Turbo GN motor in Iroc???

[Turbojunkie]

I just purchased a 90 Iroc 5.7 car and i have been wanting to put a 3.8 turbo motor in it. I know that the heads are different and so were some other things so i figured someone on here might have some experience with this? What other kinds of things will i encounter and can i find these parts? I figured i would get a GN short block that needs rebuilding and start from there. All input is appreciated. (I've posted on many other fbody boards and noone seems to be experienced in this area)
Thanks
BT

 

[Turbojunkie]

Oh yeah. My plan is to build a 500hp street car with the turbo6 engine and drive it daily so A/C is a must!! Also has anyone evvr put the 6spd tranny behind the 3.8T. I know that the turbo spool will become a big concern but has it been done and how did it turn out?
Thanks again
BT

 

[Grumpy]

do a search.....been beat to death many times...lots of guys have done it...Good Luck

 

[trading t/a]

Fly89 did I think. Do a search for his username.....

 

[Turbojunkie]

i did a search for fly89 and came up with nothing anything else.

 

[trading t/a]

You could also check www.thirdgen.org

some of the people suck but the engine swap board is decent

 

[fly89gta]

hi

I bought myself a TTA motor

You want AC? TTA head time or custom AC work

TTA heads=new pistons and TTA headers.

As far as the motor mounts you CAN use the GN mounts, a buddy of mine(TTA850) also did the swap and used GN mounts BUT it makes the engine sit a bit higher, he has a 3'' cowl hood, not sure if there are clearance issues with the stock hood.

 

[70Firebird/TTA]

You might want to reconsider.

The 1990 IROC is the lowest production (last year) IROC (MAP vs MAF) and is considered collectable. The 5.7 was good for sub 6 sec blasts to 60--245hp/345lbs @3400rpm. The "IROC" contract ran out in 90...so Chevy only sold IROCs for 2 months of the year...the rest were converted to 91 Models.

 

[Turbojunkie]

The rarity of this car is of no concern to me. As far as i'm concerned these cars are a dime a dozen and come from the factory SLOW!! the main reason for wanting to do the conversion is so i can have a QUIET 450-500hp street car that will be a sleeper. I have had many 5.0 mustangs and some other 3rd Gen fbodys and i just got tired of the thumping cam and loud exhaust (if the car wasn't to be driven daily then it would be a different story altogether). In doing this i get all the features i want and it would be pretty trick as well. My other option is to either buy a turbo ta which some people would ask over $14k for one that is in the condition of my iroc or put the LT1 and 6spd combo from a z28 in there and i would rather not go that route being that it is more expensive and been done before. I do appreciate all the information that i have recieved so far and keep it up this is a great board where other fellow gearheads can get great specific tech info.
Thanks alot
BT

 

[trading t/a]

By the time you are done it may pay to look into either swapping an LS1/6speed in or rebuild the 5.7 with billet caps a good crank,rods and pistons and boost it. If you are planning on the street nostly few cars have the grunt of a TPI off the line boost it and you'll be amazed at what you'd get...................

 

[fly89gta]

Originally posted by trading t/a
By the time you are done it may pay to look into either swapping an LS1/6speed

A LS1 and a T56 would cost A LOT more $$ than a relatively simple LC2 swap, though it'd be damn cool

 

[Turbojunkie]

Thanks. I think it would be a really nice sleeper car to have. i have been learning alot recently and i don't think it will be all that bad. I have found out that the torque arm bracket for the 200r4 is no longer available but i can get a new torque arm with the 200r4 brackets all ready done for about $330. I know the head info now and the exhaust manifold situation but i have also found a guy locally that could make me some custom headers for it. He makes alot of the exhaust systems in GA for the outlaw 10.5 guys and he does really nice work. I have also just purchased a 92 Z28 "high tail" rear hatch i'm thinking about putting on it when i remove the decals from the car. What kinda restriction do the wheels have as far as fitment is concerned. Also would coverting to coil-overs allow me more room for larger wheels? Thanks alot guys keep the info coming.

 

[trading t/a]

Hey Fly! For what he wants the cost may be similar. By the time you consider a quality rebuild,good turbo,injectors,etc. for the LC2. LS1's have proven to be pretty tough from the factory with mild boost(supercharged). Now if he was to go turbo for the LS1 that would definately skyrocket the price of the swap. But 7 psi on an LS1 should make 450 to the wheels with a good tune.


If he has the mechanical skills to entertain the thought of any swap the cost will be lower than the average joe!

Pete

 

[Turbojunkie]

Yeah i plan on doing all the work myself. The only main reason i was wanting to stay away from the V8's is because i want to keep this car as quiet as possible and all the GN's i have worked with are very quiet at idle until you hit full boost and then thats the sound i want people to remember me by. The 6 spd is not a nessesity, i was just curious if anyone had done it yet with the LC2.

 

[V6QUICK]

Brain you have mail.

 

[Roc87]

It's a fairly straight forward swap. Many have done it. Raced a '94 Z28 A4 yesterday that had head work, headers, exhaust, and a 75 shot of nitrous and he only pulled me by a 1/2 car length (From a roll, around 45 to 110?) I'm sure with my ET streets I could have taken him from a stop. I think we convinced his wife to put in a 3.8 in her '90 Iroc instead of doing an LT1........

 

[Turbojunkie]

I really wanted to say thanks to the people on this board. I found the most information on this board about both GN's and the swap into my iroc that i just wanted to ya'll to know it was greatly appreciated. I'm finishing up my last semester of education and plan on being able to afford the swap by mid-summer. So expect to se more of me when i start the swap and looking for some parts.
Thanks again

Skibum77

 

[Roc87]

You'll be fine if you go with the GN frame pads/motor mounts. That's what I have and it fits fine under the stock hood (even though I have a 4" fiberglass cowl mounted onto the stock hood) my cowl only covers a 15" hole that was cut into the hood when I had a blown 383. And yes , the V6 is faster.

Yeah, you could have a small block or even a big block, but then you'd have ALL THAT NOISE, FOR WHAT!?

If you have any questions, email me anytime, I can't check the board as often as I'd like since I now have a job where I can't get on the 'net