HOW TO

"WILD WILLIE" BORSCH

DICK LAN DY'S PRO-STOCK 1970 DODGE CHALLENGER

E V E R Y B O D Y ' S AUTOMOTIVE M A G A Z I N E WHAT'S NEW FOR INDY? MAY 1970 RACING INJECTION

SYSTEM FOR VWs

WA X •

i

We asked Buick if they ever played around with trick engines. They said they could show us a couple. Just looking kept us busy for near­ly two days

by Sieve Kelly

/Engine sequence: from left to right) Air box uith tube runner*

is a development too foe calculating best intake

manifold *hape & runner length. Here, it i$ on

Stage II ux#khor*e VS. Next up is the 425 turbo-

charged vertical'vati* engine that almost became a protluetion

option. Third VS shotvn is the Indy experiment, though thin one has Weber*

on a cross-ram. Hilborn ua* used at the "SCO."' Stagneto and uater pump driving front cover

ua* uorked up by Mickey Thompson. lAite-series big' block uith Webert and header* as a development piece

for Stage I parts. (Opposite right) Buick's Nelson Hum hold* model of permanent cast mold aluminum block

that ted to dei<etopment of current bijt-dt*$>tactment east iron block.

photography: Ron De R« em acker (GM Photographic)

3 2 H0r*0O*MY19;0

• t s reasonable to assume that Ku i ck I remained a'.ool from high-perform -| nncc car-bui ld ing act iv i ty almost in <ii r«« t i l l 114111 iv* of M ' IJ IM l l n r i . i ; th i l l W . I H

nhviously going on around (hem. Tha t assumption inn;ht bo fostered hy tin* fact that Huirk never sot into the game o n a first-name Ixisi*. In the late *30* and ear ly '*M>*. there wore dua l -earbureted xt raight eight Eiuick*. being huilt that were <-rju:(| to imr%t anyth ing of that era. Butck brought out their first ovcrhcad-valvc V 8 in 1 fX5^; one year Inter, the 322-nib icdncher showed up with s o t i i i high-suds .netton anil mode the (lien now Duick Cen tury a hot i tem. In 1955, they Mild enough €•41 r- io Uo>nu< th i rd i n the market , and scored two N A S C A R wins, wh ich tied Chevrolet for shx-k ear wins in that c i rcui t . A price figure n l w w their com-petitorV hoi machines d idnH keep hot r v i r l d i T * I - l i v i n g Tsaiirk*. :»rwl h:vl < l l i * r

ft tarter hren on the right side instead of the l i f t , ttayhc there would have \H VTI more engine swn|* using th.it Old vertical-valve H u k k . Then* were a number of drawbacks i n that t i n t design: Pee r ing box interference be* twven starter and steering on ear ly-model car swaps: l imi ted valve sixe due to It4 :td design; and a not-tno-a lnnd i i n t supply cif >peod equipment.

Kng inc development at the F l i n t . M i ch i gan . o|w>rntion has been quite na­t ive i n spite of a Lick of Bu i cks on race tracks. Most of the engine experi­mentat ion Itfls a hot rod flavor, J L S W C

discovered when their engineering dc-u a r t m u t rr.innged to pa l l together a display of vnrious <le\elopmcnt project*.

Iv is i ly (lit- nvo.«t interesting i tccom-pl ishmrnt i< the Indianapol is |>nwer-l i lant, jissemhted i n conjunction wi th M i ckey Thompson f<ir the IJM12 " M O . " Dan <i«rney drove Mickey** then-con-trover>ial renr-cngined Champ ionsh ip car. which was g lowered by a n a lumi ­n u m l iu iok (Jurney qualif ied in i*ighth *fxit, hut a dr ive- l ine fa i lure after *J3 lairt put h i m out and the car p)ai*e<l in "XMh s|Kit. I'nwer tr . in- iuivt ion was

a somewhat homegrown adapta­tion of ; i M < K I I ' I A Kearl»>\ fitted into a t ramax l c case. Thompson approached Httick w i th h is engine idea, and the hulk of its development wa* €loi»e i n F l in t . H u n k didn ' t go far as to get into the racing end. as that was Mickey ' s job. T h e i r development re­mained W i t h i n t in * realm of i xp<'runi«n-t.ition w i th an eye to the future. I5»H-placement was increased from the slock 2 l a inches to 2SG cubic inches. which fit tlie sh-ck-hloek rules. Bore w m l from 3.50 inches to 3.G25 inches, which fit the stock-block rules. l ioro went fmm 3.50 inches to 3.W> inrhes. and stroke was lengtliened from 2.80 inches to 3.100 inches. Interestingly enough, a MtrokiNl cant i n m prrKluction crank wa<» rev\v>rked an<l us**<l in the ongiru*. dui* I n l;i<k of development tune for a forges I crank. Valve *i/.c w.is set at l ^J - i n ch intake and l 7 ie.-inch ex-

