pgreder

I have a 200 mph face plate but my speedo is the old 85mph in an 87 gt. Does anyone know what to do to calibrate the 85mph speedo to read correctly on a 200mph face?

jeep45238

What the hell do you need a 200mph speedo for?

Musthang

I have the same problem. I was told you should follow the speedometer cable from the dash to the driver’s side of the transmission around there you will find a small plastic colored gear and it is a matter of replacing that gear with the appropriate gear. So the question remains how to find out which gear and where to get it. Maybe you could call a manufacture of a 200mph speedometer and ask if just a gear replacement would solve the problem. I need the same information so pass it on if you find out. Oh, Jeep45238 the answer is because it looks cool. Not to mention what good does an 85MPH speedometer do if you are going 115MPH but maybe you car doesn’t do that.

Milky

Look in the forums, someone wrote out all the different gears and colors you need. I think vfast wrote it but I'm not sure. just replace the gear and becareful with the needles...

TheGmKiller331

Look around on the net there are places you can send the speedo off to and have it recalibrated.

Its a little more involved than a new gear in the tranny.

Quik

its more then just hte gauge overlay. the gearing of the cluster is what you need. most stangs got 140 clusters. you dont need a 200mph unless you plan on running at the saltflats

VertStangGT86

Just get a new speedo, they sell them already calibrated for like 140 or so and you can use all the other stock parts. That's much easier then buying and overlay and trying to figure everything else out

pgreder

Well, first blame the dude who I bought the car from, he liked to pretend 85 on the hwy is 200. All I'm after is a quick way of fixing it. I found out that to calibrate the face plate I have is to use a 30 tooth Speedo gear, 23 tooth is the biggest I believe or seen available. and even then the mileage and trip of the Speedo would be off. So a 89 140mph Speedo is the only real answer for accurate, adjustable, speed and mileage. thanks for all the replies, well most of them.



87' GT T-top.... muscle w/style