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$Cost to make reliable 400 whp 2017 STI?

109386 Views 53 Replies 14 Participants Last post by  XJman
I'm thinking about buying a new 2017 STI. I'd really like it to make more power but would not want to have to worry about something going wrong since the warranty will obviously be compromised. So if I wanted 400 wheel horsepower or more what's the best safest route and how much would it cost?

I know all the basic parts evolved when tuning these cars for more power. But I want reliable power. So aside from all the bolt-ons like downpipe, upgraded fuel pump, exhaust, injectors, blah blah blah etc etc.

For reliability would it be necessary for forged pistons and a closed deck block? Or would the pistons be good enough? And what would the typical cost be for 400hp? I know for 300hp to the wheels stage 2 it's about $2900..
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Northern Kentucky. They are all over the roads around here.
I was thinking they’re all cubed at this point. I haven’t seen a Lancer or a Chrysler in many months, even though I am in SoCal where people are car crazy. I think the Evo/SRT party is over.
Thats really surprising. The srt4 is becoming more of a rarity, and even rarer to find one with solid body work,, but I still see evo 8s and 9s frequently. Not so much the X, I think people are hoarding them because they think every one will be a unique collectors edition price in a few years.

Maybe a regional thing? Awd makes nice in areas where snow and ice are common in the winter maybe they just migrated this way
Pick whether you want to be Ridetillidie or Cole F. and let me know. I'll close the other account.
I'm nearly confident he has another one too. I've seen roughly this same post before. I won't ban him because I want to see how his $75k dollar shitbox feels when he is still getting his doors sucked off by civics with a turbo and how he feels spending that 10k again in 5000 miles when that iag block is toast.
We’ll I did 409 whp on e60 with
Cobb AOS 520$
Invidia catback R400 1100$
Invidia catless downpipe (discontinued) 180$
Cobb flex fuel 300$
Aem 340 fuel pump 150$
Nostrum high pressure pump 900$
IBR egr delete 40$
Turbo xs tgv delete 50$
Stx 71 turbo swap 700$
K and N typhoon CAI 200$
Perrin turbo inlet hose 100$
Grimm speed bcm 200$
Mishimoto radiator 200$
Mishimoto tmic 1000$
900$ dual tune from TPG
Yes it’s not cheap. Yes it is safe too make the 400whp also but only on corn. I wouldn’t do it any other way
A lot of my parts were 2nd hand I bought off a part out. The guy said he’d rather have a old vette. He made 411hp with this same turbo and beat 500hp mustangs. Bare in mind, I’m not even in a sti.
I’m in a wrx premium. I don’t remember exact numbers on parts but it was around this estimate.
About 6500 on a stock 2016 wrx. If you do all the work you’re self except the tune. Expect you’re car too sit awhile.
Stock block? Good luck
It’s completely fine on corn.
Again dual map so it’s swappable.
you gotta read into it.
A lot of people run it reliably but i kept the reliability in mind
With a stock block at 400whp.

Boy I've read some silly things, this might be the best yet. Unless you only put around that's one rip away from a 10k dollar rebuild.

Cheap, powerful, reliable. Pick two.

You have cheap, and you have powerful.
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