(Uoniinuerf ort jotlotving p*W)

MAY 3970 • HOT ROD 3 3

BUICK'S BACK ROOM"

huust. Heads wore cast w i th largor- than-stock ports and then opened u|> fur ther on an automat ic m i l l i n g machine . C o m ­bust ion chaml )cr conf igurat ion d idn ' t get changed at a l l , hut Thorn |»son made up a set of domed. forged a l u m i n u m pistons wh ich brought compression up to 1-1.0:1, needed for the a lcohol fuel. A semi -Mock steel-beaded head gasket was ma<le up . wh i ch differed from a pro­duct ion gasket by having a wider cha in IK* r toad w i th propert ies s i m i l a r to an " O " ring, and it was also a few thousandths thicker . D r y sleeve c y l i n ­der l iners wvrc flanged at the top to a i d cotnhut l ion seal ing. D i rec t -por t l l i l h o r n injectors ran in the race, but

crossover ram tubes w i th Weber * were tr ied d u r i n g pract ice. T h e injectof f offered less trouble at that t ime.

Ne l son Kunat. B u i c k ' s Ass is tant Staff Kng inoor . was " u l l o w v d " to head the Indy project. W h e n he was caught up w i t h norma l duties, M i c k e y and N e l ­son worked closely, and K u n x was able to prescribe changes to make the a lu ­m i n u m hlock more sui ted to this use. T o t a l t ime spent f rom start to f inish « M on l y three months, w h i c h com¬pares w i th the b l ink nf a n eye on this k ind of endeavor. T h e block was re in­forced i n the bu lkhead area and had

sol id sections from the center sk i r t area to the m a i n sect ion. Stock blocks were cored out here for a weight-sav­ing. T h o m p s o n made a dry -sump sys­tem, and a lso worked out the front cover wh i ch housed the o i l pump a n d magneto. T h e camshaf t is referred to as a n M l profile, and rol ler l i f ters ca­pable of a n easy 7cXK> rpn i were bui l t by Crower . Hods were -13-10 .steel, hearings were M o r a i n e 400 w i t h grooves i n the lower half , and bearing caps were in ­creased in height and fitted w i th 12-point cap screws. T o h a n d l e the i n ­creased compress ion, a s i x th cy l inder head bolt locat ion wo* added. Power reached 370 horsepower at 7200 r pm on alcohol a n d had a very flat curve between 4x100 and 7200 rpm. G u r n c y bettered M 7 m p h to qua l i f y , wh ich was less than three mi les a n hour f rom Pa r -ne l l i Jones 's po le -w inn ing speed.

Abou t 15 of these exper imenta l en­gines were bui l t , and the Thompson -l n d y engine later wound up i n a rear-cng incd sports c a r dr i ven by Rodger W a r d i n the lat ter part of *G2. I*anco Hcvcnt low , one*t ime smash hit of the .sports ear c i r cu i t , also conducted " f ie ld t es t ing " of the smal l -b lock B u i c k . Rev-ent low cu r r i ed o n n pret ty fu l l -b lown project, w i t h a n engine near ly ident i ­cal to the Indy motor, except that i t u-ed W< I M T - and ran ..n *.; isoline. B y the t ime Hevent low got his engine sort­ed out . the Webe r induc t i on had been

smoothed out. H i s i>owx*r readings were about 10% lowor than o n the T h o m p ­son engine, most of w l i i ch was due to us ing p u m p gasoline Instead of a l ky .

The a luminum-b lock B u i c k was the Kxsis for Jack B r a Imam's Kcpco -Brab -ham V 8 wh ich helped h i m w in the W o r l d D r i v e r s Champ ionsh ip in I960. and B r u c e M c L a r e n used one in his ear ly G r o u p Seven car. T h e a l u m i n u m block passed into B u i c k history after 10G3, hut it and the various exper i ­ments proved valuable i n showing how to construct a l ightweight cast i n i n VS. A nurntor of 250 cubic- inch a l u m i n u m designs were made, and these were i n ­stal led in S k y l a r k couj>es am i used for demoast rat ion vehicles ami test beds in a l l parts of the country . A J55» CUbic-iuch. fu l l -permai ient- ino ld block, w i th l iners cast i n place and open-top water jacket*, was fashioned and uses! solely as a development tool l eading to the current l ightweight cast i ron blocks (-J0O. 430 rod 455). T h e 455-cubic-ineh cast i ron engine now in use weighs 616 l iounds total , less a few mino r pieces of hardware but inc lud ing a l l operat­ing components. Comparab l e weights w i th in the C M fami ly are : Chevrolet 454, 719 ]>ounds: Pontine 45ik 63o |x>unds: OhUmobi l o -1.V>. l i V . pounds.

