70 Differential Marking
Thread Starter
Instructor
Joined: Jul 2012
Posts: 174
Likes: 6
From: McDonough Georgia
70 Differential Marking
I have the following markings on the differential of my 70 corvette:
1CAV1 28 70 W
Can someone please tell me what these numbers and letters translate to? I'd like to know what my differential gear ratio.
Thanks,
Al
1CAV1 28 70 W
Can someone please tell me what these numbers and letters translate to? I'd like to know what my differential gear ratio.
Thanks,
Al
Racer
Joined: Jan 2014
Posts: 407
Likes: 14
From: Mulberry Florida
Larry
Thread Starter
Instructor
Joined: Jul 2012
Posts: 174
Likes: 6
From: McDonough Georgia
Does anyone know if a 3.08 will deliver the best gas mileage?
Thanks,
Al
Race Director
Joined: Oct 2007
Posts: 15,825
Likes: 90
From: Fairfield, VA
Does anyone know if a 3.08 will deliver the best gas mileage?
I had 4:11's on a '69 Camaro and it was terrible driving, but fun at stop lights.
Like everything, it's a trade-off.
You want gas mileage? Get a Prius.
I would leave the 3:08's and create better gas mileage by more efficient driving.
and to edit and add to the problems:
Just because CAV is on the casing, doesn't mean someone hasn't swapped gears inside.
There' a rough test - lift the rear of the car. Put tape on the drive shaft in a precise position - rotate a rear wheel exactly one turn, count how many rotations the driveshaft has gone. Never done it, willing for folks to chime in.
Of course, you could open up the case and count teeth.
Last edited by mchar; Jul 6, 2014 at 05:37 PM.
Thread Starter
Instructor
Joined: Jul 2012
Posts: 174
Likes: 6
From: McDonough Georgia
Well, 2.73 would give you better, but low end performance would suffer a bit.
I had 4:11's on a '69 Camaro and it was terrible driving, but fun at stop lights.
Like everything, it's a trade-off.
You want gas mileage? Get a Prius.
I would leave the 3:08's and create better gas mileage by more efficient driving.
and to edit and add to the problems:
Just because CAV is on the casing, doesn't mean someone hasn't swapped gears inside.
There' a rough test - lift the rear of the car. Put tape on the drive shaft in a precise position - rotate a rear wheel exactly one turn, count how many rotations the driveshaft has gone. Never done it, willing for folks to chime in.
Of course, you could open up the case and count teeth.
I had 4:11's on a '69 Camaro and it was terrible driving, but fun at stop lights.
Like everything, it's a trade-off.
You want gas mileage? Get a Prius.
I would leave the 3:08's and create better gas mileage by more efficient driving.
and to edit and add to the problems:
Just because CAV is on the casing, doesn't mean someone hasn't swapped gears inside.
There' a rough test - lift the rear of the car. Put tape on the drive shaft in a precise position - rotate a rear wheel exactly one turn, count how many rotations the driveshaft has gone. Never done it, willing for folks to chime in.
Of course, you could open up the case and count teeth.
I appreciate your advice and like you said I guess it's all a trade-off.
Thanks, Al
Pro
Joined: Oct 2010
Posts: 695
Likes: 55
From: Palm Desert California
My book shows :
CAV =3.08 rear end
12870 =JAN28th 1970 (Assemble date of the diff)
W= Warren Plant
Don't know what the 1 means before CAV, maybe chevy .
Don't confuse the assembly date with the build date of the car. Assembly date will preceed the build date.
I can only assume that a 3.08 gear will get you a few more mpg than a 3.70.
CAV =3.08 rear end
12870 =JAN28th 1970 (Assemble date of the diff)
W= Warren Plant
Don't know what the 1 means before CAV, maybe chevy .
Don't confuse the assembly date with the build date of the car. Assembly date will preceed the build date.
I can only assume that a 3.08 gear will get you a few more mpg than a 3.70.
Thread Starter
Instructor
Joined: Jul 2012
Posts: 174
Likes: 6
From: McDonough Georgia
My book shows :
CAV =3.08 rear end
12870 =JAN28th 1970 (Assemble date of the diff)
W= Warren Plant
Don't know what the 1 means before CAV, maybe chevy .
Don't confuse the assembly date with the build date of the car. Assembly date will preceed the build date.
I can only assume that a 3.08 gear will get you a few more mpg than a 3.70.
CAV =3.08 rear end
12870 =JAN28th 1970 (Assemble date of the diff)
W= Warren Plant
Don't know what the 1 means before CAV, maybe chevy .
Don't confuse the assembly date with the build date of the car. Assembly date will preceed the build date.
I can only assume that a 3.08 gear will get you a few more mpg than a 3.70.
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Thread Starter
Instructor
Joined: Jul 2012
Posts: 174
Likes: 6
From: McDonough Georgia
Thanks,
Al