1980 speedometer difference
Melting Slicks
Joined: Aug 2005
Posts: 2,560
Likes: 5
From: the land of a never ending frame-off resto-mod. May Visa have mercy on my soul.
In 1980 there were 2 types of cars sold. A standard chassis with the 85mph and a few with the 140mph. The 85mph was used because the maximum obtainable speed of the car in the standard configuration was 82-84mph. Some folks were able to get 86-88mph under extremely ideal conditions but this was rare.
The 140mph edition was a special order which included a document the owner signed saying the maximum speed would not exceed 91.8mph. This vehicle was capable of speeds exceeding 110mph mostly on deserted turnpike and western desert road conditions.
Today speedometers are routinely calibrated well over 160mph due to relaxed EPA and CAFE government regulations. In 1980 GM felt it was politically correct to produce the corvette with an 85mph speedometer just to appease the regulators. Also smog equipment kept the car from going any faster UNLESS you new where the S/P (speedometer/performance) bypass circuit switch was located. A well kept secret among dealers and select enthusiast.
The 140mph edition was a special order which included a document the owner signed saying the maximum speed would not exceed 91.8mph. This vehicle was capable of speeds exceeding 110mph mostly on deserted turnpike and western desert road conditions.
Today speedometers are routinely calibrated well over 160mph due to relaxed EPA and CAFE government regulations. In 1980 GM felt it was politically correct to produce the corvette with an 85mph speedometer just to appease the regulators. Also smog equipment kept the car from going any faster UNLESS you new where the S/P (speedometer/performance) bypass circuit switch was located. A well kept secret among dealers and select enthusiast.
Safety Car
Joined: Nov 2004
Posts: 4,359
Likes: 57
From: Mundelein Illinois
I could be wrong, but I thought all corvettes were built with 85 MPH speedo. When the 55mph got lifted to 65 mph people are now driving 80 and 85 mph and the speedo is burried. I believe if you have a 140 speedo the previos owner changed it for the above reason. Owners got a speedo from a 78 or 79 which were 140. That's why I did it. Back in 80 & 81 all American car that I remember were 85. My brother had a Grand Prix is was 85 mph.
Just my thought, and I am no expert.
Just my thought, and I am no expert.
Safety Car
Joined: Oct 2000
Posts: 3,547
Likes: 12
From: Carbondale Pa.
Originally Posted by indy99
In 1980 there were 2 types of cars sold. A standard chassis with the 85mph and a few with the 140mph. The 85mph was used because the maximum obtainable speed of the car in the standard configuration was 82-84mph. Some folks were able to get 86-88mph under extremely ideal conditions but this was rare.
The 140mph edition was a special order which included a document the owner signed saying the maximum speed would not exceed 91.8mph. This vehicle was capable of speeds exceeding 110mph mostly on deserted turnpike and western desert road conditions.
Today speedometers are routinely calibrated well over 160mph due to relaxed EPA and CAFE government regulations. In 1980 GM felt it was politically correct to produce the corvette with an 85mph speedometer just to appease the regulators. Also smog equipment kept the car from going any faster UNLESS you new where the S/P (speedometer/performance) bypass circuit switch was located. A well kept secret among dealers and select enthusiast.
The 140mph edition was a special order which included a document the owner signed saying the maximum speed would not exceed 91.8mph. This vehicle was capable of speeds exceeding 110mph mostly on deserted turnpike and western desert road conditions.
Today speedometers are routinely calibrated well over 160mph due to relaxed EPA and CAFE government regulations. In 1980 GM felt it was politically correct to produce the corvette with an 85mph speedometer just to appease the regulators. Also smog equipment kept the car from going any faster UNLESS you new where the S/P (speedometer/performance) bypass circuit switch was located. A well kept secret among dealers and select enthusiast.
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
Originally Posted by indy99
In 1980 there were 2 types of cars sold. A standard chassis with the 85mph and a few with the 140mph. The 85mph was used because the maximum obtainable speed of the car in the standard configuration was 82-84mph. Some folks were able to get 86-88mph under extremely ideal conditions but this was rare.
The 140mph edition was a special order which included a document the owner signed saying the maximum speed would not exceed 91.8mph. This vehicle was capable of speeds exceeding 110mph mostly on deserted turnpike and western desert road conditions.
