Hi folks, i am rebuilding an sbc, the block is from era 80-85, 350 4 bolt main, passenger side dipstick , the heads are 305HO, 58cc combustion chamber out of an monte carlo 86, and the crank, connecting rod, piston and the other things are from an chevelle 74, my question is the following which engine torque specs should i use? since none of the parts are all from the same engine nor same era?
Eric
I'd use the 80-85 specs and dump the 305 heads. you're just begging for detonation from the sharp edge due to the 305's smaller bore.
-Bret
the reason i chose thoses heads was due to their small combustion chambers (58cc) therefore givin me a better compression ratio then a normal 350 heads with a 76cc chamber, was im wrong?
Eric
No you're not wrong, but I think that Bret's warning is that you don't increase it to much just by the heads. What he's referring to is that the head is designed for a smaller bore, that's why the 58cc chambers. As well the valves will be more in the center of the bore rather than spread across the cylinder diameter. Could be it won't get a good even cylinder fill also, hurting combustion and hence detonation.
Brian
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