Question about that GM twin turbo L-98
Question about that GM twin turbo L-98
Some of you will probably remember those pictures of the Twin turbo L-98 that GM put together back in the 80's. I believe the pictures came from the Corvette Museum.
Does anyone have any idea what size the turbos were on it?
And would say a pair of T-3's be the equivalent to those?
I am having tourble finding the pics on the net again or else I would of posted them here.
Thanks
Does anyone have any idea what size the turbos were on it?
And would say a pair of T-3's be the equivalent to those?
I am having tourble finding the pics on the net again or else I would of posted them here.
Thanks
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From: Elk Grove Village, IL
Car: 1989 TransAm GTA
Engine: One sweet modified 355 TPI.
Transmission: The kind that shifts....
You can find pics of the TT L98 powered TA out of pontiacs skunk works division below. While I know your looking at the vette, this is a similar setup and engine. 200mph capable with NO aerodynamic mods!
http://www.yearone.com/enthusiast/ar...et/blueta.html
http://www.yearone.com/enthusiast/ar...et/blueta.html
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From: West Hartford, CT
Car: '89 Z28tt
Engine: Dart Little M Twin Turbo
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The pictures posted above are of the Callaway engine in the C4, not the twin turbo Firebird Pontiac built (blatantly copied from HPP mag, and posted here-http://www.skulte.com/other.html).
Andris
Andris
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yeah askulte I saw that one, it still piqued my interest and shows the ability of GM to waste money on R&D then forget about it because they are like a deranged kid on ADD that wont listen to reason.
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Originally posted by askulte
The pictures posted above are of the Callaway engine in the C4
The pictures posted above are of the Callaway engine in the C4
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From: DC Metro Area
Car: 87TA 87Form 71Mach1 93FleetWB 04Cum
It’s not a question of GM being ADD, it was a design exorcise to determine what can be done with the technology. It’s doubtful that they’d ever put something like that in production for both insurance and warranty reasons. It’s the same reason that everyone is so impressed with Chrysler actually building the vipers. It’s not that it’s a great technological feat, but that that amount of HP just opens the door to loads of problems that make it impossible for a large company to actually make a real profit on the car.
FWIW, I thought that you guys were talking about the TT that was GM built that’s in the corvette museum that looks significantly different then both of those pictures…
BTW, all the pics that have been attached so far appear to be using assorted TO4’s…
FWIW, I thought that you guys were talking about the TT that was GM built that’s in the corvette museum that looks significantly different then both of those pictures…
BTW, all the pics that have been attached so far appear to be using assorted TO4’s…
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Car: 1992 B4C 1LE
Engine: Proaction 412, Accel singleplane
Transmission: built 700R4 w/custom converter
Axle/Gears: stock w/later 4th gen torsen pos
I do notice the brackets on that last picture are vette?
Originally posted by B4Ctom1
I do notice the brackets on that last picture are vette?
I do notice the brackets on that last picture are vette?
http://www.corvettearchive.com/images/1985/page4.jpg
here is a crappy pic of it in the car.
Reeves says these GM built TT L-98 vettes burned to the ground.
I read that GM built 14 of these TT vettes, and destroyed them, to go with the LT-5 program instead, giving the R&D for the TT to Callaway.
Originally posted by 83 Crossfire TA
FWIW, I thought that you guys were talking about the TT that was GM built that’s in the corvette museum that looks significantly different then both of those pictures…
FWIW, I thought that you guys were talking about the TT that was GM built that’s in the corvette museum that looks significantly different then both of those pictures…
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From: SE PA, USA
Car: 89 Camaro IROC-Z
Engine: Intercooled Twin Turbo LQ4
Transmission: Tremec TKO 600
The turbos on the GM engines appear to be T3s due to the internal waste-gates. However, they are not the common Garrett T3, maybe a Warner Ishi or IHI. The T4 family of turbos don't have internal wastegates, except for the T3/T4 hybrids (which is based off a T3 anyway).
T3 turbos will fit on top of the valve covers, and below the top of the plenum. My TT TPI in an 89 IROC has no hood clearance issues. Heat is the big issue with the turbos- I think GM also realized that- note all the heatshields and hood louvers on that Vette.
Here is a pic of my engine with modified camaro manifolds- you can sorta see the turbos are below the top of the plenum.
T3 turbos will fit on top of the valve covers, and below the top of the plenum. My TT TPI in an 89 IROC has no hood clearance issues. Heat is the big issue with the turbos- I think GM also realized that- note all the heatshields and hood louvers on that Vette.
Here is a pic of my engine with modified camaro manifolds- you can sorta see the turbos are below the top of the plenum.
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Car: 1984 Corvette
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Note the picture under the engine stand in my previous post ...
I have a picture of that engine in a C4 Corvette somewhere
I have a picture of that engine in a C4 Corvette somewhere
Last edited by JoBy; Jan 24, 2004 at 06:55 PM.
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Engine by Ryan Falconer??!?!? Of the off shore racing Falconer company!!!??? They are the ones that built that V12 for GM that they put in the "snake skinner" a few years back to trounce the then "new" vipers in a C4 body. I can't remeber if it was that one or some other GM stripped out concept car that was stolen by some youngsters and led police on a very long high speed pursuit until it ran out of gas not far from where it was stolen.
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Originally posted by B4Ctom1
Engine by Ryan Falconer??!?!? Of the off shore racing Falconer company!!!??? They are the ones that built that V12 for GM that they put in the "snake skinner" a few years back to trounce the then "new" vipers in a C4 body. I can't remeber if it was that one or some other GM stripped out concept car that was stolen by some youngsters and led police on a very long high speed pursuit until it ran out of gas not far from where it was stolen.
Engine by Ryan Falconer??!?!? Of the off shore racing Falconer company!!!??? They are the ones that built that V12 for GM that they put in the "snake skinner" a few years back to trounce the then "new" vipers in a C4 body. I can't remeber if it was that one or some other GM stripped out concept car that was stolen by some youngsters and led police on a very long high speed pursuit until it ran out of gas not far from where it was stolen.
Ryan Falconer's V12 Corvette (nicknamed Conan the Corvette) was red, with the entire front end extended eight inches so the small block and a half can fit.
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I knew I was remembering it wrong. Im not sure what is crazier, that it just popped into my head, that someone else remembers it, or that someone else remembers it precisely as that
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Originally posted by B4Ctom1
I knew I was remembering it wrong. Im not sure what is crazier, that it just popped into my head, that someone else remembers it, or that someone else remembers it precisely as that
I knew I was remembering it wrong. Im not sure what is crazier, that it just popped into my head, that someone else remembers it, or that someone else remembers it precisely as that

I went to a car show back in the mid-90's, and they had a bunch of experimental Corvette's on display. Some of which were, "Snake Skinner", "Conan", "Big Doggie", "Black Widow" etc....
The reason why I remembered Conan pretty well, is because it made that much of an impression on me. That freaking thing was unbelievable, and it had chrome side-exhaust pipes.
Snake Skinner too. It was a 1989 Corvette, that GM was using to study 'reduced weight' advantages for the Corvette's. But of course, none of these things ever made it into production..... which is typical, especially for GM!
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This pic is without the side chrome exhaust pipes...... but I have a pic from my own mag if anyone is interested in seeing that employs them. 
http://www.vettextc.net/NCM/Conan-V12.jpg

http://www.vettextc.net/NCM/Conan-V12.jpg
Last edited by 406-IROC; Jan 27, 2004 at 12:36 AM.
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