1985 Vette gear set

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Jan 15, 2013 | 07:13 AM

patvette

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1985 Vette gear set

Hi:

I haven't been here for a while.

Last year I read something about getting a bigger pop off the line, and someone suggested a gear set change to a 3.07. Sounded good at the time but I forget most of the details.

Will this change affect my top end?

I checked on ebay for "Chevrolet gear set 3.07" and found nothing. Can anyone give me a better string of words for me to Google so I can learn more?

Thanks all.

Jan 15, 2013 | 07:32 AM

WVZR-1

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Quote:

Originally Posted by patvette

First of all you need to determine what you actually have. Do you know? Is it an A4 or manual trans of some sort, a D36 rear or a D44 presently?

Jan 15, 2013 | 07:33 AM

patvette

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Quote:

Originally Posted by WVZR-1

First of all you need to determine what you actually have. Do you know? Is it an A4 or manual trans of some sort, a D36 rear or a D44 presently?

Ah crap. It's in storage for the winter.

Jan 15, 2013 | 07:37 AM

WVZR-1

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Quote:

Originally Posted by patvette

Ah crap. It's in storage for the winter.

You can't remember if you had to put it in PARK when it went to storage?

Jan 15, 2013 | 07:40 AM

patvette

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Quote:

Originally Posted by WVZR-1

You can't remember if you had to put it in PARK when it went to storage?

Oopsie. So early in the morning.

Automatic

Jan 15, 2013 | 07:44 AM

WVZR-1

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Quote:

Originally Posted by patvette

Oopsie. So early in the morning.

Automatic

I believe the move to a 3.07 would be silly if it's original now with no problems. The rear is likely a 2.73 presently and a 3.07 would be a gain yes but I'd think minimal for the expense. If you've got issues with the rear presently then maybe if you were looking to replace it then a 3.07 could be a wise move. It would NOT appreciably effect top speed. SOP will be minimal. I think there's a 3.07 D36 in the for sale now.

Jan 15, 2013 | 07:57 AM

patvette

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Quote:

Originally Posted by WVZR-1

Thanks WVZR-1. I thought it would dramatically increase my off the line take off. Nothing wrong with the rear end now.

Probably just the winter blues here in the bitter north..

Jan 16, 2013 | 02:22 AM

gerardvg

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From: Melbourne, Victoria, Australia

My 85 has a T700R4 with D36 rear that has the 3.07 performance option gears. At 100kmh (62/63 MPH) rpm is 1,900. Standing quarter from stock standard 16 or so years ago when i got her was 14.4 top speed was 150 something mph, with headers adjustable fuel pressure regulator and cold air intake got that down to 13.3 sec quarters before i put a blower on.

She never ever bogged down, just wheel spin the first gear on the T700R4 is great for launching from stand still or pulling trees from the ground (if you use a c4 as a tractor).

the gearing is that good.

Great mileage is an added bonus.

My 85 has been supercharged for 6 years and the D36 has been fine, the same cannot be said for the half shafts i have twisted a couple of the aluminum ones before i got some steel ones made.

I am sure a manual would kill a D36 and have seen several who have also killed the D44 rears with manual transmissions even with little h/p increase. The D44 was used on all manual c4's from the factory, the auto trans is more gentle on the differential.