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MG TD TF 1500 - Re-calibration methods for speedo

Greetings;

I was not able to find my answer in the archives. It has to do with recalibrating my TF speedo after installing the 4.3 rear end.
I have read reference to some who bought some sort of Stewart Warner gizmo that fits between the speedo and the cable. My question is this: can anyone who has actually done this supply me with a source or a part number for such an item? And, if you have done it, did it work out satisfactorially?
I looked at the Stewart Warner website, but could not see anything like this.

If this option is not really availabe, I am aware of the services of MOMA or Nosinger. My speedo was rebuild only a few years ago, so hate to pay for another "rebuild".

Thanks much

Tom
'54 TF
Tom Norby

I posted this link a few weeks ago... sounds like they can do a geared box to allow for the change? Mine are also in perfect condition and don't need rebuilding, but Nosinger seemed to want to do the whole thing....

http://www.speedograph-richfield.com/html/minature_gearbox.html

gblawson(gordon- TD27667)

Big truck parts suppliers make up adapter boxes that will correct ratios as you need, and I would guess any speedo shop could do it too. They go anyplace in the cable run.

FRM.
FR Millmore

Hello Tom. The problem with the suggestions above is that those sources do not make the boxes with the correct threads to attach to the gear box output nor the correct thread to attach the cable to. Contact me off list, I make them.
Butch
VMG
R Taras

From the truck people, the cables can be cut in the middle, and the box with appropriate fittings installed in the cut, or, you could use end pieces from old cables. But it is good to know that Butch can make them with the right fittings to attach direct.

FRM
FR Millmore

Tom,
The excellent booklet by Carl Cederstrand provides information on the Stewart Warner adapters. The booklet is entitled "Ring and Pinion interchanges for the mg td/TF"; It is sold by Moss as part number 212-350.

Ben
M Prince

Ben
Have you yourself used on of the S.W. adapters? I'm trying to get some first hand information on alternatives to rebuilding my speedo.
I have emailed R. Taras, who posted up above. Anyone out there buy one of his adapters?

Tom
'54 TF
Tom Norby

Had one on my big truck, and had the sense to ask them if they could do it with Smith's equipment. Don't recall if it was SW or somebody else. They said they'd just fit it in the existing cable, or possibly make a cable using the Smith's ends. They have a whole box of little gears and empty cases and fit them in whatever combination it takes to get the ratio you want. I think it cost about $75 but that was a long time ago.

FRM
FR Millmore

OK, I'm getting somewhere. I have communicated with Butch, about his gear reduction box. I also have heard back from someone at Thos.Richfield in England, after looking over Gordon's link, above.
I just talked to someone at APT Instruments in Minn, on Dave Braun's recommendation. That brought up a question.
I see from Cederstrands book that the TD speedos were no longer chronometric when they changed from flat face to dished face.
What about the TF speedo. Is it chronometric or not? If it is not, what would be the wording or title for it's mechanism? Non-chronometric?
Any of you TF guys know?

Happy New Year
Tom
'54 TF
Tom Norby

The TF speedo should be magnetic. As in a magnetic spinning cup drags the mechanism along to a certain value against a spring which wants to return the speedometer to zero. There is no physical connection between the magnetic cup and the pointer. The faster the cup spins, the higher the needle is dragged.

warmly,
dave
Dave Braun

I believe that I got a gear box from APT instruments for my TD. It fit on the transmission (with some trouble from the floorboards). They could not get exactly the gear ratio I needed and the speedo reads a bit high. Enough to scare the passenger to death. 80 MPH in a TD would scare anybody.

Other than that they were nice people to do business with, and delivered when they said they would. Don't remember what the cost was, (a few years ago).
Cheers,
Bob
Bob Jeffers

No need to go to the UK for a speedo re-calibration.

Nisonger in NY do it too, as they are authorized Smith agents.

I would imagine it will be a lot less expensive and less frustrating to have it done, rather than trying to do it one's self.

Frankly, I never changed mine when I went to the 4.3. The rev-counter does an equivalent job. Its just a matter of eye-balling equivalent speeds.

Gord Clark
Rockburn, Qué.
Gordon A Clark

I found my correspondence with Nisonger a pita... when I mentioned that my speedo was in perfect shape and only needed re-calibration they came back with an email that I read as "too bad, its all or nothing, don't waste our time"..... just one of those 'I don't need this......' experiences!!!

It also scared me as both the tach and speedo match perfectly (they should, they are stock) and if they redid it, i'm sure something wouldn't look right.....I'd rather pay $160.00 for a 'box' then send mine away!
gblawson(gordon- TD27667)

Gordon C.
I am very familiar with what Nosinger does. I was not going to send my speedo to Richfied. I was referring to the other Gordon's post of their website. If you link to it you will see that they sell a nice variety of conversion gearboxes to correct the speedo reading.
I am keen on doing this because my TF has a service record going back to the 60's with verification of the mileage over the years. I'd like to keep it accurate as time goes on.

Tom
'54 TF
Tom Norby

On the trip to Gatlinburg, I was on a number of highways with mile signs and tenths marked off.... with not much else to do, I timed and checked the mileage against my odometer and speedometer a dozen or so times....I was exactly 10% low.... so every mile I turned 9/10ths.... I would think it fairly easy to have a gearbox made to allow for that difference?

I know most boxes attach down at the transmission end...is there a problem with just having it attach to the rear of the speedo?
gblawson(gordon- TD27667)

I asked that question of R. "Butch" Taras who made the 4th psoting. His device is placed at the gearbox end because, he says, it puts less stress on the speedo cable. If I buy one of his, I will probably try it behind the speedo first, because I have a lazy streak.

Tom
Tom Norby

This thread was discussed between 29/12/2010 and 01/01/2011

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