Quote:
Originally Posted by GregWeld
I didn't look at either of the cam choices before making my comments about lazy bottom ends.... My comments were more GENERAL about cam choices, and people tendencies to use the "if a little is good - more is better". It's pretty much the way we all think.
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I agree Greg. Most people pick way too large of duration for street cams & the overall power is poor ... especially in the range we drive them on the street ... from idle to 3000. I was always amazed at how many "hot rod guys" would pick a race style cam with a powerband of 3500-7000 rpm .... then drive it on the street 90% of the time below 3500 rpm.
Joe, I was a Pontiac guy as a youngster and these 400" engines make good power from idle to 5000 ... as long as we don't mess it up with cam selection. If was driving the car myself ... often ... on the street. I personally would pick the smaller of the 2 also. The larger one will make the car faster, but the side effect will be the idle to 1800-2000 rpm range will not be as strong, nor as smooth.
With the smaller cam, I think you'll need to keep the compression around 10-1 to avoid detonation. Any higher & you'll probably have detonation issues. Any lower & you'll give up power & efficiency.
If you ever desire to build a more racy Pontiac ... you'll need different heads.
Best wishes.