i have an 03 wrx and i am looking to bump up the power and take it to the next level with a different block. i dont want to spend too much but i know i will have to spend some. i have a perfectly healthy wrx 2.0 running a stage 4 setup with a gt30-10. putting 316 wheel horse power and 292 ft lbs or torque. i drove my friends vf22 sti and boy there is so much torque in the sti it made me jealous. he layed down 377 torque on a dyno on a vf22. i gess i want the best of bost worlds.i love the power of the sti 2.5 but i love the gearing of the wrx. i want to be able to run 28-30 psi on whatever block i get. if i get a 2.5 usdm block i will get forged pistons. also thinking about going closed deck but just unsure about the torque verses the smaller diaplacement motor. i will be using my stock wrx heads but will get them reworked and ported and maybe some sti cams. so what is stronger

a. 2.2t with wrx heads fully forged @30psi

b. 2.5usdm sti motor fully forged @30ps

i want lots of torque i will be also running a slowboy gt13 ball bearing turbo with which ever motor. help me choose thanx

both using wrx heads with a valve job ported and polished and sti cams.

my wrx shortblock only has 12k miles on it but looking to do hte swap soon. whaty do these wrx blocks sell for anyway.

 

you can also get a bored over 2.2 from axis power. They have an option for 2.36. Another option to look at.

 

The Slowboy GT30-13 on a 2.5 liter motor only needs about 23-24 psi to be happy. A friend of mine just made 337 whp on a GT30-12 at Subaru Specialists. In fact, Slowboy gave him their contingency prize for making power on that turbo.

 

I was told by a tuner near me that a sti 2.5 block with wrx heads can't boost over 16 psi with out blowing up. I may have misunderstood but he said its cause the bore size of the cylinder being to big for the combustion chamber on the head (if that makes sense) and if you use a think head gasket it will help. why couldn't you just port the combustion chamber to match the cylinder? and he said the only way to boost more than 16 is to use the single cam sti heads then you can boost what ever you want. is there any truth to this? also i may have misunderstood the guy

sorry for hijacking but it seemed like a good place to ask

Thanks,
Nathan

 

Im new here but im on some other forums and I just finished my 2.5 swap in my bugeye.
I got the s2 package and im in the break in peroid still. I made 300 whp at 18 psi on the gt30-12 but the powerband sucked on the 2.0 wrx motor.
now that I have the bigger block im thinking about selling my turbo and getting the CP32 kit. comes with up, dp and gt32 twinscroll turbo. I got a ride in a bugeye with a 2.65 block and gt32 and it felt like an STi but with lots more power. great pick up and awesome power.
I say go with the 2.5 and get something like a gt30 or the 32. you wont be dissapointed.

 

Actually the stock wrx heads are a far better design than the sti, sti heads just create a headache bc of the variable valve timing. your setup is just like the one im saving up for im getting a built motor by tech works engineering (the ONLY subaru specialists) all u need is to get their wrx blueprinted heads w their cams and ull notice a huge diff, or if u want to save a lil dough just get the cams bc the stock heads are fine the way they are. oh and get it tuned by a REPUTABLE tuner. My friend just went through a huge ordeal bc he took his car to Forced Inductions Systems (FIS) here in dallas and they tuned it horribly (and blew his random technology cats)!!! Talk to any good tuner and they will all tell u that just doing a few dyno pulls and adjusting a few numbers on ur ecu just to make peak hp is only a small part of a good tuning job. If u dont already have the gt30 or 32 (32 is what all the co.s are using now) get the kit from gp moto bc its an excelent kit that includes everything u need from the intercooler to injectors and it comes with a map to make ur life easier. hope this long rant helps

 

if you really want torque, check out Crawford's R4 2.8L STi block

 

I am really interested in picking up the Axis racing 2.5L shortblock, not too sure how it will work with WRX heads, but I am going to try. I read here that the WRX heads are bad with a STI block, and on NASIOC that the WRX heads are better for a shortblock upgrade due to the lack of all of the VVT stuff. I am not too sure which is right, I will consult a reputable shop and post again.