A very ear l y performance-engine de­velopment was conducted way K i c k i n U»5o. when a stock block uas brought out to 3.1-1 inches a n d eventual ly fitted to a K u r t i s K ra f t s|tnrts car s|s>nsored by B i l l M u r p h y Buiek in Cu l v e r C i t y . Ca l i f o rn i a . S u m H a n k s was- promot ing the vehicle and M a x Bulcho\\>ky was the rh i e f mechanic . If the name " O f Y e l l e r " nutans any th ing to y ou . then you know about the talented Bulchow-sky. H i s homemade sports car just aliout wreaked total h:unc upon U M

In st of the wor ld 's sports cars i n the mid-fift ies. M a x also t r ied bu i ld ing and sel l i ng a B u i ekeng i nod *jx>rt* ca r K I S I S : ) nn an Kng l i sb madum* u l l u l t in-Durc t t i . These were def initely a hand­ful in a l l respects, a m i the program was s im i l a r to the She lby A C * C o b r a proj ­ect. M a y to it was too ear ly for such a p lan to work, this one center ing around the late l*J30s. A n y w a y , it d idn ' t .

T h e vort ical-valve 35-1 V 8 engine i n this project rccoivi*d n H i l b o r n injec­t ion, n very unusua l induct ion system for road racers at that time. A good deal of head p o l i n g was done, a m i that 's something these engines respon­ded to by showing good power in­crease1** T h e camshaft was for use wi th mechanica l l i f ters, and Ixvausc a l l records a t ou t it are now many years lost, a l l that It known about the c a m is that it had an except ional ly high lift and worked bevd at fiOOO rp™. Va l v e sixe o n the intake was 1.675 inches, whi l e exhaust measured 1.50 inches, and both were ident ica l to valves even-

TOP — Kum and author inspect one of iuo remaining cylinder head* from OffC engine. jVo/e canted 4o7rv*s and rather lotr dome of near-heminpherical chamber. Complete OffC engine (above) used chain drive and hvdrauticaltv ad-

*T ar

justed i*$lve clearance, lltock and most other piece* were stock. fiEf.OW — 77»r« injectvtf 354-inch VS dates back to mid-'50s and uxtund up powering a West Coast-campaigned Kurtis road racer.

3A MOT ROD • N4AY 1970

FAX LEFT - Sto*e If component* a**cmbted here rrpre*ent much development time and eifxm*e. So pinna have been mode foe pradti. /fOn. LEFT - Denm Manner help* illustrate port differ* ences in Stage II head*. On fur left is Stage II exhaust, far right it intake. Stock .%/rrr/**tf are in center of display.

tun l l y u<cd when the 401 V 8 was intro­duced i n A forced steel c rnnk was used, as were forged rods a n d pinions. Power ou tpu t was better t h a n one horsepower |>er cub i c inch: 376 Itorse-power at 6600 r p m o n gaso l ine : '111 horsepower at WOO r p m us ing n lcn l i o l .

Before it was rep laced in HXi7. the o r i g i n a l 322- inch V * grew to 125 cub i c i ruhe * . T h e first 425 was bui l t for the '03 cars , a n d an 19G1 * turbocharg ing exper iment waa conduc t ed on a 425. w i t h the resultant torque ou tput be ing an u n r e a l 7raX Ihsv-ft. at a 2K00-rp in speed. T h i s was o n a n eng ine <lyno, a n d m i n i m u m hack pressure by way of unres t r i c t ed exhaust was par t of the test. Ho r s epowe r w ; i * also at a very t ime l y po in t for m id - range use; 800 at oflOO r p m . B o t h horse|>ower an<l torque wvre we l l suiirst for use w i t h a n auto­ma t i c t r j a w n i s s i o a . a n d at that t ime B u i c k was us ing the tw*>-*pcocl D y n n -How. T h e turhoch ar,:. r was a T h o m p ­son P r o d u c t * uni t w i t h a m v * l e r ing *i/e larg i r than used on today \ Meye r -I)rak<* r . u i i i ; : i - n x i m - * It was f itted to a water -coo led in l e t , a n d carburet ion v..is f rom .i pa i r of sub- draft curb* us ing progress ive of>cning throt t les , Sho r t - l eng th e x h a u s t man i f o lds , de­signed to t . i U M - a m i n i m u m temps'ra-ture rise time, fed in to the turbo , a n d there was no waste gate used . T o t a l pressure increase was a lmost equal to increas ing engine speed , a n d the s t a l l a c t i on of the au tomat i c a l l owed fires-su r e r ise so that there was no notice­ab le lag i n power u p o n takeolT. T h e s l ight l ag between gear c h a n g i n g a lso kept the tu rbo p u m p i n g so that power was a v . i dah l c when the t ransmiss ion f ina l l y r eached the next singe. D u r a b i l ­ity lest f o n bo th four-»|»ecd a n d auto­mat i c ca rs p roved that the four-speed's in.ire d i rest c o u p l i n g made for a s l ight l ag I v f o rc the tu rbo ac t i on made its way to the eng ine T h a t is. unless the throt t le was j abbed a few t imes before i n i t i a l acce lerat ion , a n d then the Jolt was someth ing fierce. T h i s ac t ion wou ld qu i t e of ten cause a negat ive re­

