Cool bore v.s. Steel sleeve (any advantages to either)

M

mattf76

Member
Hello,
I have a few nice block around that are cool bore engines. I typically run steel sleeve bores just because they seem to last longer with the dirt even with good clean filters changed every race. Is there an advantage to either besides better wear and longevity..? Also I can sleeve these aluminum blocks without a problem, what do you guys typically run for interference for sleeve to block.
.001"-.0015" more or less?
Thanks,
Matt
 
You said it , longevity. but I like which block flows the best and will build that one and/or sleeve it . .001 interference works fine, I use to leave a little step at the bottom of the bore when fitting my new sleeve and after sweating the sleeve in I put a 20 lb weight on top of it because sometimes when it cools it can move up on you a little, the top of the sleeve sticks up then fly cut the excess of the sleeve off down to the deck.
 
Thanks Gearhead. I've sleeved some sled and dirt bike jugs before. typically used that interference. My biggest question was that of the differences in alum and sleeved bore. I also had a block that was sleeved once and had a small step in bottom. That is how I would also do it. And how I've done it. To me it contains the sleeve in place from falling should it ever happen. Appreciate the reply and info.
Thanks,
Matt
 
I don't believe .001 is enough for installing sleeves. The method I used and never had a problem was to bore the block .003-.005 under the sleeve OD, heat the block in a 450-500 degree oven for 10 minutes and drop the sleeve in. I did leave a step in the bottom of the bore so the sleeve would not drop through. -- Chuck
 
I'm with Chuck we setup for .003 for sleeving


between the two block is one better not really

cool bores wear a small bit more than I/Cs but I/Cs tend to warp way more and you end up honing a lot of clearance out of one to get it back straight. but if broken in correctly they can be quite good and hard as a brick..

now anew cool bore sleeved with larger OD sleeves tend to be the best deal not to mention you can control where the sleeve is set and at what angle relative to the crank centerline and end up with a STD bore you can use


lots of differing opinions on the above by some very good builders
 
Thanks for all of the replies. Really Appreciate it. Also is there any advantage to tipping the top of sleeve toward or away from the valves..? i.e. I will be boring this on a mill setting up with a dummy crank. I can shim the front or back of block to make the cut. Just curious if anyone has seen any advantage to doing this.
Matt
 
I never could justify the trouble based on the dyno I had . I did a couple then quit trying . I even ordered a few blocks from ARC that had angle sleeves to see and try to copy their chosen degree . ARC had a write up about which way to angle the sleeve which they said could move the torque curve slightly one way or the other. I like straight as a laser beam myself with a angle deck.
 
With a .001 interference I use EZBORE fluid weld and/or Loc tite high temp retaining compound on OD of sleeve , heat block in oven or i have used a rose bud and drop sleeve in put a heavy weight on top to hold it down while it cools . No stresses and nice straight bore a lot of times i get to start back over with a standard bore piston.
 
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