N\A or Turbo

[decke48]

so i was thinking with my new car i thought i would make a nasty N/A engine. little bored with the little turbo lag, from my past two subarus.
so ill make two list and tell me your opinon for which i should do.

N/A
Oem sti block.
cosworth big port heads, or ported oem sti heads
briancrower 83mm stroker with forged rods making it 2.71L
comes with 102mm turbo piston (not used for this)
forgeds DOHC RS pistons 11.2:1
278/274 cam maybe cosworth
cosworth valve springs
cosworth high flow oil pump
sti pink injectors?
perrin fuel rail
255lph or high fuel pump
magnas sti intake
jdm sti throttle body
cosworth .78mm head gasket
cosworth bearings
headers, 3" exhaust no cat, straight flow muffler
v5/6 sti DCCD tranny and r180 diff
other things i probally forgot


or a stock jdm v5/6 sti drivetrain maybe some mods

[AJM]

I'd honestly think that 2.5 in piping might be better ,and get the intake and throttle body ported too...

Looks like fun!

[Mr. Sociable]

I really think N/A Subarus are neglected (and for a decent reason...hard to pass up the turbo EJ's) but would love to see this and the numbers put out.

[StatGSR]

u forgot engine managment. frankly your guna be spending gobs of money for little power.

if your lookin for some decent na power, look into eg33 swaps. there is a guy here in mn with one in his GC, its basicly a sti killer out of the box. and crap if u tossed a little turbo on that, you sure wouldnt have any turbo lag either.

heres a nice h6 swap i found on nabisco...
http://forums.nasioc.com/forums/showthread.php?t=911106

[decke48]

ok then how bout a turbo h6 with ecutune stage 2 ecu, there forged pistion 8.5:1, connecting rods, cams 9mm intake 9.3mm exhaust, and bearings. a hks gt28xx 71.1mm to gt34xx 82mm turbo. custom exhaust. other stuff

i dont know anything about the egs do the ej tranny bolt up to them?

[StatGSR]

yea an eg is a ej with 2 extra cylinders, and yes it will bolt up to the tranny.

[Jedi Taxi]

Or, if your good with your hands, have the tools, have the knowledge. you can build an amazing ITB set for it, and make great power while being N/A. after doing alittle math, you would need 40mm throttlebodies if you wanted a strong Helmholtz resonace effect at 3500rpm, and at least 4" of runner length (assuming port depth is 1" and that the throttlebody is 1" with a 1" velocity stack).

Or you can look at a SOHC dodge 3.5L V6 from an 1st gen intrepid. It utilizes twin 48mm throttle bodies. Basically, make the flanges to mate to the block, weld on some proper length runners, a decent plenum and use two throttle bodies. from their, the rest is all but easy.

either way you go, you would need to convert it to a MAP system, make sure all the proper sensors are their, (IAT, TPS, MAP, MTS,...etc.) Block off the EGR so you don't have to mess with it. (just find the right resistor to tell the comp that its working right.) pipe all the fuel lines to work with the new manifolds, and your almost done. from their, you can decide to either keep the turbo, and still use the ITB or DTB, or just decide to keep it N/A. Though, it you do use the turbo still, and the ITBs, you will notice alot better throttle responce and I'm willing to bet, less turbo lag.

(edited for redoing the math for the ITBs to work with 40mm throttles)

[decke48]

well i think i might just go with the N/A
hks f-con v pro piggy-back
carrillo k1 83mm crank
injen rd cold air intake
toga high flow oil pump
techwork 11.2:1 (91oct) would like to do 12.5:1 but to high of octane level
techwork stage 3 DOHC i .420 249* e .420 241*
techwork springs
techwork rods
magnis long runner intake
70mm sti throttle
+1mm valves
sti pinks 565 or 600
walbro 285lph pump
oem sti block
arp mains and heads
centerforce clutch
v5/6 drivetrain

[decke48]

hmm should i do a 3.3 build so i can run a crazy 30lbs of boost :grin:

[Airgne]

3.3 all the way all motor. i think it would be a killer and diff than all the turbos out there now.

me? I'd have not sold that 22B and started modding the hell outta that thing, talk about the perfect place to start....

[decke48]

well would you pass up the $67000.

[Huffer]

^^ probably not, but then I wouldn't get an ego walk from doing it either. :roll:

well would you pass up the $67000.

yeah, in a heartbeat

money comes and goes, but finding a car that you love, in good condition....thats priceless


if you're wanting BIG power and money isn't an issue, and you still want a N/A engine, check out xccelleration.com, they specialize in expencive motors

[PA-Outback2000]

with full exhaust, intake, pulley, cams, and engine management u can see around 240HP on a N/A 2.5. this is the point where most turbo it if they already haven't. i have been talking to a guy who did a high comp build with everything and got 280HP. he would do an N/A again, but not to that level if he did. the AVO kit adds around 100HP to whatever u have done to the car already.