How can i verify what gear my car has?

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
Nov 11, 2003
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Northern KY
Aside from pulling out the gears, how can you measure and find out exactly what gear ratio you've got, like if you didnt install the gear yourself? A friend of mine just installed 3.73s in his car, and i swear it feels just like my car which is supposed to have 4.10s, so since i didnt install them myself, i'm starting to wonder.

I've heard something about jacking the back up and spinning tires but it's pretty cloudy...any tips?
 
Yeah, I'd would jack up the back, put the car in neutral, and spin the tires.
First make a mark on the driveshaft, or just watch it. Count how many revolutions the tires make to get one revolution out of the driveshaft. Make sure both tires are spinning at the same rate. This should not be a problem with a 5.0 that has a factory traclok.
This is the easiest method I know of.
Also, what mods does your car have compared to your friends car. Might make the difference.
 
yeah...what he said.....I'd take some chalk and mark the inside of the tire and spin the driveshaft by hand and watch as the tick mark goes by.....if the tick mark goes by 4+ times to your one revolution of the driveshaft then you have 4.10s
 
mark the driveshaft, and spin the tire one full rotation and count how many times the driveshaft turns over. If it turns over 3 1/2 times then you have 3.55s, if it turns over 3 3/4 times then you have 3.73 gears, and 4 times for 4.10s. Hope this helps.

Matt
 
Boy that's a lot more common sense than i would have guessed it....lol I feel kinda stupid now... :D

As far as mods go, his motor is just as stock as mine, except it's a '90s motor vs. my '85. His car is an '86 coupe so it's nearly identical to mine except for the EFI. I know my car is faster than his, but the torque/takeoff part feels the same.