rear ratio

69-Sguy · 11-18-2007, 01:34 PM

Odd question, maybe someone could help. I was trying to determine what gears I have (because I've got a real dog out the hole), so I used the tried and true method of jacking up the rear, marking both the driveshaft and the power tire (right rear). I spun the driveshaft by hand until (with help watching) I had the tire rotate 10 times, all the while counting my drivshaft rotations. It turned out to be 14 driveshaft rotations to 10 tire rotations. Could this be right, a 1.4:1 gearset? Anyone ever heard of this? It's a 69 Cutlass convert, and I'm almost positive the rear is origional. Did they even make a rear this low? If so, I guess I now know why I have no acceleration from a standstill. Thanks and Happy Holidays.

Redog · 11-18-2007, 02:36 PM

Is there an RPO code sheet on the trunk lid?

Probably a 2 series gear. I would guess 2.56 or 2.73

The code should be a GU code, and G80 which is a posi

88 coupe · 11-18-2007, 08:54 PM

Quote:

Originally Posted by 69-Sguy

........ 14 driveshaft rotations to 10 tire rotations ........

If you had turned both tires (like when the car moves) you would have counted 28 driveshaft revs, or 28:1 = 2.8:1. You could have turned the single tire 20 (10 for each wheel) times, to get 28:10 = 2.8:1.

From where you are now, it's easier to multiply your 14 revs, by 2 to compensate for the missing 14 turns = 2.8:10 = 2.8:1.

Quote:

........ Did they even make a rear this low? ........

In this context, 1.4:1 is a high gear. 6:1 is a low gear.

Norm

sexycutlass69 · 11-19-2007, 07:56 AM

I'll hit you up on your PM!

11-18-2007, 01:34 PM	#1 (permalink)
69-Sguy Junior Member Join Date: Dec 2006 Posts: 14	rear ratio Odd question, maybe someone could help. I was trying to determine what gears I have (because I've got a real dog out the hole), so I used the tried and true method of jacking up the rear, marking both the driveshaft and the power tire (right rear). I spun the driveshaft by hand until (with help watching) I had the tire rotate 10 times, all the while counting my drivshaft rotations. It turned out to be 14 driveshaft rotations to 10 tire rotations. Could this be right, a 1.4:1 gearset? Anyone ever heard of this? It's a 69 Cutlass convert, and I'm almost positive the rear is origional. Did they even make a rear this low? If so, I guess I now know why I have no acceleration from a standstill. Thanks and Happy Holidays. __________________ Go topless and feel the breeze

11-19-2007, 07:56 AM	#4 (permalink)
sexycutlass69 Junior Member Join Date: Oct 2007 Location: San Diego Posts: 13	I'll hit you up on your PM! __________________ LIVE LIFE!

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11-18-2007, 02:36 PM	#2 (permalink)
Redog Alero Chapter Secretary Join Date: Aug 2006 Location: Newtown, PA Posts: 777	Is there an RPO code sheet on the trunk lid? Probably a 2 series gear. I would guess 2.56 or 2.73 The code should be a GU code, and G80 which is a posi