How to tell if they're 3.73s

[iwannarace67]

So a friend of mine just went out and bought a fox body over the weekend which is cool. It's a 89 5-speed with supposedly a 3.73 gear. Now the car accelerates like a bat out of hell but it doesn't quite feel like a 3.73. Now how can I tell if the rear is really 3.73? Count the teeth on the gears?

 

[ironheart1]

I believe the following will work.

Get the rear of the car up on jackstands, take it out of gear and make sure the Ebrake is off. Make a small mark on your driveshaft and have someone turn the drive tire in a complete rotation... Count the number of times the driveshaft goes around. If it goes around about 3 and a half times, it's 3.55s, about 3 and 3/4 times, 3.73s.. Just over 4 times, 4.10s, etc.

 

[cjman15]

thanks, i was wonderin how to do that too

 

[QDRHRSE]

I believe the following will work.

Get the rear of the car up on jackstands, take it out of gear and make sure the Ebrake is off. Make a small mark on your driveshaft and have someone turn the drive tire in a complete rotation... Count the number of times the driveshaft goes around. If it goes around about 3 and a half times, it's 3.55s, about 3 and 3/4 times, 3.73s.. Just over 4 times, 4.10s, etc.

Yep. This is definitely a good way to check.

 

[SuperStang83]

Yep, that's the easiest way to do it!

 

[iwannarace67]

yup it works...they are 3.73s.

 

[Euphoric306]

i was gonna suggest that but didnt want to feel like an idiot if it wouldnt work but i see now it does, thanks

 

[t69r00p69]

you could have just tok the bolts of the pumpkin and counted the teeth on the gears but the other way is seems alittle easier

 

[ironheart1]

Yeah, I have to do this myself still. I was actually told 4.10s, I am at 2600RPM at about 70, and all the math works out, including the SOTP feeling. But I never confirmed it for sure.