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Discussion Starter · #1 · (Edited)
Came here looking for a td05 turbo to upgrade my td04, but actually really like this forum. Figured I’d share my car.


Here’s my “nearly done” project. I still have a lot of kinks to work out, but everything roughly works at the moment.

The car started as a 66 bug. It has a 95 ej20g in the back seat with a wrx tranny. I have an sti tranny ready to drop in, but waiting for the big boy engine from the machine shop to run that. I’ve been working on this forever, it keeps going through different renditions and this is the latest one.


Engine:
95 ej20g, forged pistons, sti rods with arp bolts, bearings with extra clearance, arp head studs. stock ecu with robtune 550 tune, td04h turbo at 18psi, one step colder plugs, lightweight flywheel and pulley. I’m running an air to water intercooler setup with a tank, heat exchanger, and a massive pump, it actually holds more water than my cooling system. Added a killer b pan and pickup after oil starving doing doughnuts

Cooling: Mishimoto radiator for a Honda engine, and a high flow fan. Had to add an electric water pump because I couldn’t move enough coolant at idle and around town.

Tranny:
03 wrx (the beefier one), 1/2 and R&P polished, shot peeled, and knife edged. 4.11 R&P, shorter 5th gear. Made into a transaxle by removing the center diff and output gears. Clearanced for an sti clutch. Currently running a s wrx clutch, might throw the 6 speed clutch in, I think it slipped in 3rd with my nitrous. Cv joints are polished Porsche 930’s

Nitrous is a nitrous express proton. Only used a 50 and 100 shot so far. Capable of 150 but haven’t tried it yet.

Full roll cage, and my buddy made an easily removable engine and tranny cradle.

Brakes:
Fronts are made by airkewld, they use 4 piston wilwood calipers. Rear are made by cnc, and use their 4 piston calipers and an 11” rotor. Cnc hand brake.

Suspension:
Rear suspension uses the Vw trailing arm found in later vw’s. But the inner and outer mount are 3/4” heim joints. I’m running fully adjustable qa1 coilovers
Front suspension is a double a arm setup from imohr, a company in Brazil

Wheels:
I have a track set of Porsche cup 2 wheels with nitro nt01 tires. Front I run 205/45/17, and rears are 255/40/17. I have a drag rear wheel set with real wheel racing beadlock rims, and MT ET street 235/60/15 tires. I’m also getting a Porsche knockoff set of wheels for daily/burnout use.

I’ve got a bunch of random stuff, racing seats, removable steering wheel, gauges, 150mph speedometer.

I both love and hate this project. It’s a massive time and money pit, but it’s fun when it works. It weighs in at 2000lbs, I might gain the 75 pounds if I put in the sti tranny.


Pics in the next posts
 

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Discussion Starter · #2 ·
Walk around

Video of my nitrous testing, speedo is off 75mph = 65 actual

















Got my front end mostly together. Double a arm setup from imohr in Brazil.







 

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That's pretty dang cool! Having owned ej20g's for years, I'd encourage you to use a VF series STI turbo instead (VF23, vf39, vf48, etc). You'll just need to use a silicone 90* fitting to make it work. The factory td05 is dinosaur technology, and is super laggy on the 2.0L. The VF turbos spool way faster, and can now finally be rebuilt if needed.
 

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Discussion Starter · #5 ·
That's pretty dang cool! Having owned ej20g's for years, I'd encourage you to use a VF series STI turbo instead (VF23, vf39, vf48, etc). You'll just need to use a silicone 90* fitting to make it work. The factory td05 is dinosaur technology, and is super laggy on the 2.0L. The VF turbos spool way faster, and can now finally be rebuilt if needed.
Oh sweet!
I was worried about using a VF because it’s not what the tune was designed for (robtune with a stock ecu), and because I’ve heard of silicone 90 hoses collapsing. But good to know, a buddy was trying to give me one a few years ago. I may hit him up.
 

