#1:
86 Trans Am - LB9, automatic, 2.77 gears, non-WS6

#2:
88 Trans Am - LB9, 5 speed, 3.08 gears, WS6

I'm guessing car #1 would run 0-60 in about 8 flat, and run the 1/4 mile in about 16 flat. I think car #2 would shave about 1 full second off both times. Does that sound about right? I don't have any period road tests of either car...all the LB9 sticks in tests have 3.45 gears.

 

Theoretically, the later 5spd has less weight, and a better cam... The 86 LB9 is a total dog, about on an even field with the low output 305's. 16 flat is probably about right. The 5spd car is probably closer to a 15 second car, give or take a tenth or two.

Honestly I don't even consider pre-89 thirdgens as being all that great performance wise. MAF TPI peaked in 89, and the speed density TPI cars seem to work even better. Given the choice, I'll always angle for the newest thirdgen I can find.

 

What's the differences between 88 and 89 for TPI? Obviously, dual cats were available in 89...otherwise, were there really any differences?

After the GTA I'd found turned out to be nothing like I thought, I've gotten some very nice, large photos of car #2 and am considering going to see it. Seems to me like it'd be a significant performance increase over my 86. The 86 is going to the body shop for a repaint this week...I know its kind of a slug, but I only use it around town and some brief highway runs. Its got enough torque to be fun...down the road I will probably throw a cam and some 3.27s in it, unless I feel a massive need to leave it 100% stock.

Its kind of funny that I sold my red, 5 speed, 305 t-top Camaro and am now looking at a red, 5 speed, 305 t-top Trans Am I simply don't see many LB9 sticks, and this looks like a nice one....

 

Performance wise, yes, the dual cats are an improvement for L98's and LB9/M5's in 89. And 89's also use the better, aluminum caliper rear discs.

 

The Cam was the same for 1988 & 1989, It really would be the hottest cam far as numbers from 1987-1992. There was a few minor changes from 1988 & 1989, some of them were cosmetic, like the black painted cowl area went away, the Base Firebird and Formula got black airdams instead of painted, I also think there was some other things that made the cars slightly lighter in 1989, The N10 Dual Cats was made available in 1989, and the 9th injector went away...

John