Lt1 bored 60. Over
If you already have a forged bottom end, spray it and have fun.
But that's my $.02
Seems like too much attention given to valve lift (which means VERY little!) and not enough to quality and acuracy of cylinder wall boring & honing, fit & finish of piston ring lands and ring selection. Ditto start up & ring seating & break-in.
What do you know about the machinist that bored and honed the block?
I have had a couple of customers that race their LT1s at the track regularly, and I tuned on my dyno. Both cars were 100,000 mile factory short block F body cars. Heads, cams, headers, etc. They rebuilt them, using a local shop & guy that bracket races locally. Bored .030" over. Both cars slowed down. They both brought them back to me for "re-tuning" (should have been no need, nothing else was changed.) one car was down 18 rwhp, other one was down 30!
I would never buy one when I didn't know more about it. A lot of you guys here are looking for power in the wrong places.
To op
I agree with ed, you should be making a lot more power. You either should do research on engine building theory or let someone, who has built an engine that is comparable to yours that makes great power, do the building for you. Lots of people here can help you but you will definitely need an open mind and be able to swallow your pride.
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But, I have seen 383"s that would not make 300. Not all "built" short blocks make as much as factory short blocks. Many don't realize the factory piston & ring set up is better than what they are putting in their builds. Narrower lower tension rings and better machined & finished ring grooves. Stiff, heavy rebuilder rings cost power.
Not all (most) machine shops can deliver round enough, straight enough cylinder walls with the correct surface finish. Takes more than a torque plate and an old Sunnun CK10 hone. The best deal right now is a Rottler Diamond hone. Absolutely makes more power. Improved ring seal is worth a ton more power than more valve lift.
If you are trying to build a fast one, CP or Bill Miller are hard to beat. My long time Pro Stock racer friend Mike Edwards uses CP in his race car. That is also what is in mine right now. Piston rings, pretty much the standard is Total Seal, but nobody I know uses their gapless ring.
If you are trying to build a fast one, CP or Bill Miller are hard to beat. My long time Pro Stock racer friend Mike Edwards uses CP in his race car. That is also what is in mine right now. Piston rings, pretty much the standard is Total Seal, but nobody I know uses their gapless ring.
Do NOT use a high volume oil pump! One of the dumbest things I see done.

