Help me with gears!

Cobain03

Active Member

Aug 27, 2003

996

0

36

Lexington, Ky

Jul 23, 2006

#1

• Jul 23, 2006

• #1

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

Member

Aug 19, 2004

191

1

16

Opelika, AL

Jul 23, 2006

#2

• Jul 23, 2006

• #2

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

Active Member

Sep 19, 2003

1,964

2

39

Middle TN

Jul 23, 2006

#3

• Jul 23, 2006

• #3

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

Active Member

Aug 27, 2003

996

0

36

Lexington, Ky

Jul 23, 2006

#4

• Jul 23, 2006

• #4

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

Member

Aug 19, 2004

191

1

16

Opelika, AL

Jul 23, 2006

#5

• Jul 23, 2006

• #5

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

Member

Aug 19, 2004

191

1

16

Opelika, AL

Jul 23, 2006

#6

• Jul 23, 2006

• #6

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

Active Member

Aug 27, 2003

996

0

36

Lexington, Ky

Jul 23, 2006

#7

• Jul 23, 2006

• #7

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

 

D

danny clemens

Member

May 4, 2005

728

0

16

Jul 23, 2006

#8

• Jul 23, 2006

• #8

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

Member

Aug 19, 2004

191

1

16

Opelika, AL

Jul 23, 2006

#9

• Jul 23, 2006

• #9

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

Active Member

Aug 27, 2003

996

0

36

Lexington, Ky

Jul 23, 2006

#10

• Jul 23, 2006

• #10

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

 

stangkid88

New Member

Nov 11, 2005

112

0

0

Seattle area

Jul 24, 2006

#11

• Jul 24, 2006

• #11

Cobain03 said:

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

Click to expand...

2.80:1?

yup, me too

 

65fastback2+2

New Member

Aug 4, 2003

1,229

0

0

Louisville, KY

Jul 24, 2006

#12

• Jul 24, 2006

• #12

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

 

3

351carlo

New Member

Mar 9, 2004

267

0

0

Philadelphia

Jul 24, 2006

#13

• Jul 24, 2006

• #13

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.