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GT LE Tyre Pressures

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Totally agree with Andy. I use the quoted pressures, perhaps a pound or two higher on my LE GT. If too high at the front it felt a but skittish so would never put 28 or 30 on the front.

Gentlemen please be informed that modern tyres are made from different rubber compounds as in the days our MGB's were produced, not to mention that the internal steel body of tyres also have been developped.
Ask a tyre supplier, unless you go to Kwikfit but to a serious shop.
Hereby a link to MG V8:

I tried running higher pressures and the handling suffered as a result. Far too crashy and bouncy.

I run a little bit more front and back than standard, around 23 and 25. Part of the suspension comes from the soft sidewalls imo.

I have read the article on the V8 Register page previously and I have still seen nothing to convince me that tyre technology today requires higher pressures. I fail to see why the rubber compounds will make any difference. The pressure of the tyre will influence the shape of the contact patch - of course the shape could also be influenced by the structure of the tyre and many modern low profile tyres now have very stiff side walls, especially the 'run flat' variety. However my engineering logic leads me to the conclusion that in that case less pressure would probably be required as the tyre is to a certain extent self supporting.

On my daily driver (Audi A6 Quattro) I have found over a number of years that if I run the tyres at the quoted pressures then I run the middle out of the tyre - particularly on the backs. This leads me to suspect that part of the current move to much higher pressures is down to regulatory issues - by running higher pressures you almost certainly reduce the rolling resistance and therefore also reduce emissions and fuel consumption and also probably noise. This helps both the tyre and the car achieve better Euro ratings!

Higher pressures also make a manually steered MGB 'driveable' without needing to pump iron before hand! 😉
I have not experienced low grip with my GT on its 185/14 Uniroyal Rainmaster's but yes the cheap (are there any others?) Barum 165/14s fitted to the roadster do not provide so much grip in the wet on their wire wheels. There do not seem to be any other suitable tyres to fit these narrow rims....

Radial tyres were in their relative infancy when the MGB first appeared in 1962 when the public specifications were written. Pretty much all we had then were the Michelin ZX tyre and some early clones from other makers. The Michelins were extremely soft walled. My 1964 roadster, which I owned in the late 1960's came to me with tubed Pirellis fitted to its wire wheels and they had been run tooo soft before the car became mine such that after an extremely fast thrash down what there then was of the M4 this side of the Severn bridge I came down the motorway off-ramp snaking heavily as the rear left deflated audibly at the reduced speed. The tube had become too hot!
I have always avoided under inflating tyres ever since then! Not just because of the hairy decent to normal speeds so much as the damage that this event did to my underpaid wallet at a time when I was saving for a first house deposit! 🙂 Yes, the car became that deposit. 🙁 Clearly vehicle weight and its front/rear distribution is part of a formula that the tyre makers must use in establishing tyre pressures as well as intended top speeds power available etc. It would be so helpful if a tyre company could provide us all with definitive pressure requirements for our cars on their modern tyre rubber and ply construction, so far I have not found any that do.

Maybe it might be an idea to contact one of the clubs (MGOC - MGCC) or the commercial magazine MG Enthusiast to do an investigation or report on this, I remember they did such a few years back regarding tyres for the MGF/TF at a time the Goodyear tyres we not available anymore for a while.
With about a 30,000 MGB's on the road in the UK the question must have been asked before and/or a lot of people might be interested for the result.

I have sent a query off to Uniroyal but no response yet!

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