I have 3:73's in my 91 gt aod and i recently took it to the drags and ran a consistant 14.97 at like 93mph. My question is is that i feel the car ran out of gear down the track. I was crossing the line in the high 4k range but the car didnt seem to pull very much once i got down the track. What are you guys running when you cross the line? Everyone says to go with the 3:73's and 4:10 but after going to the races i feel i would be better off with 3:55's or 3:27's? Take in consideration my car is pretty much stock besides the gears and a cobra intake along with 70mm tb and mass air. Should my car with these gears be going faster than this?
People running 3:73 or higher gears
- Thread starter Drago
- Start date
Changing gears won't help. Your pretty much stock, and that's half the problem. I don't know the condition of the engine but I can say that even in really good condition the engine stops making any more power after 4000-4800 rpm. To make a long story short, the heads are choking you. What exaust setup do you have? Even with stock exaust doing heads would make a day/night difference. If you have the cash, I would get some AFR's, and if the budget is too small for the AFR's then I would look into some Thumper's which cost about half that of AFR's. Another rought is some junk yard GT40's which don't flow quite as well but you probally can score for about half of that and can be ported later.
88stangmangt
Active Member
4.10 with a aod is the way to go you need the balls and you shouldnt be running outta gear at that trap speed either.
willys1
Active Member
I have a 93lx with a stock motor and bolt ons,2800 stall,shift kit.When I had 373's,I ran a 14.3. Then I got 410's,and went 14.5!! I know what you mean about dying out around 45--5000rpm.3rd gear s@cks in the aod.
timewarped1972
Member
DRAGO; thats probably ball park. alot of research on average 1/4 mile times showed me stock 91 ish gt'swith the doa tranny ran mid to high 15's. that may have been driving it nice, but, i'd say they were probably in that area........my next mod ( after a friggin radiator ) will be a shift kit, and after that i dunno........i hate to buy a manifold when the heads are right there, seems like i should do it all at one time, not sure. heads are the way to go though, my 65 302 has ported and bigger valved iron heads and makes a major diff over stockers. there's so many types of heads though, so we shall see.
havent had mine to the track but i'd guess it runs between 14.8 and 15.2. your gears are ok, 4.10's wont help right now if your already running outa breath in the top end. 3.73's are good all round gears i certainly would.nt put stockers back in. lots of people say anything bigger than a 65 mm tb on a stock engine can cause problems too........all you need are some heads and you'll be rippin.
havent had mine to the track but i'd guess it runs between 14.8 and 15.2. your gears are ok, 4.10's wont help right now if your already running outa breath in the top end. 3.73's are good all round gears i certainly would.nt put stockers back in. lots of people say anything bigger than a 65 mm tb on a stock engine can cause problems too........all you need are some heads and you'll be rippin.
rd
Founding Member
What is probably killing your et most is the stock torque converter. Overall, your mph shows some good power. The stock converter is keeping the engine below the power range too long in low gear.
4.10 gears will help some, but a converter would be the biggest improvement, after which you will need stickier tires.
I went down this road with my 79. With the stock converter, I was stuck in the high 15's but always at 90 to 92 mph. Changing to the first level up, a 2000 rpm stall, cut it by 5 tenths, but I still could not get it out of the low 15's. Best was 15.37 with 4.10 gears.
I put that engine in my 82, and with a 3200 rpm converter and the same 4.10 axle, and now Drag Radials, it now runs low 13's on the motor.
4.10 gears will help some, but a converter would be the biggest improvement, after which you will need stickier tires.
I went down this road with my 79. With the stock converter, I was stuck in the high 15's but always at 90 to 92 mph. Changing to the first level up, a 2000 rpm stall, cut it by 5 tenths, but I still could not get it out of the low 15's. Best was 15.37 with 4.10 gears.
I put that engine in my 82, and with a 3200 rpm converter and the same 4.10 axle, and now Drag Radials, it now runs low 13's on the motor.
