Quote Originally Posted by ZR View Post
Ok so rules out stretched chain or similar, might want to review combo as I suspect there is more h/p n t/q hiding there somewhere.
Glad you said it. My car made 315whp with my Comp 262s which are a similar cam and didn't fall off power that early. My setup at that time was Comp 262s, C&L plenum, 75mm TB, JLT cold air, ORX with stock manifolds and Flowmaster mufflers. I went one heat range colder on the NGKs plugs, OE Motorcraft coils, aeromotive 340 pump, stock injectors and rails. Car was running Shell 91.

Feel like either the car isn't getting enough air to make use of the cams or something else is amiss.

Things to check are TB/Plenum. If you have a cheapy TB and plenum combo CHUCK EM for a good Accufab combo or C&L.

Intake manifold. If you have the Dorman (integrated gasket) replacement manifold THROW IT IN THE THE TRASH IMMEDIATELY. I lost 10hp at peak and 3 tenths in the 1/4 on a Dorman vs the FRPP replacement intake manifold.

Air intake. I found the big JLT in fender setup made the most power on my N/A combo vs anything else I tried (K/N/Steeda/eBay) and showed best average IATs on my scanner.

Cats if they're an old mid pipe setup might be good for a few HP vs a modern GESI high flow.