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The rob tune is somewhat flexible. You can't change your injector or maf size, but you can change turbos a little bit.

I bought my silicone 90s from Silicone Intakes

Never had a problem with them collapsing, though I could see that happening if you got a single ply 90 that's not designed for boost.
 

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Discussion Starter · #7 · (Edited)
Killer. I’ll get the car a bit more sorted, and get a bigger turbo!

I should get my sleeved, big boy 2.5 running, but I’m also mildly scared to have a lot more power
 

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Discussion Starter · #8 ·
The rob tune is somewhat flexible. You can't change your injector or maf size, but you can change turbos a little bit.

I bought my silicone 90s from Silicone Intakes

Never had a problem with them collapsing, though I could see that happening if you got a single ply 90 that's not designed for boost.
I did get that turbo swapped, went on one drive and in true Subaru fashion, killed my engine. Again.. From spinning bearings.

If my next engine dies, I’ll swap in a Honda K motor.

I can’t post in the for sale section because I’m new, but I’ll be parting out my ej20g engine if anyone is interested in parts. Including the robtune 550 tune and parts, wired to run as a stand-alone ecu.
 

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Sorry about the heartache.

I wouldn't trust a 25-30 year engine not to crap out with regularity. Rob's tune is basically maxing out the old hardware. And even though it's a flexible tune, it's not tolerant of compression above 8.5CR (straight from Rob's mouth)

I'd recommend rebuilding whatever next engine you get, with new rings and bearings. Rods and Pistons are not needed at this power level. And start out with the stock ecu tune during the breakin period.

That's how I got 40k miles from my old robtune build. Before I rebuilt that engine, I was getting 5 (seriously) - 5000 miles on used, non-rebuilt engines. You just can't trust that the previous owners didn't destroy/run out of oil/run on regular octane fuel/etc the engine.
 

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Discussion Starter · #10 ·
Sorry about the heartache.

I wouldn't trust a 25-30 year engine not to crap out with regularity. Rob's tune is basically maxing out the old hardware. And even though it's a flexible tune, it's not tolerant of compression above 8.5CR (straight from Rob's mouth)

I'd recommend rebuilding whatever next engine you get, with new rings and bearings. Rods and Pistons are not needed at this power level. And start out with the stock ecu tune during the breakin period.

That's how I got 40k miles from my old robtune build. Before I rebuilt that engine, I was getting 5 (seriously) - 5000 miles on used, non-rebuilt engines. You just can't trust that the previous owners didn't destroy/run out of oil/run on regular octane fuel/etc the engine.
This engine was rebuilt twice. Fist time after spinning a rod bearing. King/ACT bearings, forged pistons, sti rods, ARP head studs. Oil starved it after doing doughnuts. Rebuilt it again with pretty much the same build and a killer b oil setup and it spun bearings again.

Next engine is almost ready to roll, but really beefy.
Shooting for 450whp but it’s even overbuilt for that.
 

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Yeah that's overbuilt for sure. I have a bad feeling that the location of the engine is contributing to it starving itself of oil. You didn't mention the oil pump size, if it's larger than 10mm, that's not a good thing.
 

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Discussion Starter · #12 · (Edited)
The motor that kept dying had the stock size pump. I’ve read about potential issues from having too big of a pump, but still haven’t found a conclusive failure from too big of an oil pump. If there’s something out there lemme know!

The next engine is sleeved, arp case studs (case took a lot of machining apparently), ARP 625+ head studs, sti heads, JE FSR pistons, king bearings etc. I am using the 12mm oil pump. Heads are dual AVCS but I deleted it by running 205 cams
 

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What is the compression on that? And are you still on a robtune? I'm running a 10mm factory oil pump on my single AVCS ej207 engine. When cold I'm getting 80s-90s psi, and when warm I'm getting around 30psi, both at idle. When it's warm and under load (over 4500 rpm and rising), I'm over 80psi according to my gauge.

