Inliners International Forums General Discussion Hi Performance 292 Sleeves

Howdy,I'm building a 292 and took it to a machine shop to have it board.They said it would clean up on .040.Now they say there are rust pits and they need to sleeve three cyclinders.This seames like a patch job to me.I have not built a high performance 292 will this stand up to hard use or even a turbo?Or should I get a different block? Thanks

I believe it is time to get a different block. It is best to use one for any performance work with the least amount of overbore. This leaves the block the strongest.

Sleeves are a wonderful way of converting bad judgment on their part (they bored it wrong, measured the size wrong, inspected it wrong) into a profit. You buy 6 sleeves at high mark-up, and have all cylinders bored twice: once to insert the sleeve, then to size the sleeve (although this could be honed if the sleeve is good).
Get another block, and don't pay them for boring this one.

If you are planning to turbo the engine say over 15# boost then you may want to install good sleeves on all 6 holes - this will prevent bore distortion over the long run. On the other hand if you plan on say no more than 10# boost then find a std. block and go the minimum bore possible. Get it sonic thickness checked before spnding any money on machining. You want at least 0.180" wall thickness more is better.

Not too sure if installing 6 sleeves in there would actually be stronger?

MBHD

http://www.dartonsleeves.com/mainpage.htm << no BS sleeves!

Thanks for your input. I think I have found a std.bore block to buy.

I'm not sure sleeves will be stronger either. Sure, the cylinder walls themselves might be but remember, the load between the cylinder head and crankshaft tries to pull the block apart. Sleeving removes original block material that would resist this loading.

I was sold a "good original" block that turned out to already be +.060 and rough, unusable....'65 292 block ....if anyone wants it you can have it. It would need to be sleeved.
Otherwise, it will be junked I guess.

Stroker,there are a lot of things to consider when installing sleeves in our sixes....a step should be left at the bottom of the bore and the sleeve trimmed flush with the deck; that way it is captured between the block and the head....although I've never had a leak at the deck I've always been concerned about the torqueing stress on the deck "pulling" the deck away from the sleeve (at the deck).....003 to .004 interference gives a good fit; unfortunately we can't determine movement after the head is torgued so how much is "lost" is a quess....sleeves will give a consistent cylinder wall thickness which will aid cooling ....flip side of this is if you have to pay to do this the cost goes up considerably; good 292 blocks are getting a bit scarce in our area so that becomes a factor....I've seen the SBC guys do a lot crazier things to save numbers matching blocks.....fats

Assuming the sleeve is dry (contacts the original block, and does not replace the cylinder wall and go directly to water), the temperature at any point on the cylinder wall will be higher for 2 reasons:
1. the thickness of the sleeve is less than the thickness of the original cylinder, which means that heat transfer by conduction away from a local hot spot (top of the bore closest to the exhaust valve) is reduced because the cross-section is smaller. A 3/16" wall transfers heat better than a 1/8" wall + 1/16" sleeve.
2. the interface between the sleeve and block, even at a high press fit, is always a thermal gradient which reduces heat transfer - heat does not pass through the contact point nearly as well as it flows through a continuous casting (although certain chemical coatings do help).

Regardless of bore size, sleeves, etc. the surface area of water contacting the cylinder's OD is a constant, so heat transfer to the jacket can't be improved.
I also have a gut feeling that the amount of press may differ between end and middle cylinders, and between 235 and 261 due to #3-4 siamese bore, etc.
This is not only very precise work (far worse than simply boring) but differs between engines. If the press is too high or the sleeve OD is too large (LASCO will make one for you), the block will crack. If the press isn't enough, you may get head gasket or water leaks.