Well I am about ready to put the new 355 together. I thought I would revisit cam selection one final time. What I have is a 2 bolt main, cast crank 355. Pistons are speed-pro hypereutectic 11.93 to 1 (with 64 cc heads). Cylinder heads are 336's with 2.02 valves and 76 cc chambers or I have a set with 1.94 valves. My choice of cams that I have are a Crane H074 (.450/218@.050, 106 lsa) or a Crane F-244/3454-2s-6 (.518/.536, 244/252@.050, 106 lsa). Intake will be either Performer or Performer RPM depending on cam selection. Car will be either 600 cfm edelbrock or 770 street avenger. Car has turbo 350 with 300 stall and 3.36 gears. Car is not a daily driver but will be street driven on weekends. Any input is appreciated.

With the 11.5 comp 64cc heads you'll need the bigger cam profile to bleed off some cylinder presure. You still might run into trouble with detonation. If you go with the 76cc heads the small cam might work better, but, looks like the duration is too short and may cause detonation. I would run the Performer RPM in either case.

Good Luck :D

Well....depending on a few things like actual piston dome, deck height and gasket thickness, the 76cc head you got should bring compression down to around 10.3:1......depending. If you have the piston dome specs, that would help(how many cc is the dome). It would benefit you to run more gear. With that much comp you would benefit with a descent sized camshaft.....and "said" camshaft will like more gear. Plus, it will help detonation issues as the motor wont be loaded as hard with more gear. Probably no less than 3.73's. If you like a hydraulic cam, Id look for something in the neighborhood of about 230-236 degrees duration at .050.

However, if you can have those domes lopped off a bit to get compression a little under 10:1, your first cam selection would work rather well except I dont like the 106 lsa for this motor. Id use a cam of very similar specs but a 110LSA, about 9.5:1 comp, your current gears and a little bit of head work. It would make things easier. You could keep the compression as is.....but the large cam will call for more gear in a 355 chev to really come to life, and your getting into territory where better heads would really help cause of the fact that the larger cam will like to rev(And want better heads to do so) as well as wanting more gear. Id try to bring the comp down......or keep it as is, but run a small enough cam to work with your heads and gears and deal with having to most likely mix some higher octane(non pump gas) fuel to keep any sort of pinging away.

Thanks for the input. For the record, both sets of heads that I have are 76cc chambers. The set with 2.02 valves has screw in studs and guideplates so I would prefer to use them over the 1.94's. The block has not been zero-decked and gasket thickness should be .038 to .041. The dome is listed as .275 and 11.8 cc's.

http://store.summitracing.com/largeimage.asp?part=STL-H617CP30

I figure compression should be between 10.2 and 10.5 to one at most. Didn't some small block chevys come stock with 10.0 to 1 and really mild cams specs. (such as 350/300hp and 327/300hp.) I will probably have to live with the gearing and the heads for a while so I want a cam that will perform pretty well with what I have right now.
Thanks and does anyone else have any input?

bump...anyone else have any input?

I'm running a 402 ci that makes 10.1:1 comp over a Clevite hyd cam 240/246 durr @.050, 559/572 lft, 112 LSA, Holley 750 cfm dbl pump carb, Edelb perfm RPM heads & manifold. No ping at all with 93 octane gas. First dyno'd at 443 HP @ 6000, changed jets and now get 463 HP.