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#21807 03/05/02 09:14 PM
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this is just to kill some curiosity I have. what are the effects of this in a racing circumstance? Is block rigidity increased? Do the metals used for sleeves hold more heat in the chamber. How big of a bore can be acheived with sleeves in a 292? do they hold up well in engines with extremely high cylinder pressures. Have any of you done this to your inlines with success. Haven't really been able to find anything on the net. thanks for the replies

#21808 03/06/02 02:45 PM
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Sleeving is a way of saving a block, I don't feel it has any effect on rigitity one way or the other. The material in a sleeve probable is a more consistance throughout than a cast iron block, i.e. less likely to have hard spots. I wouldn't use sleeving as a means of encreasing a bore larger than can be done safely in the block. More heat in the combustion chamber? It would take a lab to measure any encrease, there will be a small heat barrier at the sleve/block interface, but nothing to worry about.Besides, practicle none of the sleeve is exposed to combustion, by the time the piston has uncovered the sleeve combustion has already taking place. The combustion temp and pressure will be highest while the piston is near the top of the stroke and they will decrease as the piston fallls in the cylindar. I've had numerous blocks sleeved over the years and never had any problems. One Cortina 1300 engine I built turned 10K with sleeves in all holes. Hope this helps. Bob

#21809 03/06/02 05:27 PM
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The material in a sleeve is generally better than the iron a block is made of. They come in 1/8" and 3/32" wall thickness. The thinner 3/32" sleeve is for saving blocks with gouged cylinders where you wish to keep a dry installation ( where you don't wnat to break through the water jacket). The thicker on is for a wet application, although a dry installation can sometimes be achieved. The 1/8" wall is equivalent of about .200 thick cast iron. The structural rigidity is weakened some. The cylinders basically connect the deck to the bottom of the block. When you torque the head after installing a sleeve you will often hear strange noises like cracking and popping as things shift around under stress. Some guys go as far as wet sleeving all the cylinders to get a larger bore size but the block is weakened substantially. You also run a good risk of an internal water leak with a wet installation.

#21810 07/27/07 04:44 AM
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so is it safe to say that you could sleeve a 292 block for 4 inch pistons to make 312 cubic inches with either wet/dry install for a street motor that will not ever turn over 5500rpm, with like 9.5:1 comp ratio and like 270 dur cam?


you can lead people to truth, but you can't make them see it!
#21811 07/27/07 07:40 AM
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I think the main problem you would incounter is the distance between the cylinders, you simply won't have enough for a trustworthy head gasket seal. It has been done though, the Duggan blocks are siamised and can go out to 4.125, they have the same cylinder bore spacing.

#21812 07/27/07 11:54 AM
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Gentlemen;

This type of experiment, is just that and done by racers for the track etc.

You wouldn't want to do it for 'street' use.

A +.060" overbore is plenty for the 292. The added compression with flat pistons, is what makes it run.

There $600 and you wouldn't want them in a weak block etc.

Happy trails. \:\)


John M., I.I. #3370

"There are no shortcuts to any place worth going". -Anon
#21813 08/06/07 01:51 AM
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54Chevy, to answer your curiosity, on our race motor we use sleeves as a surrogate bore surface to cut down on friction in the engine. Ours are a special thin wall sleeve that is made in the U.K. and comes with less than 1mm wall thickness. Our engine is a GMC 302, 60 over.

After hot honing our blocks to replicate running temperatures we found that it is still had distortion in the cylinders and also we were not able to put the desired profile we wanted to have. With the sleeves we were able to put the proper taper and profile before installing them. Even though hot honing takes most of the distortion out, we were able to further reduce friction by manipulating the process by hand to put the required taper and profile in the liners. These are dry installed and we used a Nickel-Ceramic plating giving it a ‘oleophilic’ finish with low friction (Ra 0.15-0.30). With this coating we also had to use a Titanium Nitrade coatings on the rings.

In the reciprocating piston environment where relative velocity changes greatly, it is not possible to modify pressure greatly without effecting performance. But by manipulating and modifying the surface roughness we can alter the effectiveness of the lubrication to cut down on drag. Being in Silicon Valley I had some of my engineering friends use computational fluid dynamics to develop a computer program that predicted how the oil film will behave and we were able to validated this by using ultrasonic transducer technology. We have found that this did reduce ring friction. How ever if it is not applied properly it can be detrimental to the engine.

It is not straight forward as it sounds and it is extremely expensive and a lot of work, but in our case we are looking for every last horsepower we can get.

#21814 08/27/07 01:20 PM
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See hot rod engine annual , article on free standing sleeves in 6.1 new style hemi block. Interesting and worth a look as it is exactly on the subject you are talking about for the same reason but just a different engine.
We run half bored blocks to strengthen them when we push the limits. The shorter a cylinder is the stronger it is so by supporting the lower half we can make a huge improvement in strength. Interestingly enough the engine we have been working on does not run hotter, in fact this weekend racing it never even got to 185F.
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#21815 08/30/07 09:33 PM
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I am sorry. Should be, we run half poured blocks(aka short fill)

#21816 08/31/07 11:08 AM
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In the 80's some top Nascar engine builders would sleeve Chevy V's,they claimed it made a more rigid block that would take abuse from detonation better,as in not crack cylinders.
Generally speaking,most stay away from sleeving on street engines,head gasket issues as mentioned above.


70 Triumph 650 cc ECTA current record holder
#21817 09/01/07 09:49 AM
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Re hot honing etc
I h finsh my cylinders with the head installed from underneath. Mind you I use a sunnen hand Hone with the super fine stones and the material removal is very light but the bad areas of the bore where distrtion takes place showed up immediately and we were able to cure it this way. I do it only on my serious race motors as it is a pain to do. Hand honing takes a few years to get good at. I never tried it with a power hone but it is probably possible.I prefer this on our engines to using torque plates which "sorta" mimick the head. I believe that nothing mimicks the head better than "The head! I was never gonna tell anyone but oops there it is out in the open.


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