little squishheight could result in the piston touching at high speed.Too much will lessen the squish effect and could lowerthe maximum compression ratio that can be used for thegiven fuel before detonation occurs.

Measure the deck height at TDC with a depthmicrometer.

3. Compression ratio: The tabulation shows the nominalcompression ratios which will be achieved if the newpistons are used in conjunction with standard bore sizesand standard blocks and heads.

As earlier mentioned the increases over standard areapproximately 1 ratio. Any further increases due to heador block machining are at the risk and responsibility ofthe user bearing in mind that the pistons are most likelyto be used on pump petrol (or possibly 100 octaneAvgas). DO NOT EXCEED 10.0:1. No piston is immune tothe effects of detonation.

Measuring cylinder head bowl volume with a burette.

4. Check ring gaps and adjust file back top rings ifsupplied. Do not strive for very small gaps especially forhigh compression ratios or continuous high speed. It isbetter to have a little too much than to run the risk ofbutting (which will seize the whole piston). A gap of lessthan 0.016" should seldom be necessary and theadvantage gained in having smaller gaps is minimal. Formost performance 4” Applications an initial gap of 0.020’will be an ideal starting point. When filing gaps it is bestto hold a small sharp single cut file in the vice and holdthe ring in your hands when filing. File only one side ofthe gap using the other side as a guide to keep thefinished gap square. Deburr but do not file any chamferon the outer edge, this will increase blowby at this point.The second rings in file back sets are not file back type.For performance engines second rings should have alittle more gap than the top rings, certainly never less ortop ring flutter may be induced at high RPM.

5. Assemble all rings according to the instructionssupplied and check back clearance, and that the secondrings are fitted with the dots upwards. Mixing brands ofrings and pistons is not recommended because thetolerances on side clearance and back clearance maynot be compatible.

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