Toyo 888 pressures?

[carribine]

I'm doing a track day at Oulton park on the 20th and was wondering what pressure should i have in my tyres? There 205/50/15 888's.

[furbster]

I normally drop mine to 30psi all round when cold.

Works well for me.

I do check them everytime I come in as they will go up about 3-4 psi when hot - just let them back down to 30.

Remember to take a pump with you to pump them back up for the drive home!!

[Fushion_Julz]

R888s work best at 40-45psi hot...

What you start at cold will depend on the weight of your car and how hard you drive and work the tyres...along, of course with air and track temperatures..

The nearside front will get hottest...at least on a right handed circuit...

Running the tyres at too low a pressure effectively means too low a temp. too....that will reduce the grip you get from them...I've also found that too cold they aren't as predictable

[DanThe]

I had mine at 24 cold 28-29 hot the other week at Oulton, I was surprised at how quickly they became shite after having good levels of grip for about 10 laps, front geometry on my car needs setting properly which doesnt help..

Will have to try them at higher pressures next time

[staley_turbo]

Dont let the pressure out when there hot. If they start at 28psi cold, and get to 36 hot, don't let
Them back down to 28 when hot. Run rears slightly lower.

[UweM3]

R888s work best at 40-45psi hot...

What you start at cold will depend on the weight of your car and how hard you drive and work the tyres...along, of course with air and track temperatures..

The nearside front will get hottest...at least on a right handed circuit...

Running the tyres at too low a pressure effectively means too low a temp. too....that will reduce the grip you get from them...I've also found that too cold they aren't as predictable

At least somebody who shares my opinion. I found them best at around 40-42psi.
running them too low just overheats them and they go off too quickly. Not to mention the increased wear rate.
I am not too impressed with R888's anyway and since they became pricey they are off my tyre list completley

[furbster]

Interesting!!

I'll try that next time!!

[oldbimmer]

R888s work best at 40-45psi hot...

What you start at cold will depend on the weight of your car and how hard you drive and work the tyres...along, of course with air and track temperatures..

The nearside front will get hottest...at least on a right handed circuit...

Running the tyres at too low a pressure effectively means too low a temp. too....that will reduce the grip you get from them...I've also found that too cold they aren't as predictable

At least somebody who shares my opinion. I found them best at around 40-42psi.
running them too low just overheats them and they go off too quickly. Not to mention the increased wear rate.
I am not too impressed with R888's anyway and since they became pricey they are off my tyre list completley

I'd have to agree there - I run mine at 32psi cold, which brings them up to about 38-40psi hot. Things just don't seem to feel right at anything lower.

[Black_Potato]

You're all

For a track or race day

23-24 PSI cold to get to 30-32 PSI hot.

[freddiet123]

R888S

Running 320 in PBMW race series to the weight limit 1125 kg R888S work best after 3 laps and do not like to be overheated,we do not have hard suspension compared to some set ups and are getting good life out the tyres,off side front getting the hard work ,we set the pressures to max at 30 psi when running hot ,and adjust to air and track temp as it changes we have lap times with in 1.5 sec per lap off quickest with a novice driver still learning tracks

Interesting to see the pressures that are being run on road / track cars

[staley_turbo]

You're all

For a track or race day

23-24 PSI cold to get to 30-32 PSI hot.

Nooo! e30`s are too havey for that. 27-29 cold, 35-37 hot.

[Black_Potato]

Cough.. 950kg

Maybe thats the variable here.

[Mikey_Boy]

In my (limited) experiences with R888's on my road / track car (but note, 205/40 17s..) I have found them to be best about 34 - 36 psi hot.

Weight is clearly a big variable here as are driving styles, how many heat cycles the tyre has seen and also how the tyre is warmed up.

Tending to agree with UweM3 as well since the price has shot up.. How are folks finding alternatives?? Interested to hear what tyres Uwe uses?

Have thought about getting latest Contis or Michi pilot sports as an alternative that can stand the wet a little better?

