Help me with gears!

[Cobain03]

i have my car jacked up, trying to count the gear ratio in my diff. when i chalk my tire and driveshaft, i get 1.5 turns of the driveshaft per 1 tire turn. This is while in drive or in low (c4 auto 3 speed).

what am i doing wrong?

 

[blascrw]

dumb question, but is the tag gone from the rearend?? Do you believe the rearend was changed? if not...look on the door tag.

 

[brianj5600]

The trans has 0 effect on the rear end. If you have an open diff, hold one tire still and watch the other. Or maybe you have a 1.5:1 gear.

 

[Cobain03]

my rear end tag is still on there it reads:

WCZ V9MA
2.78 8 930A


This saying i have a open rear with 2.78 gears. the whole 1.5:1 is throwing me off cause i have never seen a ratio that high. usually 4th gear in a normal setup is a 1:1 ratio.

 

[blascrw]

1.5:1

Dont think I have ever seen that one...

likely a 2.70:1 or very similar gear...but anything is possible.

 

[blascrw]

ratio

welll

the 1:1 ratio you are thinking is the engine to trans output if I recall correctly...
has nothing to do with the rearend...

1 revolution of the crank = 1 revolotion of the output shaft of the transmision.

1:1

 

[Cobain03]

so why arent i seeing AT LEAST one more revolution of the driveshaft?

 

[danny clemens]

Like brianj5600 said hold one wheel still or just jack up one side of the car. Put your car in neutral (making sure it is chocked good). If it is a 2.78 your driveshaft would turn slightly over 2 3/4 revolutions while your tire turns 1 revolution.

 

[blascrw]

tires

your tires will not turn the same as the drive shaft 1:1 ratio...

it should turn the ratio of the rearend...

the way to tell is not with it running and in gear...

jack it up, put in neutral and you should be able to do it...

what are you trying to accomplish, check, or just play and learn?

Nothing wrong with the latter.

 

[Cobain03]

i was trying to figure out my ratio but i got it. found another site that helped me. i have the stockers

 

[stangkid88]

i was trying to figure out my ratio but i got it. found another site that helped me. i have the stockers

2.80:1?

yup, me too

 

[65fastback2+2]

stockers arent bad....mine has an open 3.00 and it'll haul with z28's and SS's....it is all about whats powering it...good thing about stockers is i get about 20mpg

 

[351carlo]

Nothing wrong with stockers.... just a lot that's better with some nice 4.11's!!!!

I had the 3.00 open rear for the longest time. I threw some 4.11's in the rear and the motor came to life. I'm not going below a 3.70 with my new motor, and I'll probably see if I can get away with 4.11's and a 28 inch tire.