I have been trying to do some research. I currently have a 2019 STI. Trading it in for 2021, been waiting 2 months already and won't arrive for another month.
I really enjoy the platform and am always surprised at stock numbers and how it feels (maybe some will disagree). But I have some plans for the new one when it arrives, and somewhere down the road, I plan on doing a complete build and aiming for a fun 550WHP reliable (I hope) street vehicle. I have driven the Cadillac CTS-V and it was really fun/rush to drive, I expect this build would be very different. Not really interested in the track, but who's to say that may change.
Anyways, my question is if anyone has achieved 550WHP reliably on this platform? I am trying to figure out cost wise what this may be to get here. I think having a built car would be super cool and if anyone is a true car person, they would definitely appreciate it. I would love to share the fun with people and I would say that is my goal. To get smiles per gallon
I appreciate any feedback!
Like others have said, reliable at that power level is relative. I daily 560whp, and besides the cost, there are a few other things to keep in mind. I'm not trying to be condescending, but a CTSV is nothing like a 700+hp STI. The tree you inevitably understeer into comes up quick at that power level. Second, depending on your cam, turbo, and clutch set up, they can be a pain to daily. Lastly, maintenance will happen more often, and be more expensive. Oil change intervals with ethanol are shorter, and depending on what oil you run, more expensive. Brakes, tires, trans fluid, clutches head gaskets even. Gas will also be an issue if you cant find E85, or only have 91. All that said, it can be done "reliably" for around 20-30k, give or take how far you want to take it, and if you want more power later. Which you will. Buy once, cry once.
-You're looking at a forged bottom end, rods, pistons, bearings, closed decking, or sleeves, pinned mains(if you want), beefed up hardware etc. There are a few companies that sell assembled short/ long blocks. Over build your motor. If you're doing the work yourself, read, a lot, about everything.
-You can make 500 with stock heads, but if you're pulling the motor and building the short block, build the heads. You don't need to worry about the valves, but the springs, retainers, guides , I would greatly consider, especially if you're going to be upping the rpms. As for cams, I run kelford 264/260's. Its a good street cam. But I've seen builds make 500+ on stock cams. You do not need to port your heads, but again, if your building them, and the moneys right, might not be a bad idea.
-JE pro seal head gaskets wouldn't hurt. I run an Athena Gasket with fire rings.
-Consider 14mm headstuds. At the very least a set of 625 studs. Regardless of the turbo you run, you'll be over 25psi, and lifting the head becomes a possibility.
-Fueling will need to be addressed. Bigger pump, fuel rails, injectors, regulator, filter. E85 will be a must, unless your are running a lot of boost and are being pretty aggressive with the timing. IMO over build your fuel system. Never a bad idea.
-The stock intake manifold will be good, but you'll need a set of TGV deletes. Id also consider a front mount intercooler, external wastegate set up, 3-4 port boost control solenoid. There are a few turbos that will make it to 550 in stock location, but do a rotated turbo set up. Just saying. 3in exhaust. equal length headers.
-If you want a heightened sense of security, you can go with a stand alone ECU, which has far more capabilities when implementing failsafe's.
-Get an Air Oil separator. The stock PCV system is a problem. An oil cooler might not be a bad idea, depending on where you live, or if you want to track the car. Oil pickup is a must. Ask your engine guy about a bigger oil pump. Some suggest it, some think its unnecessary for street cars.
-I HIGHLY suggest you get a twin disc clutch that is geared towards street use. Puck clutches are no good for a daily. My opinion.
-Beefed up mounts. Group N mounts will do for a daily. Fluid dampener and pulley tensioner are pretty inexpensive, all things considered.
-You're going to need, at the very least, a 3bar MAP sensor.
- Do your research on what turbo you wanna run. The bigger, the more laggy, the less boost you'll need to make your number. the smaller, more responsive, the more boost you'll need. There are countless forums on turbos set ups. I can only tell you what I've ran. An FP Black will get you there with a walbro 450, 1300cc injectors, at @26ish lbs on E85 stock location, or a PTE 6466. At the end of the day, ask the guys building your car, and your tuner. They will no better than anyone.
I'm sure I've missed some things, but these are definitely things you will need to take into consideration when trying to turn a 30k car into a 60k car.