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View Full Version : Sleeved STI block OMG



ElScooby
11-03-2009, 12:05 AM
Holy sleeved block Batman!!!!
An awesome build I have been following for a while.
http://www.iwsti.com/forums/other-vehic ... ar-61.html (http://www.iwsti.com/forums/other-vehicles/154064-pics-sleeves-post-607-team-rd-27-gc8-sti-race-car-61.html)

Stock
http://www.teamrd.com/wp-content/uploads/2009/10/sleeve1.jpg

Old Sleeves removed and custom one piece monster installed.
http://www.teamrd.com/wp-content/uploads/2009/10/sleeve2.jpg


I also just wanted to make a quick point about how my sleeves were done, because frankly, it was damn impressive.

Normally, you bore the stock sleeves until there's almost nothing left, like this:
http://www.justiceracingengines.com/services/images/Subaru%20EJ25%20ready%20for%20sleeves.jpg


Then you insert "sleeves" that fit inside of the stock aluminum ones:
http://www.justiceracingengines.com/services/images/Subaru%20EJ25%20Darton%20sleeve%20conversion.jpg


The problem with this is that you end up with a cylinder that is made out of two different materials. The stock aluminum (outside) and the cast iron (inside) expand at different rates and temperatures.

With my block, an engine machinist with 30 years of experience made 1 piece cast iron sleeves that get inserted directly in to the block. The existing stock sleeves (cylinders) get completely removed. This allows for extremely tight piston clearances without having to worry about the different expansion rates as the entire cylinder is made of only one material.

I wish I had my camera when the "sleeves" were installed, it was quite an interesting process. I'll take pictures tomorrow so you can see the finished result.

EDIT: Here are the comparison pics:

Stock:



My sleeves:



The pic pretty much says it all.