liction on the drive train. The auto­matic absorbed the loading better and caused fews-r drive line problems.

T h e turhocharged engine was has* ically stock cacept for high-tempera¬ture material, chrome stemmed valves and a cam timing change. It had a very "frit" torque Isiud utd came close to production for optional use in the 1<>G6 Wildcat serins. Production coat and lack of total justification had much to do with production notices being canceled. T h e drive train engineers pratably heaved sighs of relief.

Kvcn before ihe -new" engine series was brought out in 1907. an overhead camshaft experiment wa* instituted with it, utilizing a -tJa.sjsed block (it was never produced in that displace­ment). T h i s 1966 program was carried out mainly beeau«e then* was lots of interest for O H C VeH a t the time, and Buick wanted to find out its value. It didn't go far. as cost — that great equalizer - showed there wasn 't enough to he gained over a wedge design for the amount of momy required to pro­duce it. A nearly true hemispherical combustion chamber wan featured, and the valves were staggered instead of K ing 180 degree* apart. Object of this manner of design was to get a low surfaixMo-volurnc ratio. The camshaft

slipped in through the davisi-cncl tow* ors. and hydraulic fctsh adjusters and hydraulic chain tensioners were part of this design. A H components were cast iron, and the project did begin life with much thought >: i v i o to produc­tion. It never real nerd thorough testing, and the piece* seen in our photo* are the only ones in existence.

In I1s>s. .-mother rasing-type engine wtis realised from a 100-cubie inch VS. nod i U departures from stork were few. 'Ihe 4.*mm IKK* Webers and up* turned exhaust headers are the most visual ch.m;;. . Vnl\ . were enhirgis) Vt-ituU. and this later became stock s|>ecs on the G.S. engines. A great deal of this engine's rroaon for being was to help w o r k o u t CuS. pieces. The cam­

shaft used is very ckxe to present h y -rlraulic lifter assemblies in O.S. mod* els: and tubular pu«hmd*. like those in the "70 big Bunks , were first tried here. J forsepower was a respectable 445 at M(K> r pm T h e engine eventually wound up in .i <o i »|H t i t ion boat driven by Astronaot Pete Conrad in the Gu l l of Mexico, and this was very definitely a part id its testing.

Present cx|>erimentaf i<oi n wo Ives an extension of the current Stage I option. T h e underdevelopment Stage II pack­age has a cylinder head design radi­cally different from n luodurtion ])ieco. ]*oth intake and exhaust are changed, calling for special machining which doesn't come cheaply. A tunnel-port in­let is being con sick risl. but the easier-to build shape baa a relatively small tiorl whi<'h oj>enn up just past the p u s h r o d l oca t i on and become* very large by the time it reaches the intake valve. Kxhnufcl |*>it i lmgnt ttrv very c lose to the V A I V C S themselves, which IN tl»e ma>or m a c h i n i n g ope r a t i on , a n d |Nirl of the St .^e II prof**sal c a l l s for tubular exhau«t header* Much of the exhaust manifoMin,; design places the 2^-inch-insirle diajneser headers as an integral part of the exhaust porting, Buick s Dennis Manner has been herd­ing this project along, although lie hasn't yet l>een able to get in-car or dynamomete r testing accompl i shed . Other pro|K>sod parts in the Stage II project are an 850-cfm Stages) second¬ary (mechanical) Molley carh on an Kdclhrock intake, deep groove pulleys, oil sump windage tray, and a hydraulic valve (lain good for rpm. Purged rods on a nodular i r on crank, with forged aluminum pistons, might !*• the way the final flc*ign comes out M a n y c o m b i n a t i o n * are be ing MUggcnUsI a n d I rted on this r.»du .d c*|»ecially foi this group - Stage It.

J ' j ie long h i d d e n deve l opment WOlk .'it Buick besraase One of our must inter­esting project*. Seeing it all spread out sure got rid of any "reasonable, as­sumptions" wr might have had. s s

' • A Y 1970 • HOT SQD 3 5