subaru 2.5 turbo (sti motor)

xnoregretsx

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anyone ever heard of these things being put in a truck?

interested in finding out if advanced adapters or if anyone makes some sort of transmission adapter to fit one of these things? or would i have to use the subie transmission too?

planning a build for a early 90's extended cab yota 2 wheel drive since i dont think i can use the all wheel drive aspect from the subie

center mounted arms front motor 2 seater truck

i dont want to race it i just want to build a fast/light truck i figure the subie motor makes about 320 crank horsepower and 305 ft lb torque. and 2k$ later in motorwork and tuning 450-500 hp at around 3800 rpm...

im thinking its gonna be able to get out of its own way with a quickness.
 

dirtdudeaz

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well I know that the suburu transmissions don't hold up a little bit past stock power. So I would reccommend putting in one of their "race suburu" (cant remember which one it is...the high end race suburu has it)transmission.
 

GHARACING

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anyone ever heard of these things being put in a truck?

interested in finding out if advanced adapters or if anyone makes some sort of transmission adapter to fit one of these things? or would i have to use the subie transmission too?

planning a build for a early 90's extended cab yota 2 wheel drive since i dont think i can use the all wheel drive aspect from the subie

center mounted arms front motor 2 seater truck

i dont want to race it i just want to build a fast/light truck i figure the subie motor makes about 320 crank horsepower and 305 ft lb torque. and 2k$ later in motorwork and tuning 450-500 hp at around 3800 rpm...

im thinking its gonna be able to get out of its own way with a quickness.


2k??? id love to know how you make that much power with such small funds. i have a FULLY built sti and it only putting down 430ish to the wheels (pump fuel)...
 

xnoregretsx

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2k??? id love to know how you make that much power with such small funds. i have a FULLY built sti and it only putting down 430ish to the wheels (pump fuel)...

my secret is.. i already have the bigger turbo intercooler and everything except ecu and injectors :) i should have mentioned that i guess thats why i wanna run a subie motor cuz i have over 5k in parts for one
 

xnoregretsx

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2k??? id love to know how you make that much power with such small funds. i have a FULLY built sti and it only putting down 430ish to the wheels (pump fuel)...


by fully built do you mean you have the fully inclosed block ?
also are you running a EJ257 motor?


fully built ej257 long block with a port polish and stroker kit naturally aspirated will put down 450... with a garrett gt35r turbo walboroh (spellcheck) fuel pump and pink 850cc sti injectors, machined lightweight pulleys and custom tune by me, along with one off intake/turbo mount and inercooler .. i should be at around 550 on 91 octane ... 6-700 on race fuel and mapping.


when the parts were on my 04 sti with the un-sealed short block i had it tuned back to about 425 hp 415ftlb @3700 rpm 18lbs boost, daily driven throughout the week... beat the hell in the snow, sand, desert, track on the weekends. the stock transmission held up quite well although i did have a stage 3 race clutch installed along with some transmission internals for strength.

if i can come across another matching gt35r turbo or even two slightly smaller turbos
and a set of titanium/aluminum alloy race heads for the ej block i can get 850 streetable/baja ready horsepower


its nice to know im not the only guy on rdc that loves subaru performance
 

dirtdudeaz

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I was talking to a buddy today. He said that the 4wheel drive on a suburu is different than a truck. So you would need a different transfer case/gear box etc for that setup. But it sounds pretty bad ass. Those motors haul ass
 

cusico

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the sti is the transmission to go to, then upgrade to dog engagement gears 10K.

You can, just like they have done for the Subaru drift cars, just lock the center diff (weld), or cusco center diff, and then just run the driveshaft into a toyota transfer case or straight to the rear diff for a 2wd setup.

The available Subaru drivetrain parts will only withstand a 33 inch tire in offroad (whoops/jumps). It is just not that strong to run a 35 inch tire, and take the impact loads as the tire hits the ground again.

good luck, subaru turbo is the future of offroad.
 

jeff

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The non-STI Subaru 5-speed transmission is junk that Subaru has upgraded for the last 20 years. Back then the Subaru weighed 1500 lbs and had 100hp. The same transmission has been "upgraded" over the years for use in cars weighing over twice as much with almost three times the power. The US spec 6-speed transmission is a major improvement but in stock form it'll still grenade in a truck running with 450hp in front of it. I don't see any reason why you couldn't figure out a way to adapt a different transmission to the 2.5, even a slushbox is possible. I'd skip the expensive Subaru trans route and spend a fraction of the money on an "A-dapta-kit" - even if it were full custom it couldn't be that expensive to have built in comparison to full zoot race gears.

How are you planning on positioning the motor? The 2.5 is a relatively WIDE motor and you'd probably have to mount it high up to clear center mount arms. The Subaru motor width is around 30" inches and for comparison sake a Chevy Big Block (454) is about 27" inches from valve cover to valve cover. Unless you've started mocking this up with measurements in hand it might prove a tougher build than you think.

Aloha
 

xnoregretsx

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The non-STI Subaru 5-speed transmission is junk that Subaru has upgraded for the last 20 years. Back then the Subaru weighed 1500 lbs and had 100hp. The same transmission has been "upgraded" over the years for use in cars weighing over twice as much with almost three times the power. The US spec 6-speed transmission is a major improvement but in stock form it'll still grenade in a truck running with 450hp in front of it. I don't see any reason why you couldn't figure out a way to adapt a different transmission to the 2.5, even a slushbox is possible. I'd skip the expensive Subaru trans route and spend a fraction of the money on an "A-dapta-kit" - even if it were full custom it couldn't be that expensive to have built in comparison to full zoot race gears.