My understanding of the larger pumps is they provide more oil flow at lower RPM's.
The 10mm pump's bypass opens at 85psi
The 11mm pump bypass opens at 75psi
The 12mm pump bypass opens at ?? PSI? (couldn't easily find that).

What I gather from that info is on my personal car with it's 10mm pump, I'm nearly at/just below the bypass valve opening pressure when the engine is hot and under load. What happens if I'm operating at the valve cutoff? (I don't know the answer, but reading a lot of Homemade_WRX's, KillerBMotorsports, Crawford Performance and Dom Acia's posts a) makes me feel stupid and b) makes me believe that the larger the pump is not better nor is warranted for most builds due to the pump's bypass opening and not giving any higher flow at high rpm's)

Lastly, you mentioned putting ej205 non-avcs cams in a quad avcs head? I didnt think that was possible?
 

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Discussion Starter · #14 ·
What is the compression on that? And are you still on a robtune? I'm running a 10mm factory oil pump on my single AVCS ej207 engine. When cold I'm getting 80s-90s psi, and when warm I'm getting around 30psi, both at idle. When it's warm and under load (over 4500 rpm and rising), I'm over 80psi according to my gauge.

My understanding of the larger pumps is they provide more oil flow at lower RPM's.
The 10mm pump's bypass opens at 85psi
The 11mm pump bypass opens at 75psi
The 12mm pump bypass opens at ?? PSI? (couldn't easily find that).

What I gather from that info is on my personal car with it's 10mm pump, I'm nearly at/just below the bypass valve opening pressure when the engine is hot and under load. What happens if I'm operating at the valve cutoff? (I don't know the answer, but reading a lot of Homemade_WRX's, KillerBMotorsports, Crawford Performance and Dom Acia's posts a) makes me feel stupid and b) makes me believe that the larger the pump is not better nor is warranted for most builds due to the pump's bypass opening and not giving any higher flow at high rpm's)

Lastly, you mentioned putting ej205 non-avcs cams in a quad avcs head? I didnt think that was possible?
If I remember correctly, those heads make it a 9:1 compression, maybe a tad higher since the block and case half’s got machines down, but maybe not enough to even count.

I’ll be running a megasquirt setup, I need to wire it this week, and figure out what I’m doing with the software.

Since I’m running the megasquirt (microsquirt 3), I don’t have the option, and didnt want to figure out a way for the avcs to work. Looked on NASIOC and saw you can just run 205 cams (which I had). Had to order new pulleys though. I had to keep the avcs solenoids since the oil passages through them provide oil to one a cam journal. I might upgrade to bigger cams later, but I have a feeling I’ll make enough power to scare myself as is.

I may have to keep looking into the oil pump thing. I read some stuff previously, but the threads were very old. I have a feeling you may already be operating at oil pump overflow. Isn’t it spring tensiones like a wastegate, and just regulates high oil pressure by opening and adjusting? Maybe someone can school me on the matter.
 

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Discussion Starter · #15 ·
Here’s the engine I’m putting together

86739


86740


86742



And here’s the tranny from a few weeks ago after a ring gear bolt backed out (I didn’t locktite them)
86743
 

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That engine looks amazing! I really hope this engine meets your expectations.
 

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Discussion Starter · #17 ·
(Ran out of room for more pictures in my last post)

Luckily I had an sti tranny pretty much ready to go. She’s heavy though, it added 75lbs over the wrx 5 speed. I only got one drive in it before ge engine died, but the gearing felt nice, and the shifting felt cleaner.

86745
 

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Discussion Starter · #18 ·
That engine looks amazing! I really hope this engine meets your expectations.
Me too! I spent enough for it to. Again, I could have met my power goals with a Honda engine, but didn’t know it at the time.

If I wasn’t working so much, I’d try to get it running in the next week. But I’ve been slammed, and not sure when the car will drive again.
 
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