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-   -   Th3Franz's engine build (http://legacygt.com/forums/showthread.php?t=207908)

Th3Franz 05-19-2013 08:49 PM

Th3Franz's engine build
 
1 Attachment(s)
10/7/2013 update:
https://fbcdn-sphotos-b-a.akamaihd.n...15029745_o.jpg

Core build is done. Just some loose ends to complete now.

Build list:
New 8.5:1 CR shortblock
JE FRS forged pistons
Manley H Tuff rods
King main and rod bearings
Top and skirt ceramic coating
New OEM oil pump
New OEM oil cooler
OEM head gaskets
ARP head studs
Machine work with torque plate (clearances for street/track use)
STI ported intake manifold
Gates Racing Timing Belt
Koyo Radiator
11 STI 6-speed trans
07 STI R180 rear diff


Rebuilt stock heads (8500 RPM limit):
GSC S1 cams
Ferrea 5000 intake valves
Ferrea 5000 exhaust valves
GSC Beehive springs and retainers
Manley locks
Pocket pord / Bowl blend


My car is at 95k miles (9 years) and I am planning an engine build. I think 350whp on 93 octane is making the engine approach the end of its life. I wanted to post up describing my build and get input from those who have done builds on Subarus.

My #1 question at-hand: I am rebuilding the heads; should I go with +1mm valves to support better top end flow for my DOM1.5XT-R? It is capable of holding 24 PSI to red-line already (see dyno run done at 23 PSI).

I did discover after the dyno last year that I had a small exhaust leak at the header and I had room for additional timing on the top end, which I safely added later.

Update 8/22/2013
Build plan below

New 8.4:1 CR shortblock:
JE FRS forged pistons
Manley H Tuff rods
King main and rod bearings
Top and skirt ceramic coating
New OEM oil pump
New OEM oil cooler
OEM head gaskets
ARP head studs
Machine work with torque plate (clearances for street/track use)

Rebuilt stock heads (8500 RPM limit):
GSC S1 cams
Ferrea 5000 intake valves
Ferrea 5000 exhaust valves
GSC Beehive springs and retainers
Manley locks
Bowl blend

jp233 05-20-2013 09:58 AM

Nice videos -- running at Road America, will wear out any engine on earth :)

I love RA, been there many times (racing motorcycles though). Last time I was there, July 2010, I think I may have made it into the 2:35 range (this is on a Yamaha TZ 250, nearly the perfect bike on earth available to mortals, however not necessarily the type of bike made for RA!)

Unfortunately, I don't have any useful knowledge on your questions :/

But, bigger is better right?

Max Capacity 05-20-2013 10:32 AM

I would not bother with the expense of bigger valves on a street engine.

I'd put that money towards the port work in the bowl area. I enjoy the troque in the midrange 2-3rd gear on the back roads.

Oh just saw where you mentioned a GT30R, is that more turbo then you'll use ?

The normal thing I add is to mauch sure you grease the starter shaft while it's out.

You've been here long enough you know the bearings and the other items are good.

Th3Franz 05-20-2013 10:55 AM

I'm running a DOM1.5XT-R which is essentially a 30R with a smaller turbine wheel. It holds 23+ PSI to red line no problem, so ideally I would like the engine to breath better up to 7500 RPM. I may go with a bigger turbo down the road too.
If I'm getting the valve seats machined with all new valves, is there any downside to going oversize?
I'd definitely like to do some mild port work and blend the bowl area.

Strizzy 05-20-2013 11:03 AM

I went with with stock sized valves with my ported/polished heads.
Supertech stainless intake and inconel exhaust. Supertech dual springs.
I'm also running Tomei 252/252 poncams.

I should have a dyno plot once I finished my motor break-in and get tuned on E85.

Th3Franz 05-20-2013 11:24 AM

Nice Strizzy. Hope this build works out well for you! What size turbo? Did you get a custom FMIC charge pipe made for running the metal 2.5i intake?

