tyre pressures

[Marigold]

Hi, I have read some of the discussion on tyre pressures but none of them seemed to mention my tyres. Anyone any tips on what pressure my 165/80 x 14 's should be? Thanks k

[MarkyB]

I'd experiment around the 30 psi mark.
Are they on wide rims?

[Marigold]

Hi, thanks, not sure about wide rims but they are on proper van wheels apparently

[MarkyB]

Even on van rims 165s may be marginal, if they turn out to be saloon wheels, which are much more common, they are too wide.

"Apparently" doesn't really cut it, do a search on van wheels, or rims, and find out what to look for.

[mike.perry]

155/80/14 are fine on car rims so there should be no problem with 165/80/14 on van rims.

[bmcecosse]

I think 165 should be ok on 4.5J wheels - but i wouldn't go any wider! And my guess is 32/34 psi - depending on the load in the back!

[mike.perry]

With larger tyres I don't think such high pressures are necessary. I would start with standard van pressures of 24/28, see how they handle and increase if required.

[bmcecosse]

It will handle like a jelly, and destroy the sidewalls.......look at modern cars with radial tyres - the pressures are ALL well up in the 34/38 psi range..........

[mike.perry]

Modern tyres are often very low profile, therefore a thin cushion of air between the road and wheel necessitating high pressures. 165/80 is normal aspect ratio for a radial therefore a much larger cushion beween road and wheel. I run my traveller tyres, 175/80/13 at 24/26 and there is no sign of sidewall bulging

[MarkyB]

24/26 psi ! Is that because it's what the manual suggests for cross ply tyres?

[mike.perry]

No, it is because I have 175/80/13 on wide rims, any harder and they would feel solid.
I run my Series MM 155/80/14 at 30 psi.

[bmcecosse]

The OP isn't using wide rims - just 4.5J which are actually a bit narrow for 165 tyres. I still think 30 psi is the ideal - for any of the tyres mentioned so far.......

[dalebrignall]

i would go with 30

[Tapitha]

My MGB handbook shows tyre pressures for cross-ply and radial-ply tyres. 5.60x14 19lb/sq.in Front, 22lb rear.
The radial tyre pressures for 155x14 are 21lb/sq.in front and 24lb rear. That is an increase of only 2lb for radials. The MG is heavier than a Moggie so I would have expected higher pressures. 30 lb/sq.in seems high but that is what I am using on my newly acquired 1969 2-door having read the posts on this forum. I found the tyres were 45lb pressure when I checked them the first day after delivery!!!!!