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Old 11-20-2011, 11:06 PM   #51
Schister66
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With a proper tune and good maintenance, I hope 350awhp is reliable...If not, Subaru needs to do a little better job putting engines together. I know it's comparing apples to oranges, but its not uncommon to see stock 1.8L B series Hondas pushing 400whp on stock blocks...if they can do it with 2/3 the displacement and cast 10:1 or 11:1 pistons, i hope an STi can handle it.

Next winter my STi will be getting a few new toys and with ~100k on the clock, i'm looking for 380-400awhp on corn. I guess we shall see how it likes it
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Old 11-20-2011, 11:43 PM   #52
Bones Malone
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Running 304whp on my '11 sti now with a solid tune. Going to run e85 soon on stock turbo. I think it would be a TAD safer to run e85 because e85 has somewhat of a cooling effect. I want to hit 340, hopefully motor will last!
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Old 11-21-2011, 05:05 PM   #53
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Quote:
Originally Posted by Schister66 View Post
With a proper tune and good maintenance, I hope 350awhp is reliable...If not, Subaru needs to do a little better job putting engines together. I know it's comparing apples to oranges, but its not uncommon to see stock 1.8L B series Hondas pushing 400whp on stock blocks...if they can do it with 2/3 the displacement and cast 10:1 or 11:1 pistons, i hope an STi can handle it.

Next winter my STi will be getting a few new toys and with ~100k on the clock, i'm looking for 380-400awhp on corn. I guess we shall see how it likes it
LOL. Good luck.
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Old 11-21-2011, 05:20 PM   #54
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Quote:
Originally Posted by 04furesterXT View Post
LOL. Good luck.
Thanks, but i doubt very much I will be needing it. Furthermore, if it can't handle it in stock form, its a pathetic car and will be moving down the line.

A stock STi makes roughly 240awhp...to ask 380awhp of it is about 160% of its intended stress/power. For comparison's sake, my turbo GSR made 364whp on the stock block whereas a stock non-turbo makes roughly 160whp. That's more than double and still nowhere near pushing it to the limit. Several of my friends have run into the 400whp range with nothing more than a stock B series Honda, E85 and a turbo setup. It isn't rocket science provided the OEM parts are quality and your tuner is competent.

Ive been building turbo Hondas for the past 5 years so it isn't my first time around the block, but I suppose not everything will translate directly from one manufacturer to the next. I guess we'll see how things turn out. For the record, my buddy Jon's 04 STi (with nearly 100k miles) is at 421awhp/420wtq with nothing more than a MAP 20G, E85 and a few simple bolt ons...there's a little proof that it can be done

Last edited by Schister66; 11-21-2011 at 05:25 PM.
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Old 11-21-2011, 05:24 PM   #55
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Quote:
Originally Posted by Schister66 View Post
Thanks, but i doubt very much I will be needing it. Furthermore, if it can't handle it in stock form, its a pathetic car and will be moving down the line.

A stock STi makes roughly 240awhp...to ask 380awhp of it is about 160% of its intended stress/power. For comparison's sake, my turbo GSR made 364whp on the stock block whereas a stock non-turbo makes roughly 160whp. That's more than double and still nowhere near pushing it to the limit. Several of my friends have run into the 400whp range with nothing more than a stock B series Honda, E85 and a turbo setup. It isn't rocket science provided the OEM parts are quality and your tuner is competent.
Inline engine =/= boxer engine


Completely different beast.
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Old 11-21-2011, 05:29 PM   #56
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It seems to me that if a smaller displacement, higher compression, NA car can make 400+whp in stock form, then a larger disp., sub 9:1, built-for-FI engine should also be capable of that power. I guess i shouldnt generalize

Last edited by Schister66; 11-21-2011 at 06:16 PM.
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Old 11-21-2011, 05:39 PM   #57
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Maybe this highlights my own ignorance for the way Subaru differs from other cars i've worked on.
It really does in more ways than you imagine.

Not sure why you need to come here and post your ridiculous calculations with your extensive experience?
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Old 11-21-2011, 06:03 PM   #58
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Other than justifying my previous statements, which is what someone does in a debate, i guess i didnt have a reason. Thanks for being such a helpful ass by the way.

Not sure why you needed to come in here and be such a prick..? Other than snuffing my ideas, it doesn't seem you've contributed anything to this, but thanks for trying

Last edited by Schister66; 11-21-2011 at 06:11 PM.
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Old 11-21-2011, 06:56 PM   #59
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I was trying to keep you from ****ing yourself but it appears you have your small mind made up and your arrogance will assure that.

