on the TBI forum the guys told me it wouldnt take me much more to beat my friend in his 91 mustang GT automatic...is the auto really that slow?

 

The auto's are typically .5 - .8 slower in the 1/4 than a 5 speed with equal mods.

 

thats not that much difference...what you think it would take me to run with him? i plan a new rear with at least 3.42 or better gears soon...definetly posi to

 

My mustang ran 11.80's with a 5-speed. We wanted to put an auto in because we kept blowing up the T-5. After the install we lost a lot, 12.20's and slower. The only thing good about the auto was that you can spray out of the hole, our 60-foot times picked up to 1.52 compared to 1.62 with the T5, but we still lost ET and speed. We converted back to a Tremec and now ran a best of 11.64 @117.

Pete

 

Off the top of my head I think the gear ratios for the AOD in those years was 1st 2.41:1, 1.6:1, 1:1, and 0.74:1 I think thats right. I know the auto rear ends are 3.23 though. In comparison with your Th700r4 you have the advantage there, but for stock engines he's got you there. I have a test of a 91 Mustang GT auto (Motor Trend) that says a 8.0 0-60 time 15.8 1/4 mile time. But on the other hand I have seen early 90s GT autos run high 14s with flows sooo don't underestimate the auto GT but don't over estimate it !

 

my friend has a 91 GT with flowmasters, BBK intake and a 180* stat. his car is quick. if i had to guess, i would say he is around 14.8-15.2. it will take a lot of work to get your LO3 into the 14's but its very possible. im hoping to do the same with my LG4.

 

Gear ratios were 2.40, 1.47, 1.00, 0.67...rearends came standard with 2.73's...3.08's and 3.27's were optional.

For comparison's sake, the T5's had a 3.35 1st gear.

I never got any stock 1/4 mile runs with my 'vert, but my best 1/8th mile time stock was a 10.07.

 

I was close off the top of my head for the gear ratios, thanks for clearing that up Nic.

Yeah the T5's had the 3.35 first but the rest of the gears are the same as the GM version: 1.94,1.34,1.00,0.68 and wasnt the manual tranny rear end standard 3.08?

 

Nope, 2.73's were still standard with 3.08's being optional.

 

BONE STOCK..My AOD Mustang ran a 14.8 @93MPH. To me, that's pretty quick. What kills the AOD i the converter and the rear gearing...which is pretty much set for emmissions and fuel economy. A Nice converter and a set of 3.73's and the AOD cars can haul ***!

My car right now is running 14.4's @ 98MPH with pretty much exhaust mods, gears and pulleys. The motor and transmission or factory stock. I am even having traction probs off the line getting crappy 2.2-2.4 60's. I am installing a Cobra Intake, bigger Throttle Body and other mods too this spring so I am hoping to get lucky and crack a 13.9 with the AOD before I yank it out ad go over to a 5-spd. It's not that I hate the AOD...i just LOVE to drive stick

 

The gears I feel help the autos more, but the stick cars are so much faster. For some reason, the Chevy trannys, in my eyes, seem to be better. That is only comparing the 700-R4 to the AOD. And plus its no fun shifting the auto stang manually. Put it in 1, run up to near redline, put in D, when it shifts pull back into 1, and then into D again. You guys have it easy.