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Old 08-20-2007, 12:19 PM   #1
frayz
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Default EJ20 out.. EJ257 in. Advise wanted on spec please.

Hey guys,

Im thinking of swapping my 2ltr from my V7 STi for a 2.5 with some drop in forged pistons.

What bhp/torque are the stock rods safe to?

What power levels are you guys using these setups with and on what turbochargers?

I was wanting to run this setup and an FP Green turbo. Any opinions?

Remember i live in the UK and things here are much more expensive than they are over there in the states.

Any feedback or help would be greatly appreciated.

Cheers.
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Old 08-20-2007, 02:56 PM   #2
frayz
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Anyone?
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Old 08-20-2007, 03:56 PM   #3
Loubaru
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Most people will say around 400WHP, you can probably get more but its just a matter of time until you will need a new block
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Old 08-20-2007, 07:21 PM   #4
TROLL
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For added safety look into also doing Manley rods... they aren't very expensive and will definitely be stronger than stock. Not sure what shipping/importing would be like but I'm sure they'll be happy to help you with all of that if you get in touch with them.
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Old 08-20-2007, 11:00 PM   #5
STimo
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The stock internals will handle a green, add forged pistons to that and it'll handle a green no problem.. The stock rods and crank are pretty damn strong, and many people have ran 500+whp with just forged pistons andthe motors have lasted.. It really depends on how good your tune is.. i have ~25K miles on my stock STI motor, with 15K of them being at ~400whp with a GT30R and its still running strong.. Greens will usually make ~450whp on race gas, give or take a bit so with forged pistons added you shouldnt have a problem..
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Old 08-21-2007, 12:15 AM   #6
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You have what is mostly regarded as the best motor Subaru has ever built. Why are you considering swapping out for a 2.5L? If you're looking for more torque I can understand the desire for a change. As STimo said, it really depends on your tune. Forged pistons would be a good move, but there's no reason not to do other things that make sense at that stage of the game, aka the rods. It just makes sense while you're in there to do it. Look at some of the hybrid turbos such as the GT52, as people are making good power on them for stock location.
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Old 08-21-2007, 02:12 AM   #7
skiblur
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frayz, they are totally different feeling motors. I did the oppisite of your desires and swapped in an ej207, which we did not get stateside and absolutely love it. I daily drive with a green actually, it works very very well. In my personal opinion the ej207 does not make power as easily as the 257, but is more capable of supporting high power levels.

plus, you know your going to miss 8k once you get rid of it. The only appropriate solution in your case is to build a 2.5 bottom end that will spin to 8k. best of both worlds.

In all seriousness though, I would much rather to kelford cams, a nice .63 gt30 and proper blowthru tuning on a 207 than 257.
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Old 08-21-2007, 07:46 AM   #8
frayz
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Cheers for your input guys.

I want the added torque of the 2.5 really. Its a very cost effective way of making the lardy @ss newages into a quick car.

If i was going to add rod bolts, then i would change the rods and bearings too.

However i was hoping to just do the forged drop in pistons so i dont have to split the new bottom end.

Any other thoughts ?
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Old 08-21-2007, 01:57 PM   #9
frayz
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bump for more feedback
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Old 08-21-2007, 04:49 PM   #10
frayz
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bump?
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Old 08-21-2007, 05:14 PM   #11
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yeah you can do just pistons and you should be good, i just thought you were looking for a little more insurance there.

as for the 2.0 vs. 2.5 argument... in the US they say they love the v7 and v8 2.0L, but in other countries they desire to have the USDM 2.5L... the grass is always greener on the other side i guess.

and to the guy who suggested the .63 housing on the 30r... yuck! its a hack and a half, which is why Garrett does not sell the turbo this way.
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Old 08-21-2007, 05:19 PM   #12
frayz
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think im gonna just run a 2.5 with pistons and a 7cm 3" green

See what happens
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Old 08-22-2007, 05:11 AM   #13
STimo
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I'd go rotated if i were you, it's a better setup, comes with an external wastegate, is capable of making more power, turbos can easily be swapped to make more power, and since you have forged pistons the motor will hold the power for a long time..
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Old 08-22-2007, 03:05 PM   #14
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7cm Green with an EWG for mad power yo!

alky too?
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Old 08-23-2007, 07:41 AM   #15
frayz
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Im looking at an Axis Stg 2 bottom end due to them being such good value.

Any opinions on the Axis stg 2 blocks? What bhp/lbsft will these take?
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Old 08-23-2007, 09:33 AM   #16
MNAutomatic
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Why did you make a new thread about a question you just placed in here? Anyways, I answered it in the other thread but I will say it again. Axis motors are great and few people have had problems with them. Do a SEARCH for axis motors and you will find plenty of people who love their motors
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Old 08-23-2007, 04:27 PM   #17
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around 450 horsepower
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