Today speedometers are routinely calibrated well over 160mph due to relaxed EPA and CAFE government regulations. In 1980 GM felt it was politically correct to produce the corvette with an 85mph speedometer just to appease the regulators. Also smog equipment kept the car from going any faster UNLESS you new where the S/P (speedometer/performance) bypass circuit switch was located. A well kept secret among dealers and select enthusiast.
The 140mph edition was a special order which included a document the owner signed saying the maximum speed would not exceed 91.8mph. This vehicle was capable of speeds exceeding 110mph mostly on deserted turnpike and western desert road conditions.
Today speedometers are routinely calibrated well over 160mph due to relaxed EPA and CAFE government regulations. In 1980 GM felt it was politically correct to produce the corvette with an 85mph speedometer just to appease the regulators. Also smog equipment kept the car from going any faster UNLESS you new where the S/P (speedometer/performance) bypass circuit switch was located. A well kept secret among dealers and select enthusiast.
You have got to be joking right?
spedaleden, I agree
All 1980-82 (and late 79s) should have an 85 mph (or 140 k/mh) speedo as per Federal Law
Drifting
Joined: Sep 2006
Posts: 1,986
Likes: 21
From: Columbus MN
Originally Posted by wfo76
All 1980-82 (and late 79s) should have an 85 mph (or 140 k/mh) speedo as per Federal Law
140 mph speedometers in an '80 are after-market. Ecklers and other parts sources offer a "restoration" service to upgrade 85 mph speedometers to 140 or 165.
Instructor
Joined: Jul 2003
Posts: 210
Likes: 0
From: eaton rapids mi
Originally Posted by indy99
In 1980 there were 2 types of cars sold. A standard chassis with the 85mph and a few with the 140mph. The 85mph was used because the maximum obtainable speed of the car in the standard configuration was 82-84mph. Some folks were able to get 86-88mph under extremely ideal conditions but this was rare.
You need to read this article. Their 1980 test corvette topped out at 123mph using the L48. I know mine will exceed 100mph with the same motor.
http://corvette.caranddriver.com/arc...leID=79&page=4
Also according to my corvette black book the 85mph speedo was phased in in '79 leading me to believe that only an 85mph speedo was available in '80. My '80 has a 140 because i changed it.
Melting Slicks
Joined: Aug 2005
Posts: 2,560
Likes: 5
From: the land of a never ending frame-off resto-mod. May Visa have mercy on my soul.
Lordy Lordy folks.......... I should become a comedy writer. Too many serious people here.
The 85mph was used because of the 55mph federal speed limit law. We all know corvettes can exceed well into the 120s and beyond. Hell I had a chevette that could do 96mph back then. OK everybody grab you're bats I think I hear my wife calling and I gotta go, see ya.
The 85mph was used because of the 55mph federal speed limit law. We all know corvettes can exceed well into the 120s and beyond. Hell I had a chevette that could do 96mph back then. OK everybody grab you're bats I think I hear my wife calling and I gotta go, see ya.
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Safety Car
Joined: Nov 2004
Posts: 4,359
Likes: 57
From: Mundelein Illinois
Originally Posted by indy99
Lordy Lordy folks.......... I should become a comedy writer. Too many serious people here.
The 85mph was used because of the 55mph federal speed limit law. We all know corvettes can exceed well into the 120s and beyond. Hell I had a chevette that could do 96mph back then. OK everybody grab you're bats I think I hear my wife calling and I gotta go, see ya.
The 85mph was used because of the 55mph federal speed limit law. We all know corvettes can exceed well into the 120s and beyond. Hell I had a chevette that could do 96mph back then. OK everybody grab you're bats I think I hear my wife calling and I gotta go, see ya.
Drifting
Joined: Mar 2004
Posts: 1,873
Likes: 1
From: Savannah Ga
Originally Posted by Avette4me
No way.My 82 will go way past the 85.Ive had it up to 85 and still had a lot of pedel left.I didn't want to brake the speedo so I backed off.It's very easy to go 85 on the freeway.You better be able to go 85,if you don't you'll get past by everybody,giving you the one finger salute as they go by.
Melting Slicks
Joined: May 2004
Posts: 2,084
Likes: 1
From: Aussie expat in Saudi Arabia
Hehehe, if you're not doing 85 down the main street through town here, then you're gonna get shunted from behind! I'd probably be better off getting an aircraft air speed indicator for highway driving! 
10, 165, 1980, 1980s, 55mph, correct, corvette, mph, politically, spedometers, speedometer, switching
