I'm just wondering if GM changed the TPI runners at all through the years they were fitted to the thirdgens? If they did I presume any runner from any year will be interchangable with any plennum/base from any car/year?

Thanks for the help

Rob

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1987 IROC-Z Auto (LB9)
Black/grey interior with the stance of a streetfighter
I like to think of her as Arnold Schwartzeneger in a dinner suit

Mods
Custom exhaust. 4 Inch pipe from the headders all the way back to a single muffler at the rear. No Cat. K&Ns, AFPR and Air foil.

Future mods:
Cam change
New torque converter
New heads (maybe corvette L98)
Strut brace
Sub frame connectors
Ram Air

Current G-Tech times
0-60mph 6.26 seconds
1/4 14.74@100.2mph

 

85-88 have cold start injector provision, (driver's side), 89-92 do not. I don't think there are any other differences. Anyone want to add to that?

I know there were 3 different stock plenums used between 85-92, 85-89 didn't have the port for the MAP sensor, 90-92 did, and inbetween there someplace the ports for the EGR were a little bit different. Someone posted a pic a while back of the 3 different plenums.... maybe they can post it again.


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Kevin Irving
85 Trans Am WS-6, 305 TPI, custom burned '86 PROM with '87 "165"ECM, Accel Supercoil & 8.8 Wires, Rapidfire #2 @ .055", MSD 6AL, 1.6:1 Roller tipped rockers, Homemade AFPR, K&N cone, no airbox, Aluminum Driveshaft, Wonderbar, TB Coolant Bypass, Ported Plenum, Descreened MAF, Syclone Fuel Pump, JET Airfoil, Mobil 1 synth in all but transmission.

15.556 @ 86.65mph, Nov 10, 2000.... I know it sucks.. but it will get better!

http://www.geocities.com/transam85tpi/

Member - The Tidewater Trans Am Club, Norfolk VA http://www.geocities.com/ttacva/

[This message has been edited by Kevin Irving (edited May 07, 2001).]

 

Are you sure about differences in EGR? If i was gonna identify 3 plenums, it'd be the MAF plenum, MAP plenum, and the vette plenum (rough cast finish in late 92s like mine.)
...ed

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Ed Maher - Moderator @ The Carb Board
92 Z28 Convertible - Quasar blue / Tan top
LB9 4L60 GU2 G80 - stock, soon to be sleeper
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- Definitely prototypes, high powered mutants of some kind. Too weird to live, too cool to die

 

Ed,

The pictures showed a smaller or shorter EGR passage in one of the plenums... I would kill for that pic right now. I don't think there was any difference in functionality though, but the pics were taken of the bottoms of the plenums where the difference was plain as day.

 

85-88 is one style, 89-92 is the other style. They're not interchangeable.

85-88 plenums are the same. 89 is its own style, and 90-92 is the third style.



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West Coast GM Shootout 2001!
1991 Camaro Z28
5.7L 5-Speed (originally 305)
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Southern California
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