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Old 09-14-2018, 05:45 PM   #1
TampaWRX
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2018 Beloved Bugeye+
Formerly WRB, now ISM

Default Safe, quiet and clean ~350hp?

Oops, forgot - we're talking about a 2018 STi!

I've been there, done that with loud, proud and obnoxious. Had a '02 bugeye with many, many mods until a year ago today. I'm old now and I would strongly prefer to be making decent power without dealing with the drone, BOV squeals and loads of NVH that come with aggressively modifying a Scooby. I would also like to keep my emissions hardware fully intact and functional. Ideally, any mods would make the car more effectively suck, bang and blow, so I would love to hear we can meet or beat the OEM mpg. Am I suffering early onset dementia? Can we get a little more than 45bhp out of the ancient, awful, horrible EJ257 without swapping everything but the longblock*?

I did several searches and nothing came back answering my question. If I missed something, please post a link and let's lock this thread.



* /s I love a semi-closed deck, reliable engine with plenty of forged components and a long history of making more than adequate power
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Last edited by TampaWRX; 09-14-2018 at 09:08 PM.
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Old 09-14-2018, 06:23 PM   #2
dryvby
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The sixes sound like porsches if you squint hard enough. 3.6 and an ecu tuned exhaust cant be beat. Ill be doing that as im aging on too...
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Old 09-14-2018, 06:54 PM   #3
Stretch18
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pandiculation

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What car are we talking about?

The things that make our cars droney and loud have next to nothing to do with power. Keep the stock intake and catback and stay IWG and the other power adders don’t make much noise.
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Old 09-14-2018, 08:53 PM   #4
Gr33ntumb
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Varex muffler and close the valve
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Old 09-15-2018, 03:40 PM   #5
bp05obxt
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Default Safe, quiet and clean ~350hp?

Quote:
Originally Posted by Gr33ntumb View Post
Varex muffler and close the valve


Really are awesome. Put one on an 02 wrx and it was super convenient. Loud and proud until it needed to be quiet as a mouse.


350whp (mustang Dyno) on a stock block would be doable with a bigger turbo, but either way it is borrowed time on the life of the pistons. They just break eventually.
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Old 09-15-2018, 08:25 PM   #6
mrsaturn7085
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315 whp is doable on the single AVCS EJ257 at stock boost with nothing more than intake and exhaust parts and good tuning.

You goal is completely reasonable but if you shoot for 325-335 whp and don't get hung up on 350 being a magic number, you'll have a much easier go at it.
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Old 09-16-2018, 06:54 AM   #7
Turpid Porpoise
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My 2008 STI has led its whole life(75k miles) in the 315-330 whp range so I’d agree that if you lower our expectations a hair you’re probably safe but it all comes down to the tune and a bit of luck.
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Old 09-17-2018, 01:56 PM   #8
Zcypot
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Quote:
Originally Posted by TampaWRX View Post
Oops, forgot - we're talking about a 2018 STi!

I've been there, done that with loud, proud and obnoxious. Had a '02 bugeye with many, many mods until a year ago today. I'm old now and I would strongly prefer to be making decent power without dealing with the drone, BOV squeals and loads of NVH that come with aggressively modifying a Scooby. I would also like to keep my emissions hardware fully intact and functional. Ideally, any mods would make the car more effectively suck, bang and blow, so I would love to hear we can meet or beat the OEM mpg. Am I suffering early onset dementia? Can we get a little more than 45bhp out of the ancient, awful, horrible EJ257 without swapping everything but the longblock*?

I did several searches and nothing came back answering my question. If I missed something, please post a link and let's lock this thread.



* /s I love a semi-closed deck, reliable engine with plenty of forged components and a long history of making more than adequate power
you are talking about the 2018 right??

I was running 367/400 on E85 on my WRX with just bolt ons and stock turbo, it can be done. For pump gas you'll definitely need a larger turbo if you have no E85 available near you. When it comes down to it, everything breaks when you race it.
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Old 09-17-2018, 04:04 PM   #9
DEANORS
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I would recommend looking at fueling upgrades and a flex fuel tune/setup.
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Old 09-17-2018, 10:11 PM   #10
Scorpius
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Stock exhaust, DP, fuel pump/injectors, Protune. Enjoy.
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Old 09-18-2018, 12:08 AM   #11
NSFW
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350 crank horsepower, Dynojet wheel horsepower, or Mustang wheel horsepower?

I got 377whp with an ATP GT3076, catted downpipe, 3" Perrin resonated midpipe and stock mufflers on my 05 LGT. Just pump gas, no water/meth. I think it was a Dynocom dyno (not sure, it was several yeares ago) and it read about like a Dynojet.

The newer GTX3071 makes similar power (but comes on at lower RPM), so I guess for 350whp, a GTX3067 from ATP or KillerB would probably be about right. I think... search for GTX 3067 just to be sure I'm not off my rocker.
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Old 09-18-2018, 05:30 PM   #12
MikeG4936
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Injectors, fuel pump, and E85 will get you close enough on a stock turbo/longblock. It's a really fun setup for the street.
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Old 09-18-2018, 05:59 PM   #13
bp05obxt
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Quote:
Originally Posted by MikeG4936 View Post
Injectors, fuel pump, and E85 will get you close enough on a stock turbo/longblock. It's a really fun setup for the street.


Until it breaks but seriously they all do eventually
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Old 09-19-2018, 01:28 AM   #14
mrsaturn7085
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Quote:
Originally Posted by bp05obxt View Post
Until it breaks but seriously they all do eventually
Injectors, pump, E85, a good tune, and regular maintenance should last... basically forever @ 350 whp. Just don't forget that last one and don't drive it like a moron.
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Old 09-19-2018, 05:24 PM   #15
zugu
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340whp 370wtq on E75.
2013 WRX, 22psi, 20k miles.

It's a great DD setup.
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Old 01-12-2019, 03:21 PM   #16
TampaWRX
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Formerly WRB, now ISM

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Life got in the way and I forgot to come back and thank everyone for your replies to this one. I'm all about adjusting expectations if it means safe, quiet power. I like the idea of minor tweaks a good tune. Thanks all!
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