bore ques
#1
bore ques
im building a 383 and i'll be using forged pistons. my bores vary from 4.030 to 4.032. from what im understanding i can make that 2 thou up in the rings. my builder is strongly insistent on possibly going .040 so all of the cyls will match.
this eng will see some open track day stuff, auto x, and a random pass down the strip but mostly street driving and no power adders.
i got the block some time back and the guy had it already prepped and decided to go another route so he sold it to me for $350. he had a rotating assy but i didnt buy that as i wasnt ready for that at the moment, i was getting a bunch of other stuff together first. plus where i work i get a wicked discount on my parts. i jumped on this block due to the cost.
this eng will see some open track day stuff, auto x, and a random pass down the strip but mostly street driving and no power adders.
i got the block some time back and the guy had it already prepped and decided to go another route so he sold it to me for $350. he had a rotating assy but i didnt buy that as i wasnt ready for that at the moment, i was getting a bunch of other stuff together first. plus where i work i get a wicked discount on my parts. i jumped on this block due to the cost.
#2
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Re: bore ques
You could make up ALOT more than .002" in the rings, if that was all that mattered.
Where you'll have trouble is, piston to bore clearance. They'll fit differently: depending on what kind of pistons you use, some may be OK, some may be too tight, some may be sloppy loose.
Sounds like an overall sloppy prep job, or just already significantly worn. If that's supposedly "freshly machined", it's A TOTAL MESS.
I'd strongly consider having it index-bored (i.e. each cyl bored where it's perfectly centered as opposed to "on the wear"), then honed with a torque plate.
Where you'll have trouble is, piston to bore clearance. They'll fit differently: depending on what kind of pistons you use, some may be OK, some may be too tight, some may be sloppy loose.
Sounds like an overall sloppy prep job, or just already significantly worn. If that's supposedly "freshly machined", it's A TOTAL MESS.
I'd strongly consider having it index-bored (i.e. each cyl bored where it's perfectly centered as opposed to "on the wear"), then honed with a torque plate.
#3
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Re: bore ques
If you don't own the pistons yet, buy 0.040" over pistons and take them and the block to the machine shop for proper fitment. Any machine shop that bores a block without having the pistons to check fitment isn't doing a good enough job.
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