My 73 Suby drivetrain conversion upgrade!, Added a quick video on page 25 Options

[76-914]

Horse Power is addicting. Glad to hear you're back in the saddle, Jamie. Get'er running. (IMG:style_emoticons/default/beerchug.gif)

[Amenson]

New is good for piece of mind. I was planning to just upgrade the rods pistons but once I got into my engine a crack in cylinder and "while I am at it" ended up in this!



Everything in the picture is new...except the crank bolt. I was just using the old one for assembly. I looked into IAG short blocks but they didn't offer a higher compression piston option and the lower stages used standard size pistons and no other machining, just new case halves. I need to update my build thread with the specs but it should be solid for something over 600 crank hp and I am into it for ~$3k including a complete gasket kit and upgraded springs and Ti retainers, because...8k rpm.

Granted I don't have a warranty and spent 100 hours researching, measuring, and assembling plus I will be a nervous wreck until it is broken in holding all the boosts but I saved a few grand and learned a bunch in the process.

Check with the short block supplier which oil pump to run and consider a cast impeller water pump. Not sure how you are going to source an engine harness/ecu but consider getting a throttle by wire unit and definitely confirm COBB Accessport availability.

Check my thread for ECU position and harness routing. There were only a few wires I had to lengthen to get it there. PM once you get into it and have detailed questions.

Cheers,
Scott

[JRust]

Looks great Scott. Well done building it. Yeah IAG short block is what I am getting. Only real question is using my 2.0 heads & getting a 2.0 dish in my pistons. Making it a bit of a hybrid. I would do new cams & springs. Just not sure how much performance I would give up over the 2.5 heads. It would run another 800 bucks to do 2.5 heads. Wish I knew all this stuff better.

[dan10101]

I'm glad you're doing a 2.0

Here's a Mighty Car Mods video on Sub 2.0 short block.

Start at 2:00 and at least thru 8:00

https://www.youtube.com/watch?v=Ge_S3Rm1vQ0

[Amenson]

I'm glad you're doing a 2.0

Here's a Mighty Car Mods video on Sub 2.0 short block.

Start at 2:00 and at least thru 8:00

https://www.youtube.com/watch?v=Ge_S3Rm1vQ0

The video is accurate but not directly relevant to Jamie's choice. Most Subaru engines do not have forged pistons, some special editions did and apparently that is the shortblock they ordered. My 05 STI engine (EJ257) did not which is why I opened it up. The pistons are pretty much guaranteed to fail once a bigger turbo is used and some guys with crappy tunes are having failures with the stock turbo. My pistons were fine when I pulled them running 305 whp, even with the sporadic road trip trifecta of death: crappy fuel, heat soak and shenanigans.

The other benefit of that particular short block (and probably all 2.0's) is the semi closed deck. The EJ257 is also the same semi closed deck and this is what IAG uses. I think that the NA 2.5 engines are completely open deck and definitely undesirable.

Even IAG's lowest spec 2.5 short block that uses the factory forged rods is plenty strong/robust for what Jamie's plans are.

The 2.0 head hybrid setup does seem to be desirable for some reason but I have not researched it.

Chris's link to subiperformance is a good channel to watch. They build some really amazing engines.
I also like Flatirons Tuning
They have some really good videos about oil pumps, PCV system and other things. I would be surprised if they do not discuss the hybrid setup.
Edit: they do...
Hybrid Video

[JRust]

I keep changing. Found a JDM motor a guy wrecked his car. Got to hear it run so going to take the plunge & throw it in. Hopefully I can enjoy it for a while before I need to build a new motor

[rhodyguy]

With the full on rebuild what do you do about heads?

[JRust]

With the full on rebuild what do you do about heads?

Either get new 2.5 head or I can use my 2.0 heads with some changes. The IAG block can come with 2.5 pistoins dished out like 2.0 pistons. Then you use a little thicker headgasket with the 2.0 heads. Otherwise it throws off compression numbers.

