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paulredlegs
07-07-2010, 05:57 PM
I am currently running bridgestone RE 92 tyres

36 Front

34 Back

would running 38 front 36 back be better?

2002 TJ Exective 3.5L

or any other suggestions?

Sondar
08-07-2010, 11:29 AM
I would think tyre size & profile are more relevant to tyre pressures than the make & version of the tyre.

In any case, both options sound a bit high to me. Standard pressures for my 2002 GTV (225/50's) are 29 front, 26 rear, subject to an increase under max load conditions.

Running pressures that high might give you better fuel consumption, but you'll get a harder ride & probably increased tyre wear.

Frankie
08-07-2010, 12:11 PM
I would think tyre size & profile are more relevant to tyre pressures than the make & version of the tyre.

In any case, both options sound a bit high to me. Standard pressures for my 2002 GTV (225/50's) are 29 front, 26 rear, subject to an increase under max load conditions.

Running pressures that high might give you better fuel consumption, but you'll get a harder ride & probably increased tyre wear.

I also have the same car but with 235/45/17's. I run 39 on the front and and 32 on the rear.
Any less than that on the front and you can see the bulge at ground level.
Previously the fronts were at 32 which resulted in the tyre tread wearing on the sides more than the centre, hence the increase in pressure.
All tyres are different so let the way the tread wears be your guide.

VRX257
08-07-2010, 12:32 PM
I am running stock 17' magna rims. I pump in 40 front and 35 rear. It helps with the fuel consumption, but not all good on traction.

lith
08-07-2010, 12:53 PM
34/32 sounds good.

i think tyre pressures are completely up to you and what you define as 'better'. in terms of prolonging your tyre life, if they are wearing faster on the sides pump them up a bit more, if they are wearing faster in the centre deflate them a bit.

the tyre placard says something pretty low...yep 29 and 26 as Sondar posted, which is nice and comfortable and will probably result in the sides of your tyres wearing out early.

for what it's worth i run 36 front and rear. no particular reason other than the tyre wear seems fairly even and i personally value steering response more than ride comfort!

dickie77
08-07-2010, 02:16 PM
I have tried different pressures and have found that inflating the rear about 4 psi higher than front gives the best handlng and road holding for my setup. Whiteline front strut brace, Whiteline rear swaybar (on mildest setting), King SP with Boge dampers al lround, 15 inch 205/65. I am happy with the car. What I have noticed with this setup is that tyre pressures make a big difference, before (when car was standard), changing pressures did not do much. Definitely my car has better road holding with more air in the back tyres. Road holding is most affected by changing pressures, whereas handling is good within a wide variation of pressures. I ahve found I can get reeally good handling, but with some pressure setups, the road holding is not so good (too sensitive to steering wheel changes).

Life
08-07-2010, 02:18 PM
So whats the deal with lower rear pressure? I've always run 40/40 and get good life out of tyres (around 50-60,000km), as well as firm handling and even wear (Well, till I slammed it more and effed the camber!).

Wouldnt the lower rear pressure cause even worse lift? Wheelspin is bad enough!

zero
08-07-2010, 02:34 PM
Weight difference, front to rear!

Sondar
08-07-2010, 03:03 PM
Just to pick up on some of the comments, I've found that running the standard pressure is fine. Wear is completely even accross the tyres & I've done 55,000 on this set with about 3mm left at the front, 4mm at the back (these are Bridgestone Adrenaline 235/45/17's). Most tyres show some side bulge at standard pressure, unless you're into really low profile stuff.

So I guess the answer is to use what feels good to you, taking into account comfort, grip, tyre wear etc, etc...

paulredlegs
08-07-2010, 04:06 PM
I am doing a 3hour trip monday so might go the

38front 36back

peaandham
08-07-2010, 06:37 PM
i have stock 16inch alloys i run 36 front and 36 rear.

altera
08-07-2010, 06:52 PM
36 front 34 rear nuff said..

Dazmag
10-07-2010, 07:56 PM
It depends what you are after, good tyre wear or ride comfort.
I got 110,000kms out of a set of RE92's on my 02 TJ Exec running 38 psi all around.
I have always found that RE92's like a higher pressure to wear evenly.

Oggy
10-07-2010, 08:04 PM
This has been covered (maybe comprehensively?) within the past 12 months, but my 2c is that my 215/60/16 factory size tyres on factory rims need 40psi before I'm happy with the handling.
The ride is harsh, but handling is MUCH better. My only mod is a front strut brace which also helped noticeably.

Once I've got 17 or 18" rims on, I hope to be able to run closer to 36psi.

GTVLAD79
06-08-2010, 02:40 PM
I run 36 front and 34 rear, guy at the tyre shop recommended it. Prior they were always factory which IIRC is 29 front 26 rear?
Huge improvement.

nemrac33
06-08-2010, 05:48 PM
I have 32psi on both front and rear on my 17x7's. TE Magna sedan with 3.0L. Its not lowered.

Stinky_Pinky
06-08-2010, 06:47 PM
Depends on the tyre. Hit up the manufacturer to be sure. My nexens are 36 and I run this all around with good results.

GRDPuck
06-08-2010, 08:40 PM
When my son & I went on the Murcotts Defensive Driving Course they said the lower tyre pressures advised by Car & Tyre manufacturers were designed to give a more comfortable soft ride.
For Handling and Safety (& increased tyre life & fuel efficiency), they recommended around 36-40psi (252-280KPa).
36psi if traveling mainly on suburban roads & occasional freeway driving.
40psi if traveling mainly on freeways & highway speeds in the Country.

Ishrub
07-08-2010, 11:59 AM
There are so many variables it is impossible to say any one set of pressures is best and it is so subjective as to what people are seeking and prepared to compromise on.

I run 42psi nitrogen F & R in my 235/35/18 Goodyear Eagle F1s on the heavy AWD (even more with me and the crap I always seem to be carrying). With Koni Yellow shortened body sport shocks, Lovells springs, uprated Whiteline 18mm rear and 24mm front sway bays and a Whiteline tower strut brace. I also use Whiteline 12mm camber adjust bolts and had quality F&R alignment. Ride is great on highway and only occassionally a bit harsh on urban bumps etc. Grip is suberb and corners and roundabouts are fun wet or dry.