PSI

benoj · Dec 9, 2009

Just checked my tyre pressures after recently buying the car.

Rears were around 20, fronts were around mid 20's

Bumped them up to 33/30 as per the manual.

Car now feels very squirmy and skate like on roundabouts and such, it was like glue before. Do you guys find that less pressure works best?

Luke335 · Dec 9, 2009

I'd say most people prefer slightly under 33/30. I would try around 31/28 and see how that feels. I would have thought low to mid 20's will see you wearing the shoulders of your tyres out pretty quickly.

marrow · Dec 9, 2009

Is your pressure tester/pump working properly?

benoj · Dec 9, 2009

marrow said:
Is your pressure tester/pump working properly?

It was a air pump at a shell garage, so I have no idea.

Cue · Dec 10, 2009

dont' trust it then - those are notorously inaccurate compared to calibrated pressure monitors.

ruffeo · Dec 10, 2009

I usually go 31 front 30 rear

benoj · Dec 10, 2009

Where can I find a calibrated machine?

I know morrisons have an electronic air pump where you input the psi you require and it stops once it hits it, rather than the press a button and the dial shoots of the scale then let go and wait for the line to settle. But this digital one is 15miles away so can never go because the tyres are never cold.

Dan493 · Dec 10, 2009

Halfrauds sell a digital tyre pressure gauge for about £5-£7 ive got one and so has my mate who's got a DC2 and when he had his wheels aligned the bloke said his pressures were spot on so they must be fairly accurate.

nickboazracing · Dec 10, 2009

I think the more important thing would be to check them with the same gauge each time to ensure continuity when you adjust them. Demon Thieves will sell you a good quality gauge.

http://www.demon-tweeks.co.uk/products/ ... lgrp=MS009

Also it's better to check and adjust them when they are hot as the pressure will increase when hot and this is the state they are in when you are driving.

benoj · Dec 10, 2009

nickboazracing said:
I think the more important thing would be to check them with the same gauge each time to ensure continuity when you adjust them. Demon Thieves will sell you a good quality gauge.

http://www.demon-tweeks.co.uk/products/ ... lgrp=MS009

Also it's better to check and adjust them when they are hot as the pressure will increase when hot and this is the state they are in when you are driving.

oh I thought it was best to check them cold. I'm going past a decent tyre gauge at the weekend, what sort of PSI should be looking at after 30mins of driving to be the equivilant of 30/28 cold?

nickboazracing · Dec 11, 2009

I'd imagine on the road at this time of year you'll only see a couple of psi increase. I'd go for a couple above and see how it feels, you can always bleed a bit out of you still feel it's a bit skatey. I think the important thing is to have it right for you, and if you feel happier with them a bit lower then go for it!

benoj · Dec 11, 2009

nickboazracing said:
I'd imagine on the road at this time of year you'll only see a couple of psi increase. I'd go for a couple above and see how it feels, you can always bleed a bit out of you still feel it's a bit skatey. I think the important thing is to have it right for you, and if you feel happier with them a bit lower then go for it!

Think I'll pull up for 10mins or so and let them cool, shouldnt take long like you say - its cold! Then I am going to try 30/28 and see how that goes.