[76-914]

Good move. Anything is better than nothing. Get her moving! (IMG:style_emoticons/default/beerchug.gif)

[Andyrew]

I keep changing. Found a JDM motor a guy wrecked his car. Got to hear it run so going to take the plunge & throw it in. Hopefully I can enjoy it for a while before I need to build a new motor

Where are you going to keep your power level at? I say a JDM motor is a great option. Keep you on the road and should hold enough power to be plenty of fun (IMG:style_emoticons/default/smile.gif)

[JRust]

Okay haven't made any progress. Between buying a used JDM motor which turned out to be crap. Then different builds my shop suggested. Lack of money to really build a nice solid motor. I have been kinda stuck without anything to really get excited about. I've had a run of bad luck with my conversion to say the least. I always keep my eye's out for a deal. I came across a wrecked 2002 wrx. Nothing to special at first glance. Emailed the guy & made a trip up to see him. Turns out the motor has 25k on a full rebuild with a lot of goodies. No oil leaks & runs great. Dyno's at 308hp at 17lbs or boost. I've got a larger turbo but think I am going to run it basically as is. With it dialed in the way it is. I am going to just keep all my newer high priced stuff from my spun bearing motor. Hold onto it for changes down the line. Taking it to my shop tomorrow & will get a more informed opinion. Keep your fingers crossed everyone. I may just get to drive my car again soon

[Andyrew]

Nice!!!! 308 whp at awd is like 330whp

Thats pushing some steam! They must be running an aggressive timing table. Keep a steady eye on your fuel!

Your making the right steps in the right direction!!

[JRust]

Well I picked my car up today from the shop. New used motor is in. The 2002 wrecked wrx I bought for the motor. 25k on the rebuild which I felt good about as I got to hear it run. Didn't see any oil leaks but of course on pulling it found 3 different ones. Ended up having the motor resealed. Setup isn't perfect & I definitely have some more work ahead. My Stinger ECU is a bit limited. Sending off my wiring harness to get cut down for standalone. Then I'll swap my intake & use a stock ECU. This will make getting tunes much easier. Also capable of more HP. That is down the road. I plan to just drive it for a while as is & enjoy summer. The second is my intercooler setup just isn't great. My intake temps are limiting me as well. So will be looking to follow Andrew's advice on going air to water intercooler.

Only other issue is I think the Dyno guy tuned my car with my ebrake partially engaged. My passenger rear caliper decided to start leaking profusely after the session. Pretty sure he cooked the seals as they are PMB built & really don't have all that many miles on them. Oh well pulled the caliper off my other 73 resto. I'll put it on tomorrow afternoon & bleed the brakes. Then I can actually go drive my car & see how I like it.

The dyno tune only puts me at 250hp now. Due to the intercooler & ecu restrictions. I won't get it much better until I have changed them. Still quite the bump from my previous 158 with my NA setup. Excited to drive it & really feel the turbo. I sure hope all this has been worth it

[76-914]

Damn right. Go Jamie, go. I can’t tell you how excited I am for you. It always seemed to me that life was giving you a bit of a runaround when it came to bumping up your HP. But you never backed down and were always ready for the next problem whatever it might be. Go Jamie, go. (IMG:style_emoticons/default/beerchug.gif)

[Amenson]

Way to stick with it. What about the Stinger is limiting performance?

[JRust]

Okay this has been a long time coming. Replaced my leaky rear caliper with a newly rebuilt one from PMB. Still need to bleed the brakes a bit more but was good enough to test it a bit. It is raining hard today so m test drive was a tame one. Kept blowing a fuse to my wipers & defrost doesn't do much without a little heat. So had to keep wiping the window with a rag. Went into town to fill it up with gas. MY gauge isn't working to well & showed empty. Took 12 gallons so glad i went to fill it up. On the way back home jumped onto the freeway real quick. Went from 30 to 80 in holy shit fashion (IMG:style_emoticons/default/evilgrin.gif) . Then had to back off for traffic. Then got off & went back home. Would love to drive it more but not doing it in the rain. I will say I was very happy with how it felt. That turbo pull is something that just puts a big ass smile on your face.

Next up figure out why I am blowing a fuse. Run a wire to my speed sensor on the tranny to my Speedometer so I can tell how fast I am going. Build a new center console & install my new Factory 5 shifter. Replacing my MR2 shifter. Then drive it the rest of the summer

[JRust]

duplicate

[dan10101]

Driving it! That's a good thing!

Sounds like a fun day!

We actually we had our first autocross event of the year today. But it ended up with me driving home at 11am in a thunderstorm wiping off the inside of the windshield as well.

Tomorrow summer is here!

[Andyrew]

Awesome!!! Glad to see you get that car out and about!!! 250 is a nice number for these cars with a turbo. Good amount of turbo feel and certainly very quick!

[Tdskip]

@Jrust - what was wrong with the JDM engine? Can I ask where you sourced it?