Thread: Properly sleeve a SR20 block

Yes the darton sleeves require removal of the material between the sleeves. There is a slit/open area even on a stock block between the sleeves so it really doesnt matter. What killed yours is the little material left on that sleeve. The Darton and AEBS sleeves can take a 92 bore without issues and still have plenty of material left to handle good power without cracking.


This is my Mazworx Darton sleeved and stepped deck block. Thing is indestructable. And the block was only 1300 shipped. I sent them a cleaned and ready block, i didnt need all the other crap such as the cleaning, line hone, and oil passage and plug R&R and cleaning. I also had the block drilled for 1/2" studs as well

Ashton why does it look like the sleeves on that block are joined between the cylinders? Or is the line still there between them?

I like that stepped deck idea. Just hope my block can be re-sleeved without issues. i.e. pressing out the existing sleeves.

That's certainly what doesn't look right about yours. Every sleeved SR that I've ever seen looks like ashton's. I almost want to say that they are either the wrong sleeves or some creative modifications were done.

There is still a line there but the sleeves butt up against each other side by side to where you cant see it unless you look close. So not only is the sleeve supported by the block but also supported against each sleeve. Again a much much better design than the sleeves you use. I would definitely go Darton if you have someone that can do the job which it appears so, you just need to have the better sleeves installed. I hope your machinist uses a torque plate during the install and final bore and hone as well. This keeps the sleeves from lifting during the final bore/hone process.

Might want to check into it. If not I would definitely just pony up the money and have mazworx do a block for you. Again you shouldnt need to do all the small stuff. Just have the basic sleeve job done with your final bore/hone picked out. Use main bolts and not studs so you dont have to line bore the bottom end, dont opt for the cleaning, just clean the block yourself as well as cleaning out the oil passages. Really no big deal.