frankenmotor

Heads, valves, pistons, rods, crankshaft, etc...

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siouxbe
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frankenmotor

Post by siouxbe »

I'd like to get a USDM STi shortblock and put it in underneath my 2.2l NA heads and still run 85 or 87 octane pump gas. Using the STi 2.5l headgaskets.
Is this realistic?
Does anyone KNOW what the compression ratio would be???
1991 Subaru Legacy BJ 2.2L/2.5LSTi Block Hybrid N/A w/ over 250,000 miles! 1992 Yamaha Seca II 2004 Dyna Super Glide My other car is a Go Kart Redhair...Black Leather...My favourite colour schemes. If it's not Scottish...it's Crap!
siouxbe
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Post by siouxbe »

does anyone know the deck height and dish of a USDM STi short block???
1991 Subaru Legacy BJ 2.2L/2.5LSTi Block Hybrid N/A w/ over 250,000 miles! 1992 Yamaha Seca II 2004 Dyna Super Glide My other car is a Go Kart Redhair...Black Leather...My favourite colour schemes. If it's not Scottish...it's Crap!
siouxbe
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FrankenMotor 2.2l heads on 2.5l shortblock

Post by siouxbe »

I've calculated the compression ratio to be approx. 11:1
with 2.2l heads on a 2.5l short block w/ stock gaskets.
Anyone have experience having done this set-up?
If so, what octane fuel are you using?
What is your power increase?
1991 Subaru Legacy BJ 2.2L/2.5LSTi Block Hybrid N/A w/ over 250,000 miles! 1992 Yamaha Seca II 2004 Dyna Super Glide My other car is a Go Kart Redhair...Black Leather...My favourite colour schemes. If it's not Scottish...it's Crap!
entirelyturbo
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Post by entirelyturbo »

Since Kelley has managed to put EJ257 heads on an EJ22T, it must then be possible to put EJ22 heads on an EJ257.

However, if you calculated the new compression ratio at 11:1, then there's NO way you'd still be able to run 87 octane gas.
"Der Wahnsinn ist nur eine schmale Brücke/die Ufer sind Vernunft und Trieb"

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206er
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Post by 206er »

altitude my friend.
I have run a tank of half 85 half 91 up here with no noises. I just run premium anyway.
with the stock exhaust I hated it but now with something that flows ok it really woke up. next I'm getting some cams.
put some cams in the motor when you originally build the motor, wish I had.
its still not going to be a fast car in the scheme of things, mine weighs like 3200 or something but it is a good balance of features, its a good motor. lots of low end. it must haul ass at sea level.
and I know Ive said it before, but I dream of throwing this motor in an ea81 hatch, it would scream! if you could keep transmissions in it.
Last edited by 206er on Thu Oct 12, 2006 1:25 am, edited 1 time in total.
1994 Touring Wagon: ruby mica, 5mt swapped
rally370
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Post by rally370 »

You might find something of use in this thread


http://forums.nasioc.com/forums/archive ... 31527.html
Cheers

Chris

Rally Legacy AWD #370 gone! Rally Suzuki swift GTI N1 #370 parted out. Now Mini Cooper #370 with STI suspension in Costa Rica
Matt Monson
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Post by Matt Monson »

Siouxbie is already running handmedown Delta cams from teh Ghetto Garage...

Plus, what 206er said. Up here at 5000ft, we get to cheat. 11:1 CR will do all right on 97 octane, though it will be most happiest on a blend of 91 and 87...
1974 Porsche 914 Cam Am Limted Edition AKA the Bumble Bee
1973 Porsche 914 2.0 l -Suby swap pending
1968 Porsche 911t survivor 47k original miles
2000 2.5RS daily driver.
1999 2.5RS w/ 50+ extra whp
Suby Hai!
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