DO I HAVE GEARS? (anyone running 3.73's help me)

SAYNOTORICE

New Member
Aug 21, 2003
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Massachusetts
ok so i have been told by others that my car is geared (3.73's) the previous owner (2nd) said no, and i have no contact with the first one....the car was unmoded when i bought it except for flowies, it is an m code axle car....my friend who had a 90 LX 5.0 had 3.73's and he says his car reved the same as mine...i remember being in his car and it felt alot more powerful than mine.....i am running 3000 rpm's at 85mph....i have been told this is too high to be a stock ratio....another indicator is that everyone with stock 2.73's says that they cant break lose by just mashing it in 1st, but in my car, if i mash it in 1st i dont go anywhere...finally i raced my friends lt1 firebird from a roll and i put a car length on him in 2nd gear (he beat me in the end though)...his car has full exhaust, aluminum drive shaft, 6 speed and 3.73's.....i was happy about how my car performed...but i didnt think it was normal for my stock, ungeared 5.0 to get a jump on a geared 350 lt1 from a roll...shouldnt he have smoked me right away with him being geared???.....do you guy think i am geared, what do other guys running 3.73's rev at when at 85...and finally, if you guys cant diagnose me, how do i count the axle spins to determine exactly what ratio i have....anyone who helps rules :hail2: :hail2: :hail2: :hail2: :hail2:
 
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I had the same question when I bought my '88. Just jack up the car and lay under it. Mark the axle and have someone spin the tire. Count how many times the axle spins and divide the axle rotations by the tire rotations (Might be tire rotations divided by axle rotations.. It's easy to figure out either way). Try to spin the tire at least 5 times for a more accurate reading... worked for me.
 
3.73:1 Should be 3.73 turns of the driveshaft is one turn of the tire. My speedo is way off from my gear install so I'm not sure about speed. But my dyno sheet says I was doing 60mph in 4th gear at 3400 rpms. Hope this helps. No dyno time in 5th gear..... :D
 
3000rpm's at about 85mph sounds like 3.73's, I have them and that is where I am, of course speedo accurasy has to do with it, but generally speaking.

To find out, lift vehicle and when in neutral, turn the shaft and cound how many times it takes to make the wheel spin around one full turn. If it turns about 3 and 3/4ths turns to one wheel roll, you have 3.73's, 3 1/2 turns, 3.55's, you can figure it you.
 
cool, you guys rule :nice: sounds easy enough...anyone think they can diagnose me with the way i ran with that lt1???? i was ahead of him by a car length after 2nd gear, and we started from a roll....he passed me at 85 when i was shifting from 3rd to fourth...fox saleen is that about where you shift from 3rd to fourth?????
 
cool, you guys rule :nice: sounds easy enough...anyone think they can diagnose me with the way i ran with that lt1???? i was ahead of him by a car length after 2nd gear, and we started from a roll....he passed me at 85 when i was shifting from 3rd to fourth...fox saleen or 90stangGt is that about where you guys shift from 3rd to fourth?????
 
SAYNOTORICE said:
fox saleen or 90stangGt is that about where you guys shift from 3rd to fourth?????

I shift at 5200 when I'm trying to go fast. Not sure what speed that is. 5200 rpms in 4th gear is 92mph, or so the dyno says.

I can't tell you how you did against that lt1. Some people just can't drive, others drive slow azz GM's and get stomped.
 
This sounds dumb but I tried to check my gear ratio the other day with the way you guys just explained. I jacked up the rear with the car in neutral and the e brake off. The rear tire would not turn no matter what. Niether would the other rear tire. How could this be? The car rolls out of the garage in neutral if pushed, why couln't I turn the rear tires?
 
nah kid can drive well and we went from a roll so skill really didnt matter....with his 350 and 3.73's and being in 2nd gear i feel he shoulda stomped me if i was running 2.73's...but i put like a car on him in 2nd....does anyone else agree with that...i really dont feel like waiting a weeek till i go home to be able to check out my car....someone has to be able to tell whether or not its possible to have stock gears and put a car on an lt1 after 2nd goin from a roll
 
You cant tell by racing someone. Ive cut just as good 60 foots as the 3.73 guys with my 3.55's. With 3.73s your speedo is NOT accurate. Also the stock tachs are known to vary from car to car. The way to know is to count the driveshaft rotations or tear into the rear end.
 
I believe both rear tires must be off of the ground at the same time or else it won't work, but I could be wrong. I posted this already in the original thread about the gears but I'll say it again, those are NOT 2.73's, more than likely they are 3.73's. Also, I do have 2.73's for now and can break the tires loose pretty easily by just standing on it in first gear ;) .
 
werd, i guess i will be counting when i go home...i know you cant tell by racing someone, but from my knowledge of stangs and f-bodies, if i saw the race as a spectator i wouldnt believe that the stang had the stock ratio...there is no way a stock 5.0 should put a car length on a geared 350 lt1 from a roll, the lt1 should juust romp it...im hoping i dont have 3.73's even though it would be like a free mod, i was just hoping that when i put gears in i would really love it...ah well :shrug:
 
4.10's in a daily driven 5 speed? Like I said, I have 3.73's in my car which is a 5 speed and I think it might be too much gearing. Once I get more mods I will probably go to a 3.55 or even a 3.27. Keep in mind this a track car not a drag car. If you can handle the extra RPMs in 5th gear go for it, but I can't put down any power in first gear with these 3.73's.

But anyway, I don't think you have 3.73's... if you did you wouldn't want 4.10's. First gear basically doesn't exist.

Now... 4.10's in a daily driven modular motor with a 5 speed is a different story. Mod motors love that gear.