A recommedation can be somewhat straightforward except that you mention that the heads have been "ported and polished". A little clean up won't matter much, but if the flow potential has been increased alot, say from 200 cfm up to 240, this may impact your cam selection.
Based on your repsonses I would suggest any of the following;
- a factory 068 grind (the RAIII auto) with 1.65 rockers
- a summit 2801 with 1.5 rockers
- a comp cams xtreme energy 51-222-4 with 1.5 rockers
These combos result in approx .450-.460 lift and around 215 intake and 225 exhaust duration at .050" They will not kill your low-end torque with 8.4 CR and still rev to 5200 rpm, with a torque peak around 2500 rpm. The comp cams choice will probably give you a bit more dynamic CR for throttle crispness, but at the expense of a little top end power.
If you go to lifts beyond .470 you won't gain anything, and if you go to durations in the 230/240 range you will push your torque peak to 3000 rpm and lose that good low-end "feel" which is necessary for street driving.
Way too many people over-cam their engines, kill their low-end torque and actually make a slower car all for the sake of a cool rumpity idle!
I don't claim to be the "cam-doctor" so if anyone else has a suggestion please post!
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