RomRaider

Mine reads B25C 703 on both sides. Must be the new casting. I wonder where it is made cause it says Japan nowhere on it and many people have notice a difference in the new 703 casts.

Picked up my connecting rods yesterday, time to get goin on the shortblock....

Current plan is:
Eagle rods (got em)
Wiseco pistons (on order)
Crower 272 cams (on order)
Crower Valve springs/titanium retainers (on order)
75mm steel crank (balanced and polished)
2.0L heads (ported and polished)
Holset HX35W (looking for one)

Displacement: 2.35L
Compression: 6.7:1
Power goal: 550-600 wheel
Boost goal: 25-30 on pump

Lets see what happens.


Friggen Crower and Wiseco are killin me.. still waiting on pistons and cams... grrrr

Holy crap. That is one low CR. Are you getting it balanced?

Yup, crank's already done, good for 10,000

Sweet. I wish I had the funds to do the same. Just dropins for me.

I did find the "Japan" label on my block.

Dang I just sold an HX35W on Craigslist not 3 weeks ago! That sounds like a super sick pump fuel setup man.

Thanks man, thats what I'm goin for...

awww, why isnt it on your car?? lol

mike, what's the stock exhaust housing size of that hx35? 12cm?

from the little bit of data i can find here and there on the web it seems like it'll push about half a kg of air a second, probably around 500whp on pump gas.

your motor is gonna come on like a banshee when that thing spools up to 3 bars... :devil:

Those holset turbos are awesome.

Yup, 12cm^2 exhaust housing
And its twin scroll, and its twin entry compressor, and its got an internal wastegate (which I plan on using), and its efficient to 44 psi, and oh man do they sound cool.... 4.25" inlet

500 on pump would be allright lol

I tuned a celica a couple weeks ago. JDM 2.0L, cams, bolt ons, AEM stand alone, and a holset HX35....... made 329 wheel @ 14 psi with 24 degrees timing on a brand new motor. That was my "nice" break in tune. That pretty much sealed the deal what turbo I'm going with. Because of the compressor design, it doesnt lag like you think it would. Theres a lot of available airflow and boost before and during spoolup, which I thought is pretty sweet.

Are you back in Dudley? And if so, can I get a ride in that thing this summer?

what is your reason for going with such low compression? isnt the car gonna be a total dud out of boost?
i dont know, i was taught that low compression/high boost is and old philosophy based on old technology and doesn't apply nearly as well to today's engine setups.
when i was going to do a built 2.5L i was going to aim for 9:1 on pump gas with moderate boost... and make good power on and off boost. nick at je strongly recommended this as did some others.
curious to your reasoning for going the other direction...

seems to me like he wants to run a lot of boost, and doesn't really care about torque under the boost threshold.

so you run a low static compression and put a high pr turbo on. for example, a diesel turbo.

the age of the technology has little to do with it. engines make power from fuel and air, and if you put more of those in, and light it off properly, you'll get more of it out. that hasn't changed in 100 years.

from the looks of his specs he might be destroking a 2.5 block, which will do well to net a long rod/stroke ratio, reduce CR, and still preserve quench.

Ken's got it. No matter how much technology exists, at 9.0:1 CR, 20-22 psi with a good flowing turbo is really pushing the limits of whats "safe" on pump gas. Sure you can run that much or more boost with less ignition timing or more fuel, but thats not going to make power. So instead, I'm utilizing a different technology. Twin scroll, high rpm, high flow, high boost diesel turbo. Yeah its gonna be a little laggy off boost, and its not going to make much NA power, but its a worthwhile trade off (I hope) to be able to run very high boost on pump gas. And Ken is also right, I'm de-stroking a 2.5L, so by doing this, the usable operating range of RPMs will be greatly increased, so even with a late spool, there should still be a lot of area under the curve. The whole build with the de-stroke and low compression isn't something thats really proven out yet in the subaru world, so in addition to the theory, its also going to be a good experiment of whether or not this type of modification responds well on a EJ motor....

The bigger turbo you go, the lower you want your CR. This has not changed for years. It is all a about cylinder pressures, and with that high rpm, big ass turbo, you don't want anything greater than 8:1 really.

The de-stoke is what really interests me. The EJ motors are already over square, but this will put it way over square, so that motor will be able to rev like no other. At 8K RPM, that thing is going to be screaming! Let me know how it goes. My next motor build, I might have to copy you Mike.