Jump to content

Recommended Posts

I'm obviously going to be out on my own with this one but I use 30psi all round and get a good wear pattern. If I'm honest I went up to 30psi thinking steering would be a bit lighter. I don't drive it that hard so cannot say if its really changed handling as such. 

Neil

Link to post
Share on other sites

With modern thin sidewall tyres the lower pressures aren't good. The sidewalls flex too much reducing grip, especially in the wet.

I use 32 all round. Excellent tyre wear, lighter steering and good handling wet and dry.

 

Link to post
Share on other sites
  • 5 months later...

My first TR, a 2, ran on 32 all round on Pirelli Cinturatos 165 x 15.

My current TR, a 3, runs on 32 all round on Bridgestone All Weather 175 x 15.

David

Link to post
Share on other sites
8 hours ago, 2long said:

Would the skinnier 155 tyres on my TR2 warrant the same pressure as a 165?   I use 30 psi.

Dan

I use 165 tyres on one TR2 and 175 on the other, both with 32 psi all round. These modern tyres have very thin sidewalls and low pressures allow them to flex too much. This will affect wear, grip and ride. Cross ply tyres, and early radials, had thick sidewalls and deformed less at lower pressures.

Importantly, as I discovered with the 175 tyres which I set at 24-26 psi to see if it would provide a better ride, I lost control on corners in the wet. Really lost control, the grip was almost non existent on corners above 60 km/h. I reset the tyres to 32 psi and the handling is great wet or dry.

When I buy new tyres they invariably inflate them to 36 psi, that is what modern tyres are designed for. Our wire wheels and suspensions do struggle at those pressures, but don't go too low as the tyres aren't meant to be at low pressures.

Link to post
Share on other sites

I have been running my TR3 with 165 tyres at 24 front and 26 rear, after reading this post I have changed pressure to 30 all round.

Well what an improvement the whole thing feels much more stable, I will now try some higher pressures on my TR6 as well.

Thanks everybody and another score for the forum.

George 

Link to post
Share on other sites

 

2 hours ago, harlequin said:

...Well what an improvement the whole thing feels much more stable...

I've been running 24/26 since being back on the road, but something just doesn't seem the way it was the previous time I drove the TR (40 years ago!)

Never occoured to me to try different pressures.

I'll give 30/30 a try and see what happens.

Charlie.

Link to post
Share on other sites

Read a piece online by a tyre supplier, cannot remember which one, about how to calculate pressures if you have non standard tyres fitted, basically on the tyre sidewall it states Max load at a certain pressure. By dividing the max load by the max pressure you arrive at Kg per pound of pressure. You then need to know the weight of your vehicle, I used the published figures for My TR3 which I think was 960kg and rounded it up to 1000kg, there are 4 tyres so 250kg per tyre, which gave me a result for the 185/70s I have fitted of 27psi.  I use that front and rear and it seems fine, the tyres look right and are wearing evenly. With a full load in the boot and a passenger I would increase the rears to probably 30.

Ralph

Link to post
Share on other sites
22 minutes ago, Drewmotty said:

If you have a front ARB but no rear it’s worth having the front pressures higher than the rear to counteract the induced understeer. 30/28 is a good starting point. 

+1

I do not have an ARB on my 3A and it has a lot of understeer. After almost stuffing it into a field on the B4030 on the way home from Malvern a couple of years ago, and following suggestions here, I recently reversed the tyre pressures so that they are higher at the front. It made a real difference. Car is much more manageable in the corners now.

As to the actual pressures, that is a matter of personal comfort and will also differ with different types / size of tyres. As Andrew says, start with 30/28 and just experiment until you are satisfied.

Miles

Link to post
Share on other sites
1 hour ago, Drewmotty said:

If you have a front ARB but no rear it’s worth having the front pressures higher than the rear to counteract the induced understeer. 30/28 is a good starting point. 

+1

that’s  what I use. 

Link to post
Share on other sites
  • 2 weeks later...

Just got back from a 110 mile drive today from a round trip from Hereford to Builth Wells using a mixtre of back roads and A roads.. Before I left I changed from 24/26 to 30/30.

Yes, there was a positive difference. The car seemed to steer a straighter course without correction. Before it "Bounced about" a bit on rough roads.

I'll be sticking with 30/30 for the time being.

Car is a 3A with standard suspension on T-Trac 2  165/80 15 tyres.

 

Charlie.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

Please familiarise yourself with our Terms and Conditions. By using this site, you agree to the following: Terms of Use.