N/A my 557ci made 955hp (Methanol injection)w/ 345cc CNC'd -1's that flow 382 at .800 these are Jeff's from Modern's program.

Cam is .875" (less lash and deflection)so i am opening them up as far as reasonable

Car weighs 2,850 and at 4,000 foot DA ran 8.80's, but there is more left in the combo...

If you want more than that N/A you need a better head IMO.

Cheers,

Arnie

67 Cuda 8.48@ 158.7 mph 1.18 60' 2,600 DA(so far...) 70 Super Bee 440 Six Pack 4-speed. 13.2 @ 104 Stock exhaust/Street tires.