I am redoing my 385 LT1 that is bored 40 over. I am now going 60 over after having sonic tested with fairly optimistic results. I was first going to sleeve the block to go with a larger pistion size and was told that it is impossible in a practical sense. Basically if you were to do it the sleeves would fall out of place under any substancial load. A machine shop reluctanly offered to do but said there would be no warranty and that it would likely fail.

 

Why go to .060 over for fewer than 4 cubes and about 5 hp 5 lb-ft if you do it right?

It's about time for a new (old) block. How about just going .030 over which will give you a .010 clean up the next time you rebuild. Whatever you decide, don't use a shop that predicts failure. Their prophecy will be self-fulfilling.

Free advice....and you didn't ask.

 

Am I missing someting here. I thought any block could be sleeved? How are the sleeves going to fall out with the head in the way? I'm ignoring cost or practicallity here.

 

He's already .040 over.

 

Yeah, I got the "4 cubes" (3.82) number going from +.040 to +.060.

I was just wondering why a .040 over would WANT to go to .060 over on an LT1 with all the possible problems just to gain a few cubes. If it has enough miles on the +.040 to need a another rebuild, IMO start all over again.

Of course the block could be successfully sleeved, but why bother? There's something about pouring money down a rathole...

 

Well, there is the fact that the block is well seasoned by that time. Plus you might have done some work that you want to save. Perhaps a 4-bolt conversion or a polished lifter valley.

I'm not saying that's the case here, I'm just playing devils advocate.

There's one more thing...
With a sleeve you might be able to get better ring seal.

 

Most LT1 blocks are 9 years or older. That's more "seasoning" than many good bourbons get. Just think about all those LT1 Roadmonsters driven by little old ladies and gentleman now starting to turn up in the recycle yards.

Eight sleeves done well by someone like WWW.CNCBLOCKSNORTHEAST.COM wouldn't be cheap. Having a used LT1 block fully prepped by them in all areas like bore location, lifter bore location, steel main caps etc. and keeping it to +.030 would, IMO, be a much wiser investment than sleeving to get to 4.060.

"An idle mind is the devil's workshop." Yours isn't idle, Lame.

 

You know, I can't help coming back to that same old question...

Is it even worth it to build an engine anymore?

I don't mean for hardcore racers, I mean for hobbyists.

 

I've thought about this alot myself, and for me it comes down to a simple question who's answer I must make sure I'm always honest with myself about: does my speed dictate my ego, or does my ego dictate my speed? The distinction in answers is subtle, but their implications are far reaching.

It's still worth it to me, but of course this is coming from a lowly hobbyist who's ego has never quite managed to catch up to his speedometer...

 

If I remember right someone said you can get a set of diamond pistons or something like that, for like .042 or .045 over or some custom number, probably cheaper than sleeving. Unless your dead set on 60 over.