Okay, maybe a couple: Here's the skinny--'86 turbo 3.8 into a 92 bird built strictly for road racing purposes (read: no a/c)

1: Does anyone make aftermarket headers for TTAs? I've heard various rumors that the stock GN manifolds won't work and that they will work but w/ a TTA downpipe. Can anyone confirm this?

2: Numerous past posts state that the GN engines don't run well w/ a manual trans. Too bad, as the plan is to throw in either a T5 or T56 so I have to make it work. Anyone know why a manual wouldn't work well and what I can do about it? Wouldn't a simple swap to a lightweight aluminum flywheel help generate boost?

Thanks guys,

MILT

 

check out www.atrperformance.com

 

1 - TTA headers were never reproduced to my knowledge,so used is the only way to go with that.Fortunatly the headers clean up nicely and can support 650+hp

2 - GN engines wont work well with a manual,especially in drag racing,but nobody ever said it wont work.As long as you stay with a stock or close to stock turbo and intercooler with good tuning spoolup shouldnt be that bad - though it will be compounded by the fact that you'll have to spool the turbo again on every shift.

The downside to keeping the turbo and intercooler small is you'll be limiting your hp to probrobly no more than 400hp if that much.

As far as hooking one up to a manual trans I havent a clue how you'd go about it but if it works out please let us know all the details.

Steve

 

Well, project is still in the "development" phase: I have the car and the drivetrain, but won't be doing the install for quite some time.

I figure a T5 can be hooked up using a bellhousing from a 4th 3.8 motor. A T56 might be able to be installed using the same method as hooking up a 700R4.

I am confused why people continue to claim turbos and manuals don't mix. Many import turbos are hooked up to manuals, especially exotics, and have amazing performance. Is it simply that the engine doesn't like to spin up over 5000rpm? Especially considering that the setup I want will be for road racing, not drag racing. One would think that a manual would be better, as you could hold the engine at an appropriate rpm for maximal boost much better than automatic could.

Also, swapping to a twin turbo setup--using two small turbos vs a larger single would help solve the power vs rpm problem as well.

Does this sound reasonable?

Thanks guys

 

Yes in the import crowd most turbo's are mated to manuals(with the exception of the real quick class racers such as the Venom Supra and Busher Racing Talon who both run Powerglide 2spd).But then in my opinion they all offer lackluster performance alot of which is due to the manual trans.

I am however purely into drag racing and do know there are advantages of a manual in road racing which is where I'm sure these same cars shine.

In the end you'll just have to try it and see if it works - I wish you luck

Steve

 

TTA850 I'm glad you replied!!! You need to get your website back up so I don't need to ask all these questions!

You did a swap using the GN (not TTA) engine correct? The GN headers fit w/o AC and you need to have a custom downpipe fabbed? Any idea on how much, on average, a 3" downpipe might be? I just don't want to go through the hassle of a premature rebuild and transformation into a TTA engine...

Anyhoo, I am still debating what I should do. I have a 200 trans from a GN in great shape that I may start with, but I also have a T5 and T56 setup around as well. Choices, choices, choices.

MILT

 

"I am confused why people continue to claim turbos and manuals don't mix. Many import turbos are hooked up to manuals, especially exotics, and have amazing performance. Is it simply that the engine doesn't like to spin up over 5000rpm? Especially considering that the setup I want will be for road racing, not drag racing. One would think that a manual would be better, as you could hold the engine at an appropriate rpm for maximal boost much better than automatic could. "

most turbo and supercharger designs require the engine to be under load to produce boost. That's why an auto will give better performance. You can stall it up for the launch, and boost will remain smooth even when you shift because you don't have to let off the throttle. I don't know exactly WHY it needs to be under load, but it does

Next time you're with someone that has a boosted car (except roots type blower) have them gun it at idle. The boost guage won't raise at all.

So it will work, but the auto will just work more efficiently.

Hope that helps some,
Matt

 

onebinky is right,and I do know why it's just hard for me to explain and hard to understand untill you have some real world experience with turbocharged cars.

