View Single Post
  #3  
Old 02-02-2015, 01:19 PM
ArisESQ ArisESQ is offline
Senior Member
 
Join Date: Aug 2005
Location: Los Gatos
Posts: 765
Thanks: 8
Thanked 10 Times in 9 Posts
Default

Quote:
Originally Posted by Yater View Post
Hi guys,

Not planning to put onese in my car,

But just wondering out of curiosity:

I see there are a lot of aftermarket headers leading to 4-in-1 exhaust manifold configuration on each side. I think many brands claim gains on horsepower.

However, since these are aftermarket (hence I assume "generic"), how do we know, apart from testing on the dyno, that the design (lenghts, etc) does not harm rather than benefit the performance?
I may be totally wrong, but in order to bring extra performance, it should be very well tuned with the valve timing of the engine, otherwise the pressure waves reflected at the junction could reach the cilinder exhaust ports at the wrong timing and penalize performance rather than help, isn't it?
The solutions being "standard" for different engines, heads, cams... i wonder about it.


Again, not willing at all to discredit the benefits claimed by manufacturers who probably know very well what they do, it's just out of curiosity.

While some headers may perform better or worse than other headers, from what I've seen, all headers seem to make more power than stock cast manifolds.

So while there is likely a little tuning and research that needs to be done to optimize the performance of a header on a particular engine, I think you'd be seeing an improvement over the stock manifolds no matter what header you end up choosing.
Reply With Quote