Hey i wanted to know if i can just drop forged pistons in my current block and be done with it. I dont want to buy a new short block. Is it okay to use my current block and just add pistons too it.

Yep, perfectly fine.

it is perfectly fine if you bore,or hone the block. it also depends on how many miles,and if anything was going on. i really would not just drop in forged pistons unless it was in a brand spanking new motor.i am talking about oem size pistons also :)

I even wouldn't want to drop forged pistons in a new block. OEM clearance is .0004 IIRC, typical low silicon forged pistons need ~.002 clearance. You would still have to hone the block.

I even wouldn't want to drop forged pistons in a new block. OEM clearance is .0004 IIRC, typical low silicon forged pistons need ~.002 clearance. You would still have to hone the block.

they do it everyday with no problems. checkout cp,wiesco , ross ,and all the other companies that make forged pistons.on a brand new unused block they make standard bore pistons. they are made with clearance in mind. :)

I guess no one's read "How to Build a Motor". Chapter 1: You measure things. Then you measure them again.

Dropping in forged pistons works well sometimes...but if you get a smoke bomb you'll be regretting your choice not to have the pistons installed properly. If you don't want to believe me--just call your local machine shop and ask them if they measure their piston-to-bore tolerances or just drop them in. Piston tolerances can be off. Subaru's tolerances can be off.

I can't speak to how to go about ensuring all of your tolerances and measurements are good...since I didn't, but so far my engine is fine.

However, if you've never swapped pistons before, I'd recommend against it. If you are a novice but still decide to do it, just take care and take your time. Almost all the information you'd need you can find on here. I've got a solid short-list of folks on here who've helped me through pm or on the phone who are very smart and reliable.

However, even though I don't have any experience with checking tolerances and freshening the cylinder walls, etc.., the reason I swapped my pistons with forged (vs. oem) was for insurance, ie. an extra measure to protect against the engine breaking again. Knowing that, freshening the block and measuring everything is insurance as well and now I scratch my head as to why I didn't do it.

I guess no one's read "How to Build a Motor". Chapter 1: You measure things. Then you measure them again.

Dropping in forged pistons works well sometimes...but if you get a smoke bomb you'll be regretting your choice not to have the pistons installed properly. If you don't want to believe me--just call your local machine shop and ask them if they measure their piston-to-bore tolerances or just drop them in. Piston tolerances can be off. Subaru's tolerances can be off.

worldone has a shop install them for them,and they seem to have no problems.i am sure they are put to spec. all i am saying is most piston makers make a std bore forged piston,and by theroy they should drop right in. me i am anal enough to second guess anything unless i do it myself.

im gonna have andrew tech automotive do it.

also do i need to get forged pistons or are the stock ones fine. I have 10.7k miles on my engine.

also do i need to get forged pistons or are the stock ones fine. I have 10.7k miles on my engine.What are your plans for the car?

based on my recent experience with crawford, anyone who just drops in forged pistons or lets a manufacturer do so is making a huge mistake that can cost you thousands of dollars and months of down time. do it right or don't do it.

Just an FYI from my experience and some others, Forged pistons will also consume more oil especially in the beginning. I would keep a careful eye on my oil no matter what you do. I also agree with MeetMrGlock, you can't just drop them in or your going to have problems later.

im gonna have andrew tech automotive do it.
Same here.

What are your plans for the car?

Ultimate Racing GT35R or a Custom T04R setup. Im trying to make 420-430awhp on 93 pump and 500+awhp on 93+meth injection. Also what do you guys mean you cant just drop in forged pistons. If there are other things that need to be done ill do it. Andrewtech automotive is perhaps the best shop in the MAIC area.