I have a 98 rs and would like to install sti internals. I was wondering if a phase 1 crankshaft will accept sti rods and pistons? If not does anyone know of a good set of rods and pistons and rods that are reasonbly priced? Where or who would you get them from? What turbo would you use? I'm going to use a front mount intercooler and flippin the intake. Its going to be a daily driver when done so I would like to keep the power at the wheels between275-350. Any suggestions with engine managemnet? I have heard that the e-manage ultimate is a good option. Any suggestions would be great this is my first subbie build. I have allready ported and polished the heads and installed delta cams when I did head gaskets. Thanks for all your help!
350-400 on a DD? Good luck keeping it reliable. Also are you looking to be able to tune it yourself or having someone tune it? Cause another option is Hydra EMS
I'm gonna be the first one to say it, but search. This has been hashed out many times over lots of forums. nasioc, rs25, sl-i, bbs, etc. First things first. Take that N/A 2.5 block and put it in the corner for a spare. They really aren't woth building so much. The open deck and naturally aspirated nature of the motor doesn't lend itself to hold up to much power, especially if 350-400 whp is your goal. Not a chance. Save the heads for a stronger bottom end, as your DOHC 2.5 heads flow very well. Get yourself an EJ22T block or EJ257 and be done with it. Eagle rods in the 22T and some sort of forged pistons and you're golden. Toss some Mahle's in a 257 and you're also set. As for a turbo, a GT3076 is a pretty good option for that power range. I recommend the .78 twinscroll housing and an appropriate exhaust manifold. And one more time, search search search. There's sooooo much info out there.
I have a 2.5NA motor... I'm able to get 220whp/265wtq. But i'm scared to push it anymore. I have 10psi with great timing and tuning.
i'm sorry guys i was hoping for 300 at the wheels. Itried to search but I think there is nothing better then the words right from the pros themselves!!
I wouldn't say we're pros, but some of us have quite a bit of wrench time into these things. What I was getting at is if you are going into the bottom end of the motor, get yourself a turbo block to start with, and go from there. Brian if proof that you can make decent power on the stock block, but you are running the ragged edge of what that motor is capable of holding. And that all depends on tuning.
so i agree with that i should use a turbo lower end but at that point i may as well swap the entire engine in it. iam a mechanic so i really would like to do this but i am no tuning expert. i would love to drop a sti block in and use my top end but im not sure on what management should be used. so many people have there managemnt listed as the best but i really would like to know what is the easiest to use as well as the safest one for the motor.
Sometimes, starting with a fresh, OEM block is the best way to go. You start frankensteining motor parts together and you don't know what you'll end up with. THat isn't a spot you want to be in as a first timer. If you can find an EJ257 new, that's great. A full STi engine/ECU (don't need the tranny really) would be better. The ECU tuning and hardware you choose is only as safe as the tune that is flashed to it. You could get the Hydra, which is arguably one of the best and most feature rich units for the Subaru, but if your tune is crap and the parameters are entered in by a mad ape, you're gonna pop your block. Same goes for the UTEC, not as sophisticated, but with a really good tune, you'll be fine. Your best bet would be to plan your engine and power bits with a goal in mind, be it max power, powerband, or whatever. Plan what parts you want to use, and do some research into other people's builds (go to Nasioc, if you want to do it, it has likely been done to death by someone else). Then, when you have a plan in mind, contact a trusted tuner and ask them what they recommend for your particular setup. And it doesn't hurt asking them during the build for advice on parts to use and things to do.
