I will be putting a 355 together to put in my 85 Camaro former little old lady driven to church on sunday car. The 355 short block will be assembled with stock crank and reworked rods with speed pro dome forged pistons and a comp cam 501/244 hyd cam & 1.6 rockers. This vehicle will see limited street and an occasional trip to the track, what i am asking for is what compression ratio will work best with this combination my choices being 12.94 11.87 11.26 10.71 and 10.22 compression the rest of the engine consists of torque II manifold (Hood Clearance) not my first choice and a 750 holley dp carb thanks

 

Wow...

I hate to be such a buzz-killer, but that's EVERY SINGLE 70s-80s smogger mistake you can make, all balled up into one.

I'm guessing this is going to have the "stock" heads? 882, 993, or 624, perhaps?

Dome pistons and big-chamber heads are a GUARANTEED inefficient, detonation-*****, fuel-finnicky, VERY EXPENSIVE to operate slug. There is no worse combo you can create in that area.

501/244 is lame. Even the "RPM cam", with the same .050" duration on the exhaust, has more lift than that. What you'll end up with is a motor that has no top end whatsoever, because of the smogger heads; and no low end whatsoever, because of the long-duration cam. An all-around slug.

The T2 manifold was one of Edelbrock's first attempts to combine a single and a dual plane intake. Didn't work. What they got was all the disadvantages of both, and the advantages of neither. It will AMPLIFY the poor cam choice problem.

That's just not a good plan. A flat-top motor with 64cc heads will KILL an otherwise identical (cam, intake, exhaust) dome-piston 76cc head motor of the same static CR, EVERY TIME, no questions asked, no other outcome possible, case closed, period. Given the proper machine work (zero-decking the block to the pistons), the disparity gets even greater.

Ditch the smogger heads. Get a set of 64cc heads, Vortecs maybe even. Pick a different cam: for a 350 on the street, a Comp XE268 is GREAT. Ditch the T2. Get a Performer RPM for Vortecs.

{edit} I almost forgot... for the street, you want NO MORE THAN low 10s CR with iron heads, and that IF AND ONLY IF the block has been zero-decked to the rotating assembly. If the block is not zero-decked, you want NO MORE THAN mid 9s. So really, none of those pistons is a good choice.