97 GT rebuild

[Legacy_2.5GT]

I've got a 97 Legacy with an EJ25. I have the motor torn apart and I was toying with the thought of boring the block and porting the heads but I cannot find anywhere with oversized pistons for it. Also I have aggresive street cams for it but I need upgrade head parts in order to use them...which needless to say I can't find either. I also heard that there was a problem with the head gaskets of this 1st generation block that caused them to prematurely fail. Can I use gaskets of a newer 2.5 to solve this problem? Any suggestion of where to find internal parts for this motor or other mods I can do to bump it up without going forced induction would be greatly appreciated. I was dealing with a company out of my home town in Canada when I bought the cams but they went out of business.

[tris91ricer]

Weisco would have your pistons for overbore.
. . .but they aint cheap.

[Matt Monson]

TWE
Cobb
Rallitek

They all make 100mm oversize pistons. They can also supply any related components you need like valve springs or bearings, etc. But personally I wouldn't spend that kind of money on that piece of crap engine!

#1 your block is phase I, and under high performance, high stress conditions, the crank will walk and the bearings will blow

#2 your heads are early Ej25 heads and have HLA's for lash adjustment. Again, not suited to high performance applications and can't safely rev past 7000 rpm. And they warp really easily. If you blew your head gasket, you probably have warped heads.

As for the head gasket, you cannot use the later head gasket on the earlier engine. It is too thin. They did rework the phase I gaskets, but really the problem lies in the combination of heads and block.

Save your money, find a good used '99 DOHC EJ25. It will have a phase II bottom end and shim under bucket DOHC heads. Much better starting place for a build. If you are going to sink $3000-4000 into a serious EJ25 build, best to spend another $800 and start with the right components...

Oh, and what are you gonna do for EM? That kind of build pretty much requires it. Sure, it will run but without tuning and a raised redline, you are going to be missing out on 15-20% of the performance potential that you have built...