The sportsman pros do work well when pressured down and get better as some of the new tread is burned off.
They will work well for you.
Get your money back on the 882 heads. Not worth anything. "worst of the worst SBC heads" even when ported.
The 920's are a pre 1975 better choice open chamber 76cc smogger. (better, shaped and larger as cast ports, single heat riser, heavy casting, better when ported too)
5.13's can work with a 31" tire. (N/A combo) A (big solid lifter) cammed motor wants to rev.
Many of the flat tops piston eg: H345NP have a fubared compression height (1.54") resulting in a big piston to deck clearance
@TDC and less cr. .045" ++ deck clearance on a non decked block. something to look for before you tear the motor down.
Always measure the assembled deck clearance before tear down. Then you can measure the true pin height and determine the block deck height.
re: .045" deck height ...not such a bad thing when you want a low compression ratio blower motor.
blower friendly 7.87:1 with 80cc heads (deshrouded 76cc smogger heads) + .051" corvette gasket
Just use generous larger rind end gaps for high boost applications.
Last edited by F-BIRD'88; 12-05-2012 at 10:41 PM.