[riggsjr]

I have a 1965 GTO and need to get to my speedometer. Can someone post a step by step process to get to my cluster so I can remove my speedometer to have it re calibrated ?

[Tom Vaught]

Usually you leave the speedometer alone and put the right gear combination in your transmission tailstock and driven gear adaptor.

Tom V.

[Dick Boneske]

As Tom said, calibration is done at the transmission end of the speedo cable, not the speedo itself.

[riggsjr]

Let me start over. I did a post a while ago how my speedo is off 10 mph.-10 actually. When I am doing 35 by my speedo my GPS is saying that I am doing 45.I was thinking about putting a pair of pliers on the stem of the speedo and maybe just turning it on the needle.This why I need to know how to remove the dash.....

[Tom Vaught]

Sorry but you would screw up your very nice Speedo-head unit, and that would be really sad.

All Speedometer heads are calibrated to the same curve. (ALL GM speedos turn 1001 rpm @ 60 mph, or 1001 revs per mile).

If you messed with the needle position you would be right at a single point on the speedo gage and still off every where else.

What rear axle gear do you have in your car?

What tire size do you have on your car?

What Transmission do you have in your car?

What changed from when the car was stock out of the plant?

If you can answer these questions, then we can help.

Tom V.

[riggsjr]

Tom,
I was going by this thread responses that I posted a while back.

http://forums.maxperformanceinc.com/...d.php?t=757216

[Tom Vaught]

Thanks for the additional info on the other thread. BIG HELP.

Like was mentioned before the Pointer SHOULD come to a rest at 0 MPH.

I ASSUMED that you were trying to fix a Gear Swap - MPH off issue. MY BAD

It looks like the speedo might have been either a misbuild when the unit was made or you are not the first guy to play with it.

In this case you unfortunately will have to remove the dash to inspect the speedometer head to see if the stop is broke or if the needle was installed on the stem in the wrong position. DO NOT BEND THE NEEDLE.

You should be able to remove the pointer from the stem and "reclock" it to the zero stop position. Stuff happens when they build things. Might have been like that for ~50 years.

Tom V.

[riggsjr]

No problem...
Any help out there to remove dash would be helpful.

[Tom Vaught]

Chrisp, Bill Ryder, and a few others for sure could help in that area.

PM them if they do not reply.

Tom V.

[chrisp]

Disconnect battery , remove front seat , if you have a dash-pad that must come off , i like to remove the steering column , dash controller [heat] all cable ends must be disconnected if removing the entire plastic bezel recommended , remove all bezel screws pull towards you then start unplugging wires most can be unplugged from under dash 1st. Once out you can then remove the cluster from the bezel . Sounds like a lot of time but not .

[riggsjr]

Boy it sounds like a lot of work! Good winter project. Thanks.

[Dick Boneske]

I've taken the cluster out of my '64's many times.

I pull off the speedo cable first. Then remove the five screws under bottom the cluster bezel and five more screws inside the top ledge of the bezel. The bezel is now loose. You can pull it toward you enough to remove the wiring as needed. If you're separating it completely from the car, you'll have to remove the heater control assy. or disconnect the control cables. I don't remember which is easiest, but either is not hard.

One more thing---I still don't understand why you want to remove the speedometer. My '64 reads 65 mph when I'm going 75 on the gps. It is due to the speedo gears being wrong in the transmission.

Does yours read "0" when standing still? If so, there is most likely a problem with the drive gears, not the speedometer head.

[Dick Boneske]

Forgot the pictures.

[GT182]

There's a chart somewhere that will tell you what speedo gear for the transmission you need to go with the rear gear ratio. The right gear will or should fix you problem.

[Dick Boneske]

Here's the chart from the '64 Tempest Chassis Manual.

[John V.]

In an older post, riggsjr showed that his speedo (from a '65 Rally Gauge set-up IIRC) was NOT reading zero when off. Needle was pointing about 10 mph below the 0 mark.

So not a speedo gear issue apparently.

He wants to reset the needle on the shaft. I have no idea if that is a good solution but that is why he is looking to access the speedo head.

[Dick Boneske]

Sorry, he didn't say that in the OP.