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Does anyone here have a 2015+ build that makes reliably ~550WHP?

11K views 40 replies 17 participants last post by  Karlot 
#1 ·
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!
 
#2 ·
This is a subjective answer, but you're best bet is to get a built motor from IAG or similar reputable engine builder, and go from there. You'll need to spend some money to properly build with the right parts and systems (like oiling/cooling, etc.) I'd say expect to pay somewhere between 20-30k for a solid "reliable" build. There are others on here who will be a better resource than me, but I can tell you right now that it's always better to buy higher quality, more expensive parts rather than cheaping out and risk breaking something. There are numerous turbos that can get you that power, a few would be Forced Performance (FP Black), Precision Turbo, and Garrett. I'd suggest going to YouTube or looking on this forum for builds that are around your desired horsepower goals. The great thing about the EJ257 is that it's been around for so long, and there are proven methods to reaching any kind of power range. Your tuner will also be instrumental in getting the most reliability out of the engine. Since you're already an owner of a 2019, you probably know that driving habits also contribute to the longevity of these engines. Simple answer: E85, big turbo.
 
#3 ·
Longblock and engine hardware alone you should expect to spend north of 10-15k.
That includes internals (built block), fmic, dp, turbo, injectors, rails, etc. etc.
Then you wana power-proof the chassis with mounts, suspension, brake improvements (pads and lines), etc.
Don't forget about oiling and cooling improvements either.
Then you gotta put some wide GOOD rubber under the chassis.
I see so many people quick to shove 265's under their car but a good set of 245's would likely outperform them.
I'd say expect to spend at least 25 to get it to where it's at that power level reliably.
Of course, a lot of the cost can/ will depend on what you install yourself.
If you just wana throw money at a shop and say 'give me a super fast car', they'll do it, but then you're looking at easily north of 30 if you let them.

E85 makes a massive impact too.
You can get well north of 300 wheel on a basic stage 2 with an e85 pro-tune, but will be struggling to crack 3 with the same hardware on regular gas.

The main difference between the 2021 and a 2008 engine wise is a more efficient hot side on the turbo and slightly stronger internals. Once you go for 550hp, it all becomes the same engine, because you are basically going to be replacing everything with the same parts.

550hp reliably out of a 2.5L doesn't come cheap.
That said, you can factor the GR(2008-2014) and earlier VA(2015-2018) into your research, because the commonalities on the hardware front are pretty linear.

+1 on the IAG front. If I was going to be building my engine for power, I'd be picking up one of their built long blocks with a closed deck, no question.
 
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#5 ·
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!
I apologize in advance for taking your posting in another direction, but I had a question regarding the delivery of your vehicle. When did you order your car and how do you know you have a month left until it arrives? I ordered my STI limited at the beginning of June and my salesman texted me a few days ago saying it looks like it will be arriving mid-July. I’m curious, how do you know when it will arrive? Thanks!
 
#6 ·
Look into Prime Motoring and JR Tuned. They supposedly have a few in the 500-610 whp range on stock 19 up long blocks. The are all rotated turbo setups on E85. I guy I follow on Instagram has 16-17k miles on the 610 whp build. I would not say these are going to hit 50k plus miles at that hp level, but who knows. fyi
 
#7 ·
it's easy to do, but expensive. to make that power reliably you'll want:
IAG Block: go closed deck for sure.
IAG Heads: go with the bigger head studs and a small to medium sized cam for the street.
a clutch that will hold this wtq you'll make
all associated gaskets needed
turbo, for this, go rotated, you will have a better hotside which will allow for better spool up and response times. you can make 550+ on multiple different turbos. personally i say the smaller the better just cause the smaller it is the more responsive it'll be. you also have twinscroll options which will jack up the price, although that is not necessary by any means. a single scroll setup will be perfectly good.
fuel system. for this i'd HIGHLY suggest going with e85. making that much power on pump gas is possible, but will be so laggy to get a turbo big enough to flow that much it really wont be all that fun. flex fuel aka e85 is not only better for making power, but is safer than pump gas as it is less prone to detonation.
supporting mods, cat back, sensors, etc.
reliability mods, aos, cyl 4 cooling mod, etc.


all in all i'd guess you'll sit about 18-20k in parts alone. maybe a tad more. if you can do the labor yourself, wonderful, if not i'd bump that up into the 30k ish range for everything.

all this said, i have seen people making over 500 on the stock long block on the newer models. while this may be possible i'm not sure how reliable it would be. if you want to go this route expect to have to get a motor at some point. also expect that you may need to get every oil line replaced and possibly rebuild the turbo if it blows, rebuilding the turbo is a worst case scenario, but a possibility. replacing the oiling system is something suggested by any engine builder if the motor was not in good running condition when pulled.
 
#8 ·
Do you know what 550 WHP feels like in a 2021 STI? I ask this because you seem to have zeroed in on an arbitrary amount of power right out of the box and I'm not sure you know why you want this much power.

The ethos around this car has always been balanced performance. The platforms perceived shortcomings are personal, and experiencing the car in moderate build/improvement increments allows you to address what YOU find lacking.
 
#9 ·
This right here ^^ To the OP, why is 550whp a goal? Not for nothing but the stock power level of these cars and 550whp is VERY different. I would first make sure you know what you're getting yourself into. Most guys dont jump from stock to a full on build. I would first suggest you try and do some baby steps in mods and see how you feel about the power output then. It may not be a good idea to spend 20-30K on a build if all you may be comfortable driving is roughly a fraction of that cost in terms of power output.
 
