Jmccreary

I am wanting to install a 140 mph speedometer in my '80 vette. Does this require a gear change?

e3pres

You will have to change the speedo drive gear in the transmission. It's very easy to do. Just disconnect the speedo cable from the tranny, the loosen the retaining bolt that holds in the 'bullet' that the cable screws on to. Remove the 'bullet' and the plastic gear. Go to your local chevy dealer and tell them that you need a gear for a '78 Vette with your specs. You'll need you trans type, rear gear, and rear tire specs. Be sure to ask for the '78 and not the '79. I tried to get one for a '79, and since some of them came with the 85 mph speedo, they gave me the wrong one.

Good luck. :cheers:

e3pres

BTW - I'd get new O-rings for the gear and bullet while I was at it. It's always a good idea to change them while it's apart. I think there about $0.10/ea.

BSeery

nope nope nope....

You just have to get a speedo that is made for the 1980 that displays up to 140 MPH.

There are several vendors that sell them, Zips for sure, but I know there is one that sells them ultra cheap and I was just about to post asking for the contact info.
I think the guy is called "tic tock doc" or there was another called redline gages or something like that.

Someone will chime in soon. :lurk:

BSeery

Found the info:
http://forums.corvetteforum.com/zerothread?id=485417
http://forums.corvetteforum.com/zerothread?id=472863
http://forums.corvetteforum.com/zerothread?id=305554

Gator81

Yep, you got it. UKPaul put one from Redline Gauge in his '81. E-mail him with questions about it. I plan to do the same one of these days... :rolleyes:

e3pres

That's if you use the special made gauge. If you use a factory gauge from a '78 or early '79, you have to change the gear.

Jmccreary

Thanks for all the advice. I called Redline and ordered the speedometer. What a great price. They are even going to set the milage to the current milage on my old unit... all for $56 dollars.

J
:party:

PROSOUTH

The speedometer is magnaticly calibrated. The only difference is the numerals on the face. Red Line will do you an excellant job. They actually used the factory face the last time I talked to them.

The speedometer gear in the transmission is calibrated to the rear ratio and the if rear ratio is being changed it requires a transmission gear change, but
the speedometer 85 or 140 MPH is not a "Special" gear.
http://www.redlineg.com

CORVETTE CRAIG

JM:
Glad to see you ordered the speedo. I'm happy for you.
I've had mine for over a year, and I love it. Best upgrade/ investment yet.

What a difference a vendor can make. Let's see:
$56.00 for a working functional speedometer from Redline, vs. $90.00, for two hunks of carpet called floor mats, from any of the larger vendors.

:_dupe:

Jmccreary

Update: Got the 140 mph speedometer last night. Simple to install. Works great, except the needle bounces a little once it passes 140. :cheers:

Thanks for all the help on this one.

J