Rebuild SR20DE with overbore pistons

SR20DEviant · Sep 3rd, 2003, 02:01 PM

I'm thinking of building up a DE short block with overbore high compression pistons. Anyone ever done this or know someone who has? My idea involves using stock Nissan bearings and thrust washers, ARP rod bolts, ARP head studs, and Wiseco 12:1 88mm pistons and the rings they come with. Would 12:1 be unsafe on 93 octane pump gas? How big can you go over the stock 86mm piston? I plan on using my stock JDM lo port set up and JDM header too. As well as the stock cams and head. Im really just looking for more compression to increase power throughout the RPM range. But I figure, if Im going to get high comp. pistons, why not go oversize, right? What kind of tq. and hp. gain do you guys think I should see?

BORNGEARHEAD · Sep 3rd, 2003, 09:54 PM

With that comression you will be on race gas. I am looking at doing 12.5:1 compression and race gas is mandatory.

Andreas Miko · Sep 5th, 2003, 06:44 AM

It will be cheaper to get a VE motor and you will make more WHP.

If you get a VE motor you can get 190 WHP with VE motor $2000, Fujitsubo header $600, 2.5 in exhaust $450 , JWT Pop filter $125 and JWT comp $550. With the VE motor parts are coming as we speak to make a goal of 210 WHP with bolt ons.

If you do a DE build up of your motor The most you will get is 175-180 WHP with a very rough idle. Cost of ARP head studs $250, Pistons $600, reboring block $100, HS Headers $450, 2.5 inch Exhasut $450, JWT Pop Filter $125, Ported head $800, Head gasket for larger pistons $150, JWT Comp $550, C3 cams $550, Valve springs and retainers $500. With the DE build up thats it no more gains.

SR20DEviant · Sep 5th, 2003, 09:46 PM

Thanks. Of course, I have considered the VE swap but I just wanted higher compression in my DE. I will probably do the VE swap ultimately in the future. I am in an engine rebuild class and thought it would be a good project to do in the shop at school.

wickedsr20 · Sep 6th, 2003, 11:00 PM

Those that do this usually go 1 mm larger (87 mm) than stock. Best example that comes to mind is the Disco Potato Sentra. It was built up with a 1 mm overbore and beefed up internals before it's turbo install.