[DeTomaso] automotive related questions!

[Thomas Tornblom]

MikeLDrew at aol.com skrev:
> 
> In a message dated 12/10/08 11 31 5, Thomas.Tornblom at hax.se writes:
> 
> 
>>
>> The mid 2 cylinders of each bank goes with the outer 2 of the opposite 
>> bank.
> 
> 
> And furthermore, in an ideal world, the pipes are arranged in the 
> collector so that the exhaust pulses rotate (either clockwise or 
> counterclockwise), for maximum scavenging effect.
> 
> Here's a drawing showing the setup on a GT40 with an early Ford firing 
> order (15426378)
> 
> http://www.gt40s.com/forum/attachment.php?attachmentid=25165&d=1194911751

An interesting fact is that the HO/Cleveland firing order will result in 
rotation in the other direction in the "right" side pipe in the picture. 
It will most likely work just as fine.

> 
> And here's a nice, easy-to-understand drawing of an original exhaust for 
> a 427 side-oiler (which uses the same firing order):
> 
> http://www.gt40s.com/forum/gt40-tech-engines-induction-exhaust/23396-pairing-headers-2.html
> 
> As these two drawings are unrelated, they don't exactly correlate--the 
> first diagram has 'left' and 'right' indications, but the second drawing 
> has them reversed.  It really doesn't matter which side the exhausts are 
> on, so long as the correct cylinders are paired.
> 
> In the 351C (and 351W), the firing order is different:  13726548.  So 
> although the two inboards from each side are paired with the outboards 
> from the opposite side, the routing of the individual pipes into the 
> collector needs to be changed if the rotational pulse scheme is respected.

Apparently it will only result in rotation in the other direction. The 
pulses will still be correctly sequenced.

> 
> Honestly though, I really doubt it makes much difference one way or the 
> other....
> 
> Mike
> 

Cheers,
Thomas