#11 · (Edited)
finally if you do this "right" you will no longer have a nice car. It will be an awesome toy - one that I would thoroughly enjoy for my 120 mi/day and one that my wife would not want to ride in . . .
 
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#15 ·
I'm pushing about 550ish to the wheels in my 15 sit. I started out doing full bolt ons and ethonal. Ran that for a couple years then built the motor and upgraded to heads. Running a blouch 4.0xtr on ethonal and the car moves. I made the mistake in getting the arp2000 head studs and they couldn't hold. Now I have are 625+ and getting the car back on the road. I daily the sit and by the way it drove you wouldn't guess it made that much.
 
#16 ·
I'm pushing about 550ish to the wheels in my 15 sit. . . . built the motor and upgraded to heads. Running a blouch 4.0xtr on ethonal and the car moves. I made the mistake in getting the arp2000 head studs and they couldn't hold. Now I have are 625+ and getting the car back on the road. I daily the sit and by the way it drove you wouldn't guess it made that much.
Was it reliable?
Will it be reliable?
 
#22 · (Edited)
Will you replace replace the gaskets?
 
#29 ·
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.
 
#30 ·
This is great advice. I really appreciate the response - I am doing a trade up for a 2021 currently and got an offer I couldn't refuse. This will definitely be somewhere down the line.

I think I will start small and work up. Perhaps I may run into a wall.. in the sense where maybe I'll find a power level I wouldn't want to go above. But appreciate this advice!
 
#31 · (Edited)
Yeah, the above is the cook book . . .

I want to say thought that if your are doing a build of that magnitude justice, it's not goin to be a normal street car and if you want normal, just don't do it. Even at 350+ stuff comes up fast on the street.

One thing made me sad in that post understeer. Having understeer on a car with build like that has not done it justice. It took me a long time to figure out why I've been so unimpressed with my 2020. It was that my 350+AWHP 05 is far more of a rear wheel drive car than the stock 2020. In fact I now drive the 2020 like a FWD car :(. Makes me realize I will never be impressed without more power and weight transfer - even with a cement stiff suspension . . .
 
#32 ·
Yeah, the above is the cook book . . .

I want to say thought that if your are doing a build of that magnitude justice, it's not goin to be a normal street car and if you want normal, just don't do it. Even at 350+ stuff comes up fast on the street.

One thing made me sad in that post oversteer. Having understeer on a car with build like that has not done it justice. It took me a long time to figure out why I've been so unimpressed with my 2020. It was that my 350+AWHP 05 i far more of a rear wheel drive car that the stock 2020. In fact I now drive the 2020 like a FWD car :(. Makes me realize I will never be impressed without more power and weight transfer - even with a cement stiff suspension . . .
Sounds like you, sir, need bigger swaybars :LOL:
 
#33 ·
In the 2020? Yeah, its stock. For the time being it is what it is for.

But what I was commenting on was a fully built car with stock sounding understeer. Even a mid power car like my 05 is nothing like stock. Under power becomes mostly a rear-wheel drive car. At "track" speeds it is light actually light and nimble. Under decel? Handing there is all about the driver . . . in a decent handing STI.
 
#35 ·
I don’t care how well your car is set up. If your doing 100+ on the street, which you shouldn’t , but we all have, and a corner sneaks up on you, you are not oversteering out of that. You will continue on straight with you wheel at full lock, and become a stock of celery. Respectfully. The track, that’s another story. Is a good point to bring up though. I left out suspension stuff.
 
#36 ·
I had a typo - intended and thought I typed understeer. Now corrected. Comming up fast is true regardless. - same
 
#37 ·
Nobody seems to mention they have 500+ hp for 1/2 a second at 6k-7k rpm? Its a world of difference going from a large displacement v8 with or w/o a supercharger to a small displacement 4 cylinder with a huge turbo.

Everyone seems to have the dream of FIE HUNNERT HERSPOWERS until they realize it's going to cost them 20 grand, many months if not years of time, and wind up with a car that sucks to drive everyday.

Making your subi a drag strip car? go nuts. You want big power, reliable with smooth power delivery, for the street, pick a different car =)
 
#38 ·
Seems the OP has abandoned post.

Question for some of you guys... How would you specifically say drivability is sacrificed? I ask because some posts make it seem like the car will be transformed into a play toy only, without much ability for daily life. I know this is subjective, just looking for experiences you've had that have driven the opinions.

For me, it's a subtle increase in NVH, obviously the power delivery changes, and potentially cold start anomalies on E85 (although E85 cold start tunes are much better than they used to be). Aside from that, our cars have generally drive well on the street. Not any different from stock aside from the above changes. With a little coaching to the wife and a 'do not floor it, unless you're ready for it' warning, she does her usual errands, pick up kids, etc., without issue.
 
#39 ·
I have yet to drive an STi with 500+. but i have driven a few making over 400, and i'd say the same thing. a little more NVH, but nothing crazy, and so long as you arent flooring it everywhere and driving normally, it's really not hard to do at all, i'd imagine with 500+ all it would be is a tad more lag when you step on it. even with my current setup making 377whp i have to drop a gear to get into the powerband, and i know i'm doing it, driving normally it's not like a light switch like some make it out to be.
 
#40 ·
It is always a trade off on ICE with smaller displacement. Looking for more power above 450-500 whp will generally require a turbo that does not really hit until 5k plus. If your looking for major off the bottom torque go larger displacement or electric.
 
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