Help me out my fellow Z drivers...

Im leaning towards a Cosworth Plenum, I know its costly but after adding up a new lower and upper aftermarket plenum the cost for the cosworth is 500$ more...So my question is- If I get a Cosworth Plenum, I loose the lower plenum or do I still need it ??

 

The Cosworth replaces both the upper and lower portions.

 

Ok thx, does it offer the same HP gains as a spacer?

 

On an NA it should although it hasnt been proven yet. Ive seen it first hand and its a gorgeous well made piece. Get it and post before and after.

 

Supposed to be more and across the rpm range.

 

Thats a good question, I think the answer lies in the level of the car's build. If you can flow enough air "through" the motor I think it should at least be as good. From the Coszy website they show some impressive gains from the plenum alone (not sure if this was with a reflash or not) and very impressive gains when tuned and matched to the ported heads and cams. I'm really considering one myself.

 

 

Its worth the extra $500 for the looks it provides

 

The Cosworth plenum was designed with forced induction in mind. As a result, our most impressive gains have all been on forced induction applications. I cannot speak as highly for the results on naturally aspirated setups. It will flow as well as a 5/16" Motordyne plenum spacer.

One particular single turbo setup had gains of ~40 whp over a stock manifold throughout the entire upper portion of the powerband. This is not guaranteed for every turbo setup, but it does have the capacity to drastically improve airflow at the higher end.

If anyone has any setup-dependent questions regarding the Cosworth manifold, feel free to email me directly at ryan@injectedperformance.com.

 

oops wrong thread