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Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - Original TD tyres

What is the correct original tyre size for the TD? I've googled this question & it seems there are two opinions on this; 5.50 x 15 & 5.90 x 15. Surely they can't both be correct? Cheers
Peter TD 5801
P Hehir

5.50x15 was original - I have a rolling chassis with Dunlop's, that has 25,000 miles!

Tom Lange
MGT Repair
t lange

Dunlop "Fort" tires in a larger/wider size of 5.90 or 6.00 (I would have to double check)were also available as an option - the MG parts listing for the TD even mentions an adapter/spacer plate for use on the dual spare tire carrier for these larger "Fort" tires.
DLD

My fading memory tells me that there was no such tire size as a 5.90 x 15 when the TDs were manufactured.
Jim Merz

They were 5.50 X 15 cross ply which are illegal in Australia and I think unprocurable. IMHO crossply tyres track whereas radial don't.
John...Sydney
John Walton

DLD that would certainly explain the two sizes given on the net. There's plenty there also on the radial v cross ply question & so I don't want to reopen that debate here. I do like the look of the TC with its tall skinny rubber & wondered if a taller tyre could be fitted to the TD? I don't want to change the wheels, just the rubber. There is still an original Dunlop on my spare & it seems quite tall & skinny. I certainly wouldn't risk driving on it though, not because it's a cross ply but because of its age. Cheers
Peter TD 5801
P Hehir

Sorry to butt in but is there a consensus "good" source for original looking and original size tires for the TD?

Tim
TD12524
TW Burchfield

Tim, try Coker Tire at www.cokertire.com

BobbyG
Bobby Galvez

John, I'm not to sure about your comment on cross plies being illegal in Australia, in fact there are quite a few TD's and TF's in South Oz. with them on. Maybe we haven't caught up with the rest of OZ yet!!
Don TF 4887 "Figaro' (on radials)
Don Walker

Don, That's what the local tyre supplier has told me anyway there is no way I would put a cross ply tyre on my car. I had them on my MGA at one time many years ago and couldn't wait to change them.
John...Sydney
John Walton

John, I wouldn't have cross plies on my TF either but I did have cross plies on my TC for many years, in fact in the 1960's I had a 1952 Porsche 1500 S with 5.00 x 16 " cross plies, and yes, I had to see if it did 100mph, and it did. I'm surprised I'm still here too.
Don TF 4887 'Figaro'
Don Walker

It seems the taller tyre has a higher aspect ratio. The original ratio was 90, the current radials are 80. As the radial equivalent of the 5.50 x 15 (155-15) is almost non existent, the chances of finding a high aspect 15" radial are somewhere between Buckley's & none. I've yet to check the AR but Brockley make a high performing road/race vintage looking 15" tyre. It not only looks good but does extremely well in all classes of vintage, veteran & classic competition in the UK. If you can believe the blurb they're apparently beating all commers! And they have terrific durability. As I said above, I'm not interested in debating the relative merits of either the cross ply or the radial however, you can't ignore the Brockley. Sure they're not cheap & apparently more than a little noisy, BUT, wouldn't you know it, it might surprise you to learn that it's a cross ply! Cheers
Peter TD 5801
P Hehir

Peter, Have you heard of Longstone Classic Tyres in the UK? Their website is longstonetyres dot co dot uk. They specialise is tyres for our sort of cars and have some interesting stuff on their website. They also have some helpful, (and amusing), YouTube clips.
Michael
M R Calvert

Yeah Michael. I checked out their site a while back. Seems like the higher aspect tyre is NLA. Cheers
Peter TD 5801
P Hehir

Typo in the above. It should read Blockley. Cheers
Peter TD 5801
P Hehir

I did double check in the Factory TD Parts listing. A 6.00 x 15 sized tire is listed as a "Competition" option. This tire was fitted to a different steel wheel - one with a slightly wider measurement I would imagine. The special wheel is also listed in the Factory Parts listing. I imagine this wider wheel was rarely ordered - I wonder if anyone has identified their car as having them?
DLD

Thanks Bobby.

Tim
TW Burchfield

I wrote a "Tech Tips" article for our club's January newsletter to alert members about the dangers of driving on old tires. However, I also discussed tire sizes of bias-ply and radial tires. Maybe it will help you.

The original MG documents that I read listed only 5.50-15 tires for TDs and TFs. Other MG documents may list more sizes.

MGA's had 5.60-15 tires. 5.90-15 were available on some models.

"Experts" suggested that replacement tires (radial or bias-ply) should be within 3% of the outside diameter of the tires that the manufacturer originally installed on the car.

The outside diameter, section width, and aspect ratio of original bias-ply tires varied slightly by manufacturer for the same size tire. Modern reproduction bias-ply tires also vary by manufacturer.

To eliminate variances between manufacturers and to show the relative difference in outside diameters for various tires sizes, I calculated the O.D. in inches using the formula in the article.

