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MG TD TF 1500 - Help needed to complete CWP data table

I have made a small table in Excel that will help anyone considering a change of CWP, to project speeds and RPMs according to the final drive selected.

However to make it really usefull, I feel one should be able to estimate this date with the added variable of non-standard-size tyres in order to provide data for the two columns (with ?) at the right of the table (appended).

Finding original factory data is not easy amd I am seeking data to fill in the blank boxes. For instance, I want to know the circumfrance of the original Gold Seal tyres that came with the TD from the factory .. the TF .. the MGA ,etc.

Its also upon request, an original .xls file with the formulas.

Gord Clark
Rockburn, Qué.


Gordon A Clark

Gordon the excel sheet that Steve Blomberg made is on its way regarding rear end ratios.
Tom Maine (TD8105)

Gordon,

I do not have an original Dunlop left, hower I do have a tire that replaced the originals, and when these were purchased, my criteria was that the circumference was to be the same as the Dunlops. They were a Firestone bias ply and I think I still have one mounted, but don't ask me why. If you think you could use this dimension for your table, let me know and I'll see if I can get at it, as it is with a few others under cover and under the snow.

George
George Raham [TD4224]

Gord the MGTD, mgtf, and MGA were generally fitted with OEM size 5.90x15 from the factory. The diameter of this size tire was 25.62 inches.
I don't know the slight variances between manufacturers, or with the Gold Seal,if any - but it would be negligible, like the difference in air pressures.
You can calculate circumference if you are using that in your formulas.

Dallas
Dallas Congleton

My original Dunlops on the TD were 5.50 x 15 bias ply. Only when I went to the Michelin steel belted, did the size change to a 5.60 x 15.

George
George Raham [TD4224]

Dallas and George,

As far as I know, all TDs and my TFs were delivered with 550-15 tyre. As far as I know, there was no larger tyre offered on the T-Series except for the dealer-installed 560-15 Dunlop P3s - a racing tyre option for the TF.

I bought one TD from new and one TF from new, and I believe these tyre sizes to be correct, especially since it says so in the respective Owners Manuals.

In any event, I have some good information on tyre dimensions for Don Harmer and Thomas Maine and I will re-issue a revised table, especially since I now realize the attachment to my message, had errors in it.

Gord Clark
Rockburn, Qué.
Gordon A Clark

Gordon,

I far as I know the original tyres for TDs were Dunlop C49 size 5.50 15
I'll send you a mail explaining how to calculate the tyre circumference from the tyre size. I will also attach my .xls file which does just that.

John

J Scragg

Gord,

I saved the Dunlop classic tyre table in html format from the Dunlop web site a few years ago. I just checked and it's not there anymore so I have made it into a jpg and attached it. Here you go.

Dave


Dave Runnings

The rolling radius of any tire will vary with tire pressure, wear and load.
Dave Braun

Sorry Gord - bad info on my part. 550-15 is correct.
I was speaking from recent memory of looking at a Moss British Motoring article, (which is incorrect) and the fact that my car had Dunlop 590-15 Road speed tires on it when I got it.

I should have remembered that I had trouble finding a set of Dunlop 550-15 when I restored it.

Dallas


Dallas Congleton

This thread was discussed between 18/01/2011 and 19/01/2011

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