How are you planning on positioning the motor? The 2.5 is a relatively WIDE motor and you'd probably have to mount it high up to clear center mount arms. The Subaru motor width is around 30" inches and for comparison sake a Chevy Big Block (454) is about 27" inches from valve cover to valve cover. Unless you've started mocking this up with measurements in hand it might prove a tougher build than you think.

Aloha

im probably going to machine an adapter plate for a c6 or something.. c6 linked to a full floating 9 inch.. probably currie


as far as positioning i dont think ill have a problem. im building my own bulkead and front halving the truck im sure i can tuck enough of the motor and transmission into the firewall and if not before i start the front ill have to decide on running mid engine v drive .. either way im going with a subaru motor.. and if i can find a 1975 toyota truck frame to start out with ill get it street legal. then i can go blow the doors off some lifted chevys :D
 

jeff

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For the amount of work, its not worth it at all

Ask an "average" person if they think Dezert racing makes good sense. If he wants to throw a Subie motor into a Toyota I say go for it. I think a built 2.5 Subaru powerplant in a Toyota would be a lot of fun. I'd probably just turbo a Toyota motor and make life easy but that's just me. Finding something simple and then figuring out a way to complicate it can be lots of fun!

Aloha
 

josh909

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I loves me some subaru but I don't know if it would be worth the effort. You could get much more power from a normal push rod V-8 for about the same money as a built 257. We were using motors strait from Prodrive and they really put out huge power numbers but they were very high strung and sometimes they liked to let go. Even with a dry sump oiling system which costs bookoo bucks in itself.
 

Pro-Lite Brian

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by fully built do you mean you have the fully inclosed block ?
also are you running a EJ257 motor?


fully built ej257 long block with a port polish and stroker kit naturally aspirated will put down 450... with a garrett gt35r turbo walboroh (spellcheck) fuel pump and pink 850cc sti injectors, machined lightweight pulleys and custom tune by me, along with one off intake/turbo mount and inercooler .. i should be at around 550 on 91 octane ... 6-700 on race fuel and mapping.


when the parts were on my 04 sti with the un-sealed short block i had it tuned back to about 425 hp 415ftlb @3700 rpm 18lbs boost, daily driven throughout the week... beat the hell in the snow, sand, desert, track on the weekends. the stock transmission held up quite well although i did have a stage 3 race clutch installed along with some transmission internals for strength.

if i can come across another matching gt35r turbo or even two slightly smaller turbos
and a set of titanium/aluminum alloy race heads for the ej block i can get 850 streetable/baja ready horsepower


its nice to know im not the only guy on rdc that loves subaru performance


I don't quite no where to start...

You're full of I failed spelling if you think that an aspirated EJ is going to make 450... As for Titanium/ aluminum race heads, again you're high! 850hp. streetable.....high again! I guess it comes down to the old debate over what is streetable...

Yes, 450hp. is possible on pump gas. Keep in mind that there's a huge difference in making an engine live on the street (short bursts), and through power-eating silt or whoops.
 

xnoregretsx

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I don't quite no where to start...

You're full of if you think that an aspirated EJ is going to make 450... As for Titanium/ aluminum race heads, again you're high! 850hp. streetable.....high again! I guess it comes down to the old debate over what is streetable...

Yes, 450hp. is possible on pump gas. Keep in mind that there's a huge difference in making an engine live on the street (short bursts), and through power-eating silt or whoops.



110 octane blueprinted balanced
i was high tho you were right..


and 800 hp is easily attainable with a twin turbo on a 2.5 longblock
 

Tech Tim

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I've built a couple adaptor plates to bolt a Subie in front of a GM Powerglide and Turbo 350 for a couple rock crawler competitors. It'd be easy enough to change the bolt pattern to a C-4.

Wouldn't a C-6 weigh twice as much as the engine and take half the power to run it??? :D

For a quick running Toy truck how about the Lexus 4.0 V8. Very, very smooth running engine and can be built for power. Aluminium block and heads too.... :cool:
 

Dezertpilot

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I don't quite no where to start...

You're full of if you think that an aspirated EJ is going to make 450... As for Titanium/ aluminum race heads, again you're high! 850hp. streetable.....high again! I guess it comes down to the old debate over what is streetable...

Yes, 450hp. is possible on pump gas. Keep in mind that there's a huge difference in making an engine live on the street (short bursts), and through power-eating silt or whoops.

I concur, I just think that you really have no clue what you are getting your self into. I dont think anyone has ever made Ti heads in anything...
 

Pro-Lite Brian

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110 octane blueprinted balanced
i was high tho you were right..


and 800 hp is easily attainable with a twin turbo on a 2.5 longblock

800 is easily attainable with any of a half dozen single turbo set-ups! Nobody would choose to run twins on a 2.5...

As for the 400hp. mark on 110octane, no way!

Doesn't much matter though, as that doesn't even pertain to what you are trying to do. I wish you good luck with your project, as it sounds like a ton of fun!
 
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