hey guys, just decided to get this post going, cos i came across some info today which was quite interesting. I have 17x8" CSA Prowlers with 235/45 tyres on them. and i was kinda unsure on wat PSI to run them on. What do you guys run them on? pref u guys with 17x8's with 235/45's

anyway i rang up the following places, and this is what i got...

Bob Jane T-Mart - 38 Psi (Minimum)

TyrePower - no more than 32 Psi

Beaurepairs - 32 - 35 Psi

So what is what? do tyre people really know what theyre talking about?
on my magna it says that stock they should be 29 at front and 26 at rear. so i usually just add 3 to both. but now im really confused!!

also, one of the guys mentioned that you could usually work it out yourself, by observing where on your tyre you are wearing out. If you are wearing ut the middle of your tyre its inflated too much (too high Psi) and if its wearing on the edges, then your Psi is too low. Some good info i reckon!!

ah well have fun with this

Trav

on my car door (for the vr-x) it says 30 at front and 28 rear. (for 3 passengers) and 32 and 30 for greater than 3.

The higher the pressure the rougher the ride and easier it is to lose traction/slide

On top of the tyres wearing out on the center more on a higher PSI, the steering will be lighter too.

The lower the PSI, you get a harder steering response.

I set mine between 28-32Psi depending on load, driving conditions, distance and weather.. :)

If you drive hard then go a few psi higher than the factory settings. They're designed for people who whinge about things like harshness and don't mind soggy steering and response.

Unfortunately I don't know how a few psi over stock translates to tyres of your size. 38 minimum sounds like BS.
See if there are any HSVs that run that tyre size and see what settings they recommend.

low profile tyres require higher pressure than stock tyres. i used to keep it around 35-36 psi on my civic than has 205/40/17 tyres, 38 psi seemed a bit too high, especially when you hit pothole or bump. i'd keep it around 35-36 psi.

the tyre will have a max inflation pressure on the sidewall. just look at that andthink what ur going to be doing and adjust acordingly. at the moment i have 40psi in the kumo 185/75r14's i got on the front which hjave a max of 44psi and i have 34psi in the back GT radials 215/65r14s which have a max of 36.

but u can go way over the max on the tyre, i read somewhere (i think it was here) of some1 running around 50psi.

but look at the max and the way the tyre is wearing.

Tim

You can go over the max psi listed on the tyre, but forget about long life and reliability. Does a high speed blowout sound appealing? :roll:

~32 - 35psi sounds about right. Tried looking on the tyre manufacturers website?

I run 32psi front and rear in my Corolla (165/75R13). Tried 40psi but it was too hard, nice for handling and speed but **** did it bang the suspension around!

If you're doing city driving use low 30's, for extended highway driving pump them up a bit to mid 30's.

BTW these are COLD pressures, if you do your tyres when warm or hot subtract ~3 - 5psi.

I run 28 psi front and 26 psi back on my VRX.
But i do change it depending on what sort of driving is being done.

36 front and back here. I got stock steel rims and 205/65's.

You can go over the max psi listed on the tyre, but forget about long life and reliability. Does a high speed blowout sound appealing? :roll:


You're more likely to get a blowout from running too low pressures.

i just went to bob janes and told em to fill em up with nitro 20 bucks later all is sweet.

When i get my rims, nitrogen is def goin in mine 8)

and this does....?

Makes you feel good and lets you be lazy :)

A 20% tyre pressure drop reduces tyre life by 15% and pushes fuel bills up by 3%. Over the last few years the filling of tyres with nitrogen has increased dramatically in popularity in countries such as Germany and Italy where almost every tyre shop and garage is equipped with a source of nitrogen

Nitrogen is dry air and doesn't contain moisture. Moisture inside a tire can cause inconsistant expansion and contraction inside the tire resulting in inconsistant tire pressure rises.

nitrogen won't contribute to a breakdown of the inner liner of the tire like compressed air will.

copied that off a few sites hope its handy :)

And how damn lazy do you have to be to lose 20% pressure? I didn't check my pressures for two months or so (because I hadn't done any hard driving) and I hadn't lost any.

Nitrogen will not help you at all in the case of a leak. Checking pressures even once a month completely negates that advantage of nitrogen and avoids low pressures due to small punctures, kerb collisions etc.

[quote:a0db452fe3]Nitrogen is dry air and doesn't contain moisture. Moisture inside a tire can cause inconsistant expansion and contraction inside the tire resulting in inconsistant tire pressure rises."[/quote:a0db452fe3]

Air can be dried too. Who cares about inconsistent pressures when most people have no clue about what pressure they should be running anyway?
How many of you have gotten the pyrometer out to determine whether you are running at the correct pressure?

Nitrogen will help with oxidation of the inside of a tyre. But that's hardly a concern when tyres last me less than a year.

And how damn lazy do you have to be to lose 20% pressure? I didn't check my pressures for two months or so (because I hadn't done any hard driving) and I hadn't lost any.

Nitrogen will not help you at all in the case of a leak. Checking pressures even once a month completely negates that advantage of nitrogen and avoids low pressures due to small punctures, kerb collisions etc.

[quote:ccaad13d6a]Nitrogen is dry air and doesn't contain moisture. Moisture inside a tire can cause inconsistant expansion and contraction inside the tire resulting in inconsistant tire pressure rises."

Air can be dried too. Who cares about inconsistent pressures when most people have no clue about what pressure they should be running anyway?
How many of you have gotten the pyrometer out to determine whether you are running at the correct pressure?

Nitrogen will help with oxidation of the inside of a tyre. But that's hardly a concern when tyres last me less than a year.[/quote:ccaad13d6a]

i check the pressure all the time i have a compressor and air pressure guage here, the nitrogen doesnt loose as much pressure over time as normal air does and most people dont know when to fill there car tyres either. hot ? cold? i read somewhere that 80% of cars on the rd dont have correct tyre pressure.

nitrogen holds pressure over the tyre and they last longer and when you runnin big rims, dash is good yes ^.^

MiG you have to be so lazy as to not check your tyre pressures for 2 months after they have copped a pounding on bad roads. :p

When I pumped mine to 40psi I was too lazy to check them for 2 months, then when I did check them 1 (drivers front) was down to 28psi and the other 3 32psi each. But the roads around here are shit, full of potholes and lumps and ridges... pounds the crap out of your suspension (and I'm sure it's contributed to the early death of my rear wheel bearings and shocks).

I usually do mine at least once every 2 weeks when I fill the tank completely, and they might be down 0.5psi at most (from 32psi).

Mine went from 36 to 33/32 and I reckon they were last checked 2 - 3 months ago. Lazy, I know.