Sadly you're too ignorant to catch on still...
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Old 11-21-2011, 07:45 PM   #60
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Thank you for your judgement of me based on a few posts. If you were able to give me some logical reasoning in contrast to my point, I would have listened. Instead, you took the juvenile route and called me names. Glad to see you're capable of behaving like an adult and having a discussion. Grow up
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Old 11-21-2011, 10:40 PM   #61
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Actually I only needed your first post to see you couldn't comprehend the over twenty logical posts before yours so you decided to post idiotic rationalizations about other cars. Genius.
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Old 11-21-2011, 11:40 PM   #62
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lol...
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Old 11-21-2011, 11:59 PM   #63
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Welcome to NASIOC.
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Old 11-22-2011, 12:45 AM   #64
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Quote:
Originally Posted by 04furesterXT View Post
Actually I only needed your first post to see you couldn't comprehend the over twenty logical posts before yours so you decided to post idiotic rationalizations about other cars. Genius.
Again, you're deflecting. You have yet to post anything to prove me wrong. I'm glad you laugh at my goals, but rather than being a condescending ass, you could have maybe posted something helpful/useful and said they're only reliable to a point, say 350whp or whatever.

Quote:
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Welcome to NASIOC.
...where all people do is bash each other since no one has anything useful to post.

Thanks for the warm welcome. Its good to see my Newbie status has erased all hope of credibility.

Last edited by Schister66; 11-22-2011 at 12:52 AM.
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Old 11-22-2011, 04:15 AM   #65
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To be very clear, 300+whp on stock EJ257 engine is definately unreliable for someone doing trackdays or rallying (let's say 4 to 10 times a year). We are a bunch of guys here having experienced pistons ringland failure and/or head gasket failure with stock/stage 1/stage 2 MY2009 to 2011 STis. Happens in a period between 5kmiles to 30kmiles.
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Old 11-22-2011, 09:31 AM   #66
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^^Now that's helpful. When do people start seeing ringland failure? Thats a failure i'm all too familiar with. Its the stock Honda curse...cast ringlands FTL. As for the HG failure, does anyone upgrade head studs to ARPs before boosting higher than stock? I'm not sure if that's a industry-wide thing or not...
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Old 11-22-2011, 09:34 AM   #67
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Quote:
Originally Posted by Schister66
As for the HG failure, does anyone upgrade head studs to ARPs before boosting higher than stock? I'm not sure if that's a industry-wide thing or not...
No one that I know of, unless they're putting in forged pistons/building the engine.

The studs/head bolts aren't the issue, proper cooling is.

EDIT: until you start getting into significantly higher boost pressures. Stock/stage2 aren't an issue.
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Old 11-22-2011, 09:35 AM   #68
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^^Good to know. Thanks
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Old 11-22-2011, 11:23 AM   #69
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I had my car dyno'd stock vs just a tune on stock and it went from about 264hp/280tq to 286.0hp/292.4tq. Would adding intake, EBCS, upping the boost to 19-20 psi, and tune be a concern for any failure?
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Old 11-22-2011, 11:40 AM   #70
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As long as the tune is good and you're not exceeding the limits of the fuel you're using, i can't see why it would be a problem. My STi is pretty much exactly what you just listed: Intake, 4" bellmouth dp, 3" catless Invidia exhaust, Grimmspeed EBC at 21psi, stock VF39 and a retune. It runs like a champ.
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Old 11-22-2011, 11:50 AM   #71
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Quote:
Originally Posted by aznboi0204
I had my car dyno'd stock vs just a tune on stock and it went from about 264hp/280tq to 286.0hp/292.4tq. Would adding intake, EBCS, upping the boost to 19-20 psi, and tune be a concern for any failure?
Ask your tuner.
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Old 11-22-2011, 11:51 AM   #72
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So excuse my nooblieness but what exactly constitutes a "built block?" Forged pistons and what else?
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Old 11-22-2011, 11:53 AM   #73
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Quote:
Originally Posted by STiSomeday
So excuse my nooblieness but what exactly constitutes a "built block?" Forged pistons and what else?
Basic: pistons, rods, bearings.
Complicated: the above with head work, valves, springs, retainers, cams, o ringed bores, etc.
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Old 11-22-2011, 01:12 PM   #74
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Again, if you are having trackdays or doing Rally with the stock engine, stock tune or good aftermarket tune, it will be an issue. It won't take more than 8 to 15 trackdays to fail (imagine this is less than 2kmiles on track, so it doesn't last long). A soft and good tune won't sort out the problem at all. I've not seen any 2.5L scooby that last more than that on track.
If you're using your car for daily driving only, even driven hard for a few miles on some occasion, then it won't be an issue until at least 50kmiles (some have more than 100kmiles without any pb) even with a good stage 2 tune.

So basically it is a question of what you're using your car for

At the opposite, the stock 2L STi engine is rock solid up to 380whp

Last edited by FRWRX; 11-22-2011 at 01:19 PM.
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Old 11-29-2011, 11:24 AM   #75
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^ he's right
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