Cam lobe positioning

Whittle V8

Firing order and engine rotationThe given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

Front

1& 27& 8

3 & 45 & 6

Flat plane crank

1,2,7,8

3,4,5,6

1,3,5,7 2,4,6,8

Piston 1 at TDC in Cyl. 1 Piston 4 at TDC in Cyl. 4

In order to fire every 90 degrees, the crank rotation must be anti-clock from front.

Cam lobe position relative to Cylinder 1The given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

This is a 90 degree V engine:-

Even cylinder Pushrods meet the camshaft at 90 degrees to the Odd cylinder Pushrods!

Crank rotates 90 degrees Anti-Clock to nextfiring position

Camshaft rotates at half speed, so45 degrees and Clockwise to next firing position

1

1 4

Piston 1 at TDC in Cyl. 1 Piston 4 at TDC in Cyl. 4

4

Rotates to this positionWhen Cyl. 4 is at TDC

Pushrod on cam heels

1 4

Pushrod on cam heels

NB. Compare these two profiles with EW drawing for 1 and 4. They are the same!

45 deg.

90 deg.

Crank rotates 90 degrees Anti-Clockto next firing position

Camshaft rotates at half speed, so45 degrees and Clockwise to next firing position

Cam lobe position relative to Cylinder 1The given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

Cam lobe positions relative to Cylinder 1 firing position

All cams Rotated 45 degrees Clockwise for ease of comparison to EW drawing

Comparison to the original EW drawing

For ease of comparison all cams have beenRotated 45 degrees clockwise.

Now when we compare each cam to Eric Whittle’s drawing, we see they are identical!

Working the Firing order through

The given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

Working the Firing order through

The given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

Working the Firing order through

The given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

Working the Firing order through

The given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

Working the Firing order through

The given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

Working the Firing order through

The given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

Working the Firing order through

The given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

Working the Firing order through

The given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

SummaryThe given firing order by EW is: 1, 4, 3, 8, 7, 6, 5, 2.

To meet this firing order, the engine rotation is Anti-Clockwise looking from the front.

Camshaft rotation is Clockwise from the front.

The Cam lobe positions shown on the original drawing are correct to meet the suggested firing order.