I started off with and engine/trans out of an 43K mile 87 GN.Actually I had the whole car,it was a friends and I bought what was left after it was recovered stolen(they took everything but the motor/trans/rear).

I did however convert the motor over to TTA style heads and had custom JE Pistons made for the motor(JE doesnt make an off the shelf replacement for the TTA).Also I found a used set of headers from somewhere in Texas and have come across others so they are out there.After that ATR makes a new crossover pipe for the TTA and several very nice downpipes(I already had a Terry Houston 3").I also used ATR's 3" cat back exhaust which I highly reccomend on a turbo car as turbo's require a very different style of muffler(AKA definatly not Flowmaster or anything like it)to work at it's best which is what ATR specializes in.

I understand what you mean about not wanting to prematurely rebuild the engine and can tell you that with a custom downpipe and no a/c a stock GN motor with GN headers will fit though I dont know hoe much a custom downpipe will run you.

Steve

 

I understand the load vs. boost thing now (I simply don't want to believe it ). I may still have to try out the manual trans just so I can see it run crappy for myself...

TTA850: IIRC, did you use a PA Racing tubular K-member? I thought I remember seeing that on your website some time back.

MILT

 

yes he did. It's a really nice piece.

Steve already brought up the points about the manual/turbo 3.8 combo. I'm surprised some of the self proclaimed turbo experts having dropped their opinions on the matter yet(do a search with my name to understand what I'm talking about, many arguements have surfaced on the V6 board, it wasn't pretty lol).

You can try it, not sure how it'd work out for road racing but drag racing it'd suck. See the import guys run smaller turbos and their engines can rev a lot higher...you don't have to rev the 3.8 over 5500...unless of course you want to drive over your crank

 

So if I'm understanding this right, the turbo/stick thing works well with the imports becuase the combo of the high RPM's and small turbo. So, when you get off the throttle and get back on it you don't have to wait for it to spool back up. As soon as you punch it your back in the boost.

If that's the case, could you build the motor to rev a little higher and use 2 smaller turbo's to work with the larger CI engine? That way he'd still be able to use his stick

 

That's exactly what I'm thinking...

Plus, go with as parts as light as possible/practical (e.g. flywheel, driveshaft) to help improve the acceleration of the engine into higher rpm/boost ranges. Every little bit counts...

Well, thanks so far guys. I will have to do some more research, but in the end I am going to have to try it. I will, however, keep the 200 trans around...just in case...

MILT

 

The 3.8 isn't built to rev high, case closed. Also to do a TT setup you better have deep pockets. It's impractical to do a stick swap with that motor. I know of two people that actually did the swap and they said they wouldn't do it again even if they had to

 

Stop telling me this...you're ruining my plans!!!!!

Anyways, I appreciate the input...maybe I will just use the darn auto trans.

MILT

 

Don't get me wrong, I myself would love to do a swap like that for the wow factor...but build yourself a solid auto, manual valve body and a good quality converter you'll still have the fun factor

 

I did some more research on turbobuick.com and decided that unless I win the powerball, I'll stick with the 200-4R.

MILT

 

Let us know how it all works out, this has me interested in maybe doing a turbo 6 instead of a built 350. Definately a different route

 

well considering I already did the swap I can tell you how it turns out lol

 

I did the swap too and can tell a whole different story

Most of mine is in my sig though

Steve

 

blah blah blah blah blah, always have to steal the show don't you?? LOL

Steve I think the guys talked to me into a roller cam conversion

Did you get my email about that wiring harness?

 

you guys wouldn't happen to have a website outlining what you did, would you?

If I ended up doing this, I'd probably go the junkyard route with thunderbird T-3's and by welding a few big volvo intercooler cores together.

Matt

 

no,not yet but shoot me an IM if you want, I can answer any questions you might have.

Also there is NO need for two turbos, you'd be making more work for yourself. Two turbos DOES NOT=more power.

My AIM name is ClarkeMustGoNow