Strizzy 05-20-2013 11:45 AM

Turbo is currently a stock location ATP GTX3076R. New FMIC piping was easily fabbed up.
http://www.strizzyphoto.com/Other/Su...emapped-XL.jpg

I have purchased a compressor and turbine housing from ATP to convert my turbo to rotated mount and will be doing that shortly.

Max Capacity 05-20-2013 01:11 PM

Quote:

Originally Posted by Th3Franz (Post 4438288)
I'm running a DOM1.5XT-R which is essentially a 30R with a smaller turbine wheel. It holds 23+ PSI to red line no problem, so ideally I would like the engine to breath better up to 7500 RPM. I may go with a bigger turbo down the road too.
If I'm getting the valve seats machined with all new valves, is there any downside to going oversize?
I'd definitely like to do some mild port work and blend the bowl area.

If you have the funds, then go ahead and have the bigger valves installed, it will help later on with a bigger turbo.

The only down side I can see is the expense for a DD. But if your not using it as a DD more of a toy, then like Nike say's "just do it".

jp233 05-21-2013 08:42 AM

Bigger everything is never a bad thing at Road America!!! Granted I much, much prefer 2-strokes over all, but bigger valves will help with a huge turbo, you gotta get that air in and out of there well when you are just sitting there running through the gears with the throttle at WFO.

I say, if the budget allows and you're getting the head works done, why not go oversize ...unless it may be more difficult to tune or something?

Th3Franz 05-23-2013 05:21 PM

Stock engine is faring pretty well.
Compression: 130 130 120 130
leakdown: 4% 4% 12% 6%

m sprank 05-24-2013 03:05 PM

Leakage above 7% is considered a dead soldier by Subaru standards.

jp233 05-25-2013 09:54 AM

So sounds like a good time for a pre-emptive rebuild, because if something let go you'd be potentially in for more pain in the wallet due to other destroyed components (like the cases and the heads themselves).

Any thoughts on a larger oil pump? At least an OEM 11mm one, or I've read there is a JDM 12mm one.

Also, elsewhere I've read of some bad reviews of Supertech valves, but if your engine builder has had good luck with them, YMMV as always. You never know what you read on the internet too, about its credibility.

Any thoughts about using an external oil cooler instead of the OEM unit? I am thinking about it because the OEM one is expensive, $230+ and I think that's just stupid. I'm thinking about just using a universal air/oil cooler since I have tons of space behind the grill or lower valence (no TMIC). I would guess there are some plumbing changes I'd need to do for that coolant line, and replace the oil filter shaft with a shorter one (maybe one straight out of the 2.5i works or from an older 2.2). I also need to find out if there are any longer/larger oil filters that work if you delete the oil cooler. I haven't looked into it much, just got sore when I saw $230+ price for the OEM one...

Th3Franz 05-26-2013 08:39 AM

Wow Mike, I'm surprised to hear that Subaru has such a tight standard for leakage.

I'd like to go with a higher flow oil pump, probably a stock 11 mm pump.
I think the issues were with the cheaper Supertech valves. My builder plans to go with oversize stainless intake and oversize inconel exhaust Supertech valves.
An external oil cooler is probably a good idea. Mishimoto makes a universal one. I haven't looked into it much yet. $265 retail for the mishimoto one.

I found a nice plot for a similar setup as me. Same turbo with the same engine components pretty much on pump gas. He has a TMIC though and I have a FMIC. I love this curve.
http://img841.imageshack.us/img841/13/justind.jpg

m sprank 05-26-2013 09:52 AM

All Subaru engine specs are "tight" compared to most.

11mm oil pump is a good idea. 12mm JDM is overkill as would be a Orbit/ACL. I would run an external oil cooler with the OEM oil cooler.

JMLegacy 05-29-2013 09:29 AM

Mr sprank, I'm about to swap a vf34 and tune to 17psi on my JDM BL5. Do u think I'd need these test to proceed. My tuner and I think that would yield conservative power. daily driver


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