> Click on the link below. Read on-line or download by clicking on the "download icon" in the upper middle of the screen to download the file. (A downward pointing arrow with a bar across the tip.)

Link:
http://drive.google.com/file/d/0BxisXBEpc-IWS3RJdUtFLWVySkE/view?usp=sharing

Disclaimer - I'm not a tire expert. Some of the information may be wrong.

Lonnie
TF7211
LM Cook

Tim Burchfield - to me your question is like fixing a car - it can be good, fast or cheap, but no two can apply at a time.

The original tire was bias ply Dunlop 5.50x15 and you probably will not run that now, with good radials available. The Michelin X is the only period-correct tire still easily available, but at a price.

I recommend using whatever decent radial tire can be found at a discount price - Discount Tire, for instance, where sometimes they do and other times they don't have anything in the 165x15 size. They are all made overseas, but are so many light-years better than what was available in the 50's that it really does not matter today. They will handle great, last years, and be under $200 each - sometimes WAY under. Hankook, Nanking, Vredestein, whatever.

If you show your car, get a set of Michelin X tires, and then get a set of Discount Tires to drive on.

My $.02.

Tom Lange
MGT Repair
t lange

I am still running a set of Dunlop 5.50 x 15 bias ply on my TD. The sidewalls are crazed so they have probably seen their last showing unless it goes to a special show.

I have a set of Royalton 5.60 x 15 that will go in their place.

Note you can also use a 5.60 x 15 which is much easier to obtain than 5.50.

I just don't like the look of the radials on TD/TF but that's just me.

The picture of a new set of Dunlops is from Sandy Sanders. He claims they still had factory air in the tires. :-)


Christopher Couper

When we restored a TD and an MGA in the late 70s, you could buy the proper sized Dunlop bias-ply tires for about $25 each - those were the days!
DLD

Peter,

The original tyres on TDs and TFs were Dunlop 5.50x15.

They certainly are not illegal in Western Australia and I suspect they are perfectly legal in every Australian state.

The supply of 5.50x15 Dunlops has virtually disapperared.
I purchased 5.90x15 Dunlops from Vintage Tyre Supplies in UK
about 18 months ago. Nice. They indicated to me they were not supplying anymore 5.50s at that stage. VTS could supply,I think from memory, an Excelsior tyre in 5.50 x15.

As such,for Concours events,5.90x15 are acceptable.

A new set of cross ply tyres on a TD/TF give a more than satisfactory
driving experience. Many of the problems re tyres are often a result
of the front end units not being extensively rebuilt!!

Cheers.
Rob Grantham
TF3719("Aramis"),TF9177("Athos").

R GRANTHAM

Thanks Rob. I guess my hope of fitting tall (aspect ratio 90+), skinny (5.50) tyres to my TD can't be realised in a radial. As the TD/TF front end was set up for the on road footprint of the cross ply & not for the larger contact area of the radial, the more than satisfactory driving experience that you mention, is not at all surprising. Cheers
Peter TD 5801
P Hehir

I'm using Blockley 165VR15 tyres on my TF. I'm happy with the appearance and performance. The bigger tyre footprint must be better for grip, yet I don't experience any negative issues concerning steering weight, as its still very easy. However I have never driven the car with crossply tyres. Not only do radials have a lower aspect radius than the original tyres but owing to flex in the tyre wall, rolling radius is further reduced. This is not a disadvantage with a 5-speed gearbox and higher gearing, but might be with the std box, unless a higher rear axle ratio is fitted.
Dave H
Dave Hill

Any chance of a pic or two Dave? Cheers
Peter TD 5801
P Hehir

Peter,

The roads in Australia today are much improved from the 1950s.
Cross ply Dunlops are fine!

I agree with Chris,the radials just don't look right on a TD/TF.

Bit like the Karvel original carpet versus the modern replacement carpet. The Karvel may not be as tough,however it looks bl..dy good.(lol)

Cheers and keep smiling.
Rob Grantham
tf3719("Aramis"),TF9177("Aramis").
R GRANTHAM

These wheels and tires were on my car when I got it. Their Dunlops. Sold the set of wheels and the tires went with them. They looked like new, but being so old, I wouldn't trust them. PJ

Paul161

These are Blockleys - they don't like crossply tyres, but I like them anyway.
Dave H


Dave Hill

My preference always was for cross plys Rob. If I could afford them I'd be using the Blockley 15" as I think the pattern has a vintage look that suits the car. I'm with you & Chris on this. Cheers
Peter TD 5801
P Hehir

Lonnie,
It's a good article,,, hope people realize how dangerous it is to ride on old "good looking" tires!,, one thing that could be added, is to also find out what the max PSI rating is,, a set that i ordered (and sent back) from a repro manufacturer was only 34PSI,, kind of low for some reason???

Steve
Steve Wincze

it's simple,just ride on new,good looking Cross Ply tyres !

Cheers
Rob Grantham
R GRANTHAM

This thread was discussed between 30/01/2016 and 02/02/2016

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