Hey, my friend and I are looking at buying an 04-05 WRX for him. I own an 02 WRX COBB stage 2 tuned. He has gone for rides and driven my car before, and we both agree we want to get more out of his car. He has owned and driven with 300whp before so this goal is not unreasonable or out of nowhere. Eventually I would like to hit somewhere around that mark with my car as well. Here are our questions-
1)we are having a hard time finding any cars with low mileage! We are strongly considering doing a full build just to start out with low mileage. We are wondering if this is a good/bad idea and why? We are planning on doing a big turbo, fmic, etc. so maybe a build would be smart/necessary to hit 300whp and high boost as it is? You tell us!
2)outside of pistons, rods, bigger injectors, and fuel pump, what would we have to replace in the engine for a full (and safe) engine build? Also what parts (if any) other than up pipe, down pipe, headers, exhaust, turbo, fmic, ewg, boost controller, intake, and engine components would we need to upgrade to reach this goal?
3)how much can we expect this complete build to cost? We plan on installing any parts we are able to ourselves, but include in that cost estimate installation of the parts we can't do ourselves, a protune, and whatever else we are forgetting to mention. Thanks!
zax build thread is great for info so def look into that! But I will try to help you out as much as i can off of the top of my head. First off, when buying an older car such as the 04-05 wrx, it will be hard to find one with some-what low miles. But they are out there, just keep searching. The very first piece of advise i would give once you buy a car, say an 05 wrx with like 70k miles on it. Sure the miles are low for the year, but with the car almost being 10 years old, you or your friend need to make sure all of the maintenance is up to par. Timing belt would be the first thing id check, even though the milage doesnt call for it, the age of the car would. I would start there and then change all fluids; oil, coolant, power steering, transmission. Once the car is up to speed on maintenance the very next thing you should do is a leak down test, make sure the engine is healthy enough for performance mods. For 300whp, a huge turbo and a built engine isnt really needed. Now if he/you have future goals for more than that, then i would start weighing in that option. So lets move on to your list.
1-(already kind of answered the question about milage) But, you need to do more research on hitting the 300whp mark in that year wrx. A big turbo and a fmic are not needed to get there. I belive for the 04-05 the vf39 turbo is a direct replacement. (someone correct me if im wrong there) But a vf39 and an upgraded tmic would be the way to go.
2-Onto the parts you will need to reach your goal. Throw out the engine build unless you are wanting to hit 350+ whp or if your stock engine needs rebuilt due to issues already existing, then you might as well go ahead and build it. So Ill make up a mod list of what you should be looking for.
-vf39 turbo
-upgraded tmic (process west, perrin to name a couple)
-750cc-850cc injectors
-255lph fuel pump
-electronic boost control solenoid (grimmspeed, perrin make good ones)
-turbo-back exhaust
-catless uppipe(or uppipe for an external wastegate) If you go that route i would get the tial 38mm wastegate and the grimmspeed internal wastegate bracket to close your internal wastegate without having to weld it shut.
-equal length exhaust manifold
-CAI
-turbo inlet
-tgv deletes
-engine management (at these mods though, you will need a pro-tune)
3-Price is depending on if you buy some used and some new parts or all new parts. I would say 3.5-4.5k approximate.
I would go a bit larger than a VF39 for 300whp. Keep in mind EJ205 heads do not flow as much air as EJ25x heads stock for stock. You'll have to flow a bit more air on the EJ205 to hit 300whp compared to the EJ25x. I'd say a Blouch 16GXT is your best bet for 300whp. Not saying that a VF39 cannot hit 300whp, but you'll need just about every bolt-on to get there.
Of course all this is contingent on the dyno and correction factor used. I can make a stock WRX read 300whp if I wanted.
I agree with you there, the blouch 16g turbo would be far more capable. I was assuming that money was an issue, in which case a used vf39 can be had for a fraction of the cost of a new 16g. If he has a couple grand laying around to throw at a turbo, then the 16x would be be the way to go.
I concur with what has been said. Sounds the same as what I was reading back when I was considering this goal. I decided differently and went stage 2 and stayed there.