Topic: Speed O
in Forum: C3 Interior
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Lifetime MemberLemon Grove, CA - USA
Joined: 10/17/2007
Posts: 2041
Vette(s): 1982 C3 Collectors Edition 44000 miles, sat in the sun most of its life, My wife purchased it for me for Father's Day in 2007 from her girlfriend that had it for 19 years. It is on the road again. I'm retired but it is now my daily driver.
I was out for a drive in my Vette. It finally is drivable 
. Surges a little but I want to put some miles on it before I worry about that. Nice to be in SoCal in the winter.
Anyway I noticed that everyone was driving fast event for SoCal so I figure I have a SpeedO problem. Got my GPS out and found that it was not as bad as I had thought they were driving fast but I read about 5 miles per hour fast at 70. Is there any easy way of adjusting this?
I have replaced my dash and pulled the gages enough in the last two months that I'm not against pulling them out again but not unless I can fix the problem without sending the gages in.
. Surges a little but I want to put some miles on it before I worry about that. Nice to be in SoCal in the winter. Anyway I noticed that everyone was driving fast event for SoCal so I figure I have a SpeedO problem. Got my GPS out and found that it was not as bad as I had thought they were driving fast but I read about 5 miles per hour fast at 70. Is there any easy way of adjusting this?
I have replaced my dash and pulled the gages enough in the last two months that I'm not against pulling them out again but not unless I can fix the problem without sending the gages in.
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Lifetime MemberHOWELL, NJ - USA
Joined: 5/18/2004
Posts: 6812
Vette(s): 1979, Targa Blue (72 Color), Pace Car rear spoiler, L88 hood, Dark blue factory interior, 525HP 406, HD 700R4, 370 gears,Steeroids, composite rear spring, TT IIs wrapped in T/A Radials.
You may be able to increase the speedo driven gear by a tooth or 2. That will actually slow down the rotation of the cable by increasing the ratio.
If an 82 is similar to several previous years, it's right inside a the housing on the trans where the speedo cable goes in. Theres a metal tab with a small bolt on the trans case that that holds in in place - loosen the bolt and swing the tab out of the way and it should slide out - the driven gear rides inside it. Takes less then 10 min to switch them. Most time consuming is raising and lowering the car...
Driven gear
Housing
Dr. Joel should be on this one shortly also!!
Hope this helps.
Paul
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Duncanville, TX - USA
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
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Well, yer on the right track there Paul, but....the '82 had a 700 trans. The speedo housing is different, tho it is still in the same place. There is a larger, "Y" shaped bracket that holds the housing in the trans, and the housing itself is a large, round, black plastic deal. The driven gears are also quite a bit larger on the 700. In fact, the gear you posted above is for the larger plastic housing for the 700, but the "bullet" you posted is for the 350 type transmission. 
(I'm all about splittin hairs! 
)
On a side note, the 400 trans also used the larger speedo housing, but it is aluminuminum. The Chevy 350 was the only 350 to use the small, steel "bullet" housing. The Buick/Olds/Pontiac 350s used the larger aluminuminum housing like the 400.
True tho, changing the driven gear by a tooth will make a difference. I can look in the parts book to see what gear(s) an '82 should have originally, but tire size is gonna make a difference, too.
What size tires does your car have on it now, Gilbert?
(I'm all about splittin hairs! )On a side note, the 400 trans also used the larger speedo housing, but it is aluminuminum. The Chevy 350 was the only 350 to use the small, steel "bullet" housing. The Buick/Olds/Pontiac 350s used the larger aluminuminum housing like the 400.
True tho, changing the driven gear by a tooth will make a difference. I can look in the parts book to see what gear(s) an '82 should have originally, but tire size is gonna make a difference, too.
What size tires does your car have on it now, Gilbert?
Joel Adams
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Lifetime MemberHOWELL, NJ - USA
Joined: 5/18/2004
Posts: 6812
Vette(s): 1979, Targa Blue (72 Color), Pace Car rear spoiler, L88 hood, Dark blue factory interior, 525HP 406, HD 700R4, 370 gears,Steeroids, composite rear spring, TT IIs wrapped in T/A Radials.
Horse shoes and hand grenades, buddy, horse shoes and hand grenades!!
LukesVette 2009-10-24 10:40:03
And thar ya go - correct picher updated for the 700R4 too!!
LukesVette Homepage
Veteran of Operation Iraqi Freedom
101st Airborne(AirAssault!)
God Bless America
Support Our Troops
Lifetime MemberLemon Grove, CA - USA
Joined: 10/17/2007
Posts: 2041
Vette(s): 1982 C3 Collectors Edition 44000 miles, sat in the sun most of its life, My wife purchased it for me for Father's Day in 2007 from her girlfriend that had it for 19 years. It is on the road again. I'm retired but it is now my daily driver.
My tires are R255/60 R15
in Forum: C3 Interior
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