[UweM3]

Dunlop DZ02 ! 1500km on Nuerburgring, no road use. still at 60% and EVENLY worn, no washed out grooves or chewed up edges.
But I do swap wheels around quite frequent.

[Mikey_Boy]

Thanks Uwe!

Great point about even wear as well - mine are down near the wear bars in places, but near 4 mm elsewhere... Bit odd...

[kimbo]

Bear in mind that you're adjusting pressures to get the tyre to work at the optimum temperature - this will depend on a number of factors, such as weight, ambient temperature, driving style, etc, etc.
There was a similar thread a while ago on which I posted the setup instructions from Toyo's comps department. Cant be bothered to look it up, so will reproduce it below.
the following is copied from an email sent to me by Alan Meaker, motorsport manager for Toyo.

The R888 has a semi race construction (very stiff) and a race tread compound. The optimum tread temperature range is between 85C and 95C measured using a probe type pyrometer, and ideally a maximum difference across the tread of 9C. The maximum hot pressure we recommend is 40psi. Camber angles up to 5 degrees are permissible but the final setting will depend on tread temperatures. It is advisable to have as much positive castor as practical as castor induces a beneficial camber change during cornering. I recommend that the tyres be put through 2 heat cycles before hard use.

The pressures you use will initially depend on the weight of the car, too little pressure on a heavy car can lead to over deflection of the tyre and subsequent failure.

Below are some basic settings:

VEHICLE WEIGHT COLD PRESSURE HOT PRESSURE
Very Light < 800kg 17 - 22 psi 22 - 29 psi
Light 800kg - 1000kg 20 - 26 psi 24 - 32 psi
Heavy 1000kg - 1400kg 23 - 27 psi 28 - 40 psi
Very Heavy > 1400kg 27 - 35 psi 37 - 40 psi


As a tyre gets hotter the pressure increases, this is due to the moisture in the air. The cold pressure you set to achieve a desired hot pressure will depend on the conditions on the day i.e. ambient and track temperature, wet or dry. If the day/track is cold you will need to start with a higher cold pressure as the tyre will not get as hot therefore the pressure increase will not be so great.
Hot pressures must be balanced side to side. Once the tyres have cooled you will find that you will have a difference in pressure side to side, if you have been racing on a right hand track you will find the offside pressures will usually be higher than the nearside.

Changing hot inflation pressures by small amounts can be used to fine tune handling.

Reduce Oversteer - Reduce rear pressures or increase front pressures
Increase Oversteer - Increase rear pressures or reduce front pressures
Reduce Understeer - Reduce front pressures or increase rear pressures
Increase Understeer - Increase front pressures or reduce rear pressures

Achieving the required tread temperatures will depend again on the conditions on the day i.e. ambient and track temperature, wet or dry.

You often here competitors saying ”aMy tyres started to go of towards the end of the race”a, this is usually due to the tread getting to hot.

The tread temperatures are constantly changing through out a race, hotter when cornering and cooler when on the straights and cooling even more when you are slowing to come into the pits. Therefore the temps you record in the pits will be lower than those during the race. So if you record temperatures within the range given above the probability is the temps will be too high during the race.

Increasing your tyre pressures will cause your tread temperatures to increase, more pressure stiffens the tyre’s casing which results in the tread having to do more work resulting in the tread getting hotter. Lowering your pressures will cause them to decrease.

Inevitably changing one thing will affect other things, the whole set up of your car is a compromise between anything that is adjustable.

So that all makes perfect sense then!!
Basically test, test, test.
Have fun

Kim
p.s. the tables have got a bit squiffed up in the pasting, but it looks just about legible!

[furbster]

Cant say fairer than that!!!

Top Man Kim - Thanks for that!

[UweM3]

Thanks Uwe!

Great point about even wear as well - mine are down near the wear bars in places, but near 4 mm elsewhere... Bit odd...

that may well be down to wrong tyre pressure.

[Mikey_Boy]

Yep - could be... Talking to a couple of mates who run Scoobys on R888's, the consensus there is they run best about 40 psi so will up mine for my next outting..

Test test test!