equal length manifold vs log manifold

[ashills]

found this on the sr20 forum
http://www.sr20forum.com/showthread.php?t=84358

60bhp more with a equal length manifold
but slower spool probably due to longer pipes maybe ??

 

[AJ4]

I always thought an equal length manifold would give a higher peak power but over a narrower range, like in a circuit car. Unequal lengths tune the torque curve for each cylinder to different rpms, which flattens the torque curve out ( making the car accelerate faster but have a lower bhp )

Thats for NA engines anyway, not sure how the whole turbo thing affects it :?:

 

[kyepan]

quality info, are their any specific GTI-r equal length manifolds? i know there are the 200sx ones..

 

[kyepan]

double post

 

[Fast Guy]

RESULTS: SWAPPING MANIFOLD = ~68.3 whp peak gain before tuning, ~48 whp after tuning, ~49.7 ft/lb before tuning, ~44 ft/lb after tuning

So they lost 20whp by tuning it????? I wonder if the car was fully warmed up before the first run as you're not supposed to loose power by tuning something. Even so, 48whp is a good result

 

[Nad]

RESULTS: SWAPPING MANIFOLD = ~68.3 whp peak gain before tuning, ~48 whp after tuning, ~49.7 ft/lb before tuning, ~44 ft/lb after tuning

So they lost 20whp by tuning it????? I wonder if the car was fully warmed up before the first run as you're not supposed to loose power by tuning something. Even so, 48whp is a good result

But that depends on where the power is produced. If it is lower down then that would produce a lower top power but offer better response.

Nad

 

[Fast Guy]

If they made power lower down, they should have made more torque not lost that as well.