I have a procharger on my 03 z, Planning on doing 600cc injectors, fuel return system, osiris, 255 fuel pump, full dual exhaust with test pipes. What upper plenum is reccomended if any?

 

hmm i recommend a search. To start its free to! Try, cosworth/kenix/motordyne(spacer). Those are some names to search on, Good luck.

 

look into that, best bang for your dollar, but yeah def. search

 

Don't forget the Crawford plenum.

 

No it is not required. Most folks at least put a spacer on to equalize air flow to the front 2 cylinders. You will not gain much moving to a single larger plenum but it is easier to take on and off instead of stock+spacer. Cosworth has only 8 bolts and allows easy access to the spark plugs. Don't buy a plenum for power imo. I recommend a Motordyne spacer - best bang for the buck.

 

/\ /\ /\ Yeah you ain't kidding. Love my Cosworth.