[Jay S]

Originally Posted by ponjohn

Question is why?

The power gained from a 1/2 point won't be that much.

With the same cam that this absolutely true. With a well matched cam we have seen very little improvement in performance from the increase from 9.5 to 10. Where we find the gains is when you increase the cam size to match the compression. Then add extra head flow in combination with the bigger cam and head flow and it makes the hp gains much different. Stock heads you can easily run out of cam and head and the compression just makes it miserable to tune.

Cams have compression ceilings where the hp more or less levels out to. We have done many of the 2801 summits type grinds (214/224) profiles, after 9:0 on a 400+ Cid engine size the performance gains we have seen where small. I have had the 204/214 cam in a couple 440 mopars at 8.2 and 9:1. The 8.2 ran every bit as good as the 9. In fact with headers the 8.2 would take the 9:1 engine with manifolds. Lost track of the over 10:1 engines we have done. We keep pushing higher on cam size and head flow to see were the limits are for compression I honestly do not know where it is. My 452 cid fully ported 6x head combo sitting at 10.5 scr with a bullet 300/308, 245/253 @.050 with a 114 lsa, .630/.630. It is a solid roller on a hyd profile. Tim at bullet helped set it up so we can move the lash around to see what the engine is wanting. My biggest effort on a pump gas cast iron headed Pontiac so far in a roller. Biggest solid so far is a 256/264 at .050 w/112LSA solid flat tappet, it would go well into to 10s scr.

Putting these bigger cams with good heads, drag radials and the super eff tight 9.5 converters and you go from keeping up with a Toyota Camry to giveing a Hellcat a run for the money. More fun to beat the Hellcat.