Tyre Pressures On Lowered Car

[Mr.Rudus]

running 32 psi cold all around on lowered car. when I go up to the recommended of 35 psi the ride is very harsh, although I get a bit better mpg and throttle response.

any of you guys with standard suspension find it harsh ride at 35 psi ?

could be my suspension setup is on the stiff side too, so do lowered cars need to run less tyre pressure ? ? any thoughts ?

[Mr.Rudus]

I guess not - - -

[sjrainsford]

One up they should be 33 as standard anyway which is what I run mine on. Although, it isn't lowered. On mine, 35 is if you're loaded or averaging over 160kph.

[gstarr60]

My cars lowered 40 mm, I've tried running on 35 psi as i was advised but the car was lagging alot, and the tires looked quite low, so ive tried 40 psi. Many say that isn't really safe but it works wonders for me. The ride is slightly bumpier but not really that noticable, I guess that also depends on your road surfaces as well. Any less than 40 psi the tires look quite low. I'm assuming as well it has to do with the tire profile as well. I'm running on 215/45/R17.

Hope this helps

[Mr.Rudus]

well gee, I have tried 40/42 psi & what a diff it made. superb drive & for some weird reason the harsh ride is not as worse as 35 psi!

32 psi was sucking my fuel & you are correct on the lag. although it was very comfy like sitting on a leather sofa at home.

the car seems alive & more spirited.

I know the suspension will have to work more, rather use that than put more strain on the engine & gearbox.

[sjrainsford]

At that pressure, your tyres will wear unevenly though. Lowering a car makes no difference to what your tyre pressures should be, the car is still the same weight.

But if you prefer the drive at that pressure then maybe it's worth them wearing faster in the middle of the tread.

[Mr.Rudus]

I done a test with the chalk on the tyre.

the tyre seems to be wearing better correctly all even.

before it was more towards the inner edge, even with 35 psi.

I think lowering the car puts more strain on the inner tyres.

but hey the overall drive etc is spot on with the ridiculous high pressures!

[sjrainsford]

With you saying that, I may just give it a try for the heck of it. Bet it would give a fuel consumption improvement for me going up and down A roads all the time!

The chalk test doesn't tell you the full story though, as you can still have all of the tread touching the road, but one area may have more contact weight, so the only time you find out is 10k miles later when it has worn much quicker. Or with regular depth checks across the surface.

[Mr.Rudus]

that's true, the chalk test wont be full accurate. guess will have to wait about 10k then - -

less throttle required with these high pressures so I am assuming less fuel.

but as I say, cars lowered might benefit from this pressure. not sure though - testing testing - -

[Stuart Aspey]

Hi guys. I'm running stock suspension and standard 17" Lexus wheels. I run 38psi at all times. The rideis good and not too harsh, but I've done this for fuel economy testing reasons. Lol. Use it as my daily driver (only car) and my wife thinks the ride is great. As a step up for the previous car (first gen Vauxhall Corsa)

Lowering the car should not alter the pressure as the cars' weight is likely to remain the same.

[Mr.Rudus]

thanks Stuart , how your tyre wear been ?

so I am not the only running higher pressure along with gee.

all good then -

[Stuart Aspey]

I had my alignment done with WIM as well, tyre wear is even, but I was down to 5 mm after 10,000 miles. I think some people have said if you want durability, you loose out on wet weather grip. But I bought my tyres because they were B rated for fuel efficiency and B rated for wet weather grip.

[Mr.Rudus]

I get the alignment done every set of new tyre change.

I have noticed in the wet you cant corner as hard as it will break traction and slide but helps pump the water through the grip and avoid getting sucked in the puddles! (aquaplaning) but other than that its all good.

with higher pressure the car behaves totally different and gives a some what easier drive.

I guess in the end it comes to the driver and the style of driving, as for me I do many motorway miles and the higher end of pressures suits me just well'