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Shane818 01-13-2008 04:21 PM

Hybrid with build or keep it simple?
I have an 02 wrx and have been talking to some local wrx people and a couple shops and the 2.5 short block swap with the 2.0 heads seems like the best deal instead of going for the whole STi swap. dont really want to switch the wire harness etc etc. So a hybrid motor will be done. I plan on swapping the pistons and rods for the block. Now for the head i want to upgrade the cams and have it ported out pretty good. The head has to go to the shop when you put the shortblock in so why not do some minor upgrades right.

Here is where the dilema starts. I usually dont shoot for dyno numbers at all. But i want to end up with 350 whp. a little less is fine. a little more is also fine. with that 300HP mark being broken the tranny obviously has to be upgraded with some new gears. which then calls for new clutch and flywheel. fine. now as far as turbo upgrades, this is the point which i am stuck at. having a somewhat built hybrid motor with a almost undestructable tranny i can pretty much choose what turbo i want. what do you think is best for my situation? I have been looking into a rotated turbo mount from!Thumbs Up, simply amazing product the build, but am not sure if the turbo will be to big. Something that will put me in the 350-390 range is prefect.

any help is appreciated. Anyone who is running a hybrid motor how do you like them and what are you running. thanks.....

Jave 01-13-2008 04:48 PM

go with the hybrid. I have my stock tranny on mine and you just ahve to watch how you drive until the tranny is able to be gone through. I didnt go with a rotated turbo but a SZ-49 and I am fairly certain I am at/around 350HP so your will be fine. I love the throttle response preturbo now and my smile only gets bigger as the boost builds, you will not be disappointed.

Hybrid motor:
stock heads PnPed
SZ-49 turbo with supporting mods

Boostbuddy 01-13-2008 05:31 PM

The EJ20 heads flow great with a port and polish !Thumbs Up

Valve train work wouldn't hurt either

TwoCobras 02-29-2008 12:59 PM

I just--finally--finished a hybrid build. And now I have to sell the car because I'm taking a job overseas. Damn.

Here's what I did:
EJ257 block
CP pistons
Crower rods
ARP headstuds
new water and oil pumps, new tensioner, belt, etc.
EJ20 heads
Leave the heads alone except for deshrouding and cleaning and checking valves for fit. There is no reason to port and polish because:
Crower springs and retainers
Cosworth cams. The cams are the key. You can port all you want but if you don't have the right cams you are wasting money. The Cosworth cams give my engine all the air it could ever want (unless you are going for stupid horsepower, i.e. more than 600 whp).

Perrin fuel rail
Walbro 255
Stock injectors bumped to 810cc by WitchHunter (waaaaay better than PE's)

All major hoses and intake are silicone. Perrin catch can.
Stock intake box with stock Subaru filter (plenty of air. Intake is dismantled to the box, and hole in fender where intake formerly went is closed. All air now comes from the fender. Easy to do, and more effective than anything that gets air from inside the engine compartment. Do not use KN filters. OEM filters are fine unless you are going for more than 500whp).

Aluminum radiator. The stock radiator is not enough.

Blouch TD06-20G turbo. This is more than enough turbo if you are staying under 500whp. Blouch makes a slightly better turbo for another three or four hundred dollars. Call them. They are the best that I've found when it comes to turbos. Also the most cost effective.

I'm using an AVO topmount with AVO bov. Too much gravel and sand on the roads where I live for a front mount. In fact, the car has a spray-on bra for front-end protection. JDM STi hood scoop.

If you stay under 500 whp, the stock ECU is all you need. Dom at getadomtune can give you a good tune over the Net. Best tune is by Dom on Kito's Mustang Dyno at Kito's in Seattle. But anyone with a Mustang Dyno should be able to set you up. If you are on the East Coast, contact Andrewtech for references.

Trans: I put in Albins gears, instead of PPG. Both are comparable, but Albins has a one-piece input shaft instead of two-piece, and is thus a little stronger. If I had to do it again, though, I'd go with PPG because Dan at Andrewtech really knows what he's doing, and because PPG stands behind their product much better.

Clutch is a Clutchmaster's 300 Kevlar. Very smooth. Takes no more effort than OEM clutch.

At the moment mine is tuned to 300 whp/270 wtrq. But this is only because when it was tuned it had stock trans. With no timing to speak of in it, and only 5 pounds of boost (we flashed the ECU as conservatively as possible so we could drive the car over to Seattle to do the tune), first run on the dyno, the engine put out 315whp/over 300 trq. Had to dial it down for fear of shredding the trans on the dyno. Long story short: next tune, I want it at about 400 whp/410wtrq. Remember, this is on a very conservative dyno, perhaps the most conservative in the country. The stock EJ20 heads are good to about 600 whp (with methanol injection).

Option: take out the tumblers. They really are not necessary. I left mine in, but wish I had taken them out.

Hope this helps. Even at 270 wtrq and 300 hp, mine is a monster. Another 100, and it is going to be a handful. At present, with very little timing in it, I'm getting 30 mpg cruising at 70 mph.

TwoCobras 02-29-2008 01:19 PM

Sorry. Forgot to mention: stock flywheel is fine. Make sure to have it turned, however. For daily driving it is better than a lightweight. Also, you need an aftermarket boost solenoid (about $50).

Longshot 02-29-2008 02:05 PM

That is a nice setup dude, it's really too bad you have to sell it. With the support of fine tuning you really coud make some massive whp with that. Can we get pics?

Shane818 02-29-2008 03:13 PM

pics would be awesome. congrats on the whole build as well. I am really looking forward to getting this underway. But i am taking my time because i would rather buy better parts then go cheap and blow up an engine. I am looking for basically the same type of car you are. Nothing over the top, just a great engine that puts down enough power to hand some people their ass. sucks you have to sell it.

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