# what are your tires and pressures?



## kismetcapitan (Nov 25, 2005)

I'm sure something like this has been floating around, but tire pressures seem to vary as much as the color of socks people prefer. So I thought I'd start a thread and people can put their preferences, like so:

tire: Kumho Ecsta SPT, 255/40R17
street/drag/circuit: street
pressures: 2.7 bar front, 2.4 rear

I more or less pulled my tire pressures out of a hat, going higher in front to discourage understeer, and trying to go on the higher end overall for better tire integrity at very high speeds (a friend had a tire blow out at 310kph, and yes, he shit his pants). But I really don't know where I am with my tire pressures (and Kumho hasn't been able to supply me with any baseline numbers to start from)


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## Cris (Sep 17, 2007)

Tyre: No brand, 255/35R18
Street
Pressure: 37PSI all round ~2.55bar

Pulled the pressures out of a hat. I generally like to run a reasonably high tyre pressure though it does vary with the tyre size and construction- some have very stiff sidewalls which are happy with less pressure and vice-versa.

So far my tyre wear seems pretty even.


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## ATCO (Feb 2, 2003)

Road/sport tyre for high speed road/track use - starting point of 40psi front and rear as advised by the 24hour guys.

Drag starting point is 20psi or less depending which tyre you are using.

However, there are so many variables, like surface grip, suspension set up and so on.

DaveG


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## Nocturnal (Nov 5, 2004)

I was running high pressure (38psi I think)

And my tyres was wearing more in the middle then the side, so I was advice to put the pressure down to around 36-34psi to get more contact patch.


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## Miguel - Newera (Sep 18, 2003)

(RX-7) Potenza RE55S S-tyres (Hard sidewalls). Mostly 2.0 & 2.2 bar for road use. On the track, as tyres will heat up considerably more - run 1.7-1.8 bar. 

(AE86) Potenza RE-11 tyres. Mostly 2.2 bar for road use. 
For drifting, 4.0 bar at the rear and 3.0 bar at the front +/- 0.5 bar (depending on ambient temps) 

As you ride Kismet, bikes also run lower pressure on the track, than on the road - for the same reasons as above in the first paragraph.


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## iceager (Dec 23, 2004)

Goodyear F1 Assymetric 265/35/18 run 35-38PSI for Road use.


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## GTRich (Nov 29, 2008)

Have got bridgstones on front [ they were all round ] had avon put on the back on sunday ... front 36 rear 34 .. seams ok


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## StretchGSK (Oct 24, 2006)

For the street surely the Nissan recomendation would be the best?
Or does this only apply to the OEM wheel/tyres?

I run 2.3Bar all round on my R34 (as per the book)
But am in the process of fitting some Falken RT-615's so may re look at that


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## GTRich (Nov 29, 2008)

I would think its a diff preasure for diff rubbers all depends on structure of tyre n how hard or soft the rubber is


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## GT-R Glenn (Nov 9, 2002)

Dunlop R 265 40 17 
28 to 30 psi
Pirelli 255 40 17 P zero 
32 to 34 psi


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## jae (Aug 28, 2002)

tyre: *Falken FK452 265/35/18*
street/drag/circuit: *Street*
pressures: *34psi* front, *32 psi *rear

Noticeable (to me  after six and a half years, with five of them running Falkens) if any tyre more than 1 psi adrift from others. More pronounced if it's a front tyre.

Fuel consumption increases if all tyres over 1 psi out.


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## GTRich (Nov 29, 2008)

Ta ..thats what i was trying to say ... ..


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## ru' (Feb 18, 2007)

T1R 275 18s, 34 front 32 rear cold pressures (psi obviously lol).


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## Bucky (Mar 21, 2003)

Have people noticed that some people run nearly the same boost pressure as tire pressure :chuckle:


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## seagull (Jan 15, 2007)

bridgestone RE55S semi-slick 

front 1.6 bar 
rear 1.7 bar


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## R.I.P.S NZ (May 7, 2004)

MT street 40psi front, 6-8 psi rear


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## ATCO (Feb 2, 2003)

Rob, I thought MT recommend not to go below 20psi?


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## m6beg (Apr 21, 2003)

For your information guys.

This might be why you are having your troubles with tyres Rob.

Proper use of Mickey Thompson ET Street Radial 

Inflation Pressures 


On the racetrack DO NOT use starting pressures below 11 psi. 
Recommend pressures for:

P295 and larger sizes: 11-14 psi 
P275 and smaller sizes: 12-16 psi 

On the highway we recommend running 75% of the max psi as notes on the sidewall of the tire.

Burnouts 

The tread compound used in the ET Street Radials is designed to heat quickly and does not require a heavy burnout. Continue the burnout at a level RPM until the engine starts to pull down. We do not recommend a dry hop after the burnout.

Bead/Wheel Slippage 

Some bead/wheel slippage (1/2” or less) may result during the course of a 1/4mile (or 1/8 mile) drag race. This is normal. Check for tire slippage when you check your tire pressure after each pass.

Excessive Rim Slip

If continued or excessive (more than ½” to 1”per run) wheel/slip is experienced, Mickey Thompson recommends the use of “Beadlock” wheels for ET Street Radials. Bead screws are not recommended and could lead to tire failure and or damage.

That has been taken from MT'S web site.

Mick


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## R.I.P.S NZ (May 7, 2004)

ATCO said:


> Rob, I thought MT recommend not to go below 20psi?


Atco and Mick......I'm using a 31 x 16.5 x 15 not a normal tiny street radial. :chuckle:

For a 2800lb car they reccommend around 8psi, we have tried up to 13psi and down to 6 psi (cold, which would come up after a decent burnout anyway) and it made very little difference.

If you guys saw the state of my transmission you'd know why every other change we tried made no difference, its absolutly worn out and really quite amazing the car ran 165mph at all.
It certainly explains why the car went slower the more we turned the power up.

We'll get the trans sorted, start off gently again and slowly wind it back up.

Rob


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## 95GTR600 (Jun 24, 2008)

Rob
What about tire pressures F/R on R34 GTR with DOT drag radials ?


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## R.I.P.S NZ (May 7, 2004)

I havn't used radials on the Drag-r, only x-plies.

I think Ludders has tried radials but I'm not sure what pressures he ran.

Rob


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## 95GTR600 (Jun 24, 2008)

Rob
And usually on x-plies do you use a lot more air in front than rear or same psi on all four ?


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## TREG (May 20, 2004)

265/35/18 on T1R Toyos.
Road use 32-33psi


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## Dani (Nov 13, 2009)

Potenza RE-01R. all 2.6


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## curtisgoodman (Jul 12, 2008)

BFG G-Force Sports 245/40R17 32psi front 30psi rear


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