| Author |
Message |
Mitch Alsup (Mitch_alsup)
Intermediate Member
Username: Mitch_alsup
Post Number: 1003
Registered: 4-2002
| | Posted on Thursday, August 28, 2003 - 9:01 am: | |
"What is the best pressure for Toyo tires?"
For what driving purpose? For track driving, on S03's, I find that TWS wants 1.5 PSI to 2 PSI more than MSR for maximum latteral acceleration. I also find that I like 34 PSI to 35 PSI on the road, and 33 PSI at TWS. So the tire pressure has to depend upon the driving venue.
I worked this (tire pressures) out with a pyrometer along with the suspension settings. And I am getting 16 track days and 5,000 miles on a set of S03's At the end, there was less than 1/64" tread on the outside rear tires when the inside edge went 'slick'.
When using a pyrometer, you want a linear gradient from outside to inside edge. If the center is hot, lower the pressure, if the center is cool, raise the pressure. When the gradient is excessive (>20 dF) and the inside is hotter, less camber is indicated, When the gradient is small or the outside is hotter, then more camber is required. |
Dennis (Bighead)
Junior Member
Username: Bighead
Post Number: 200
Registered: 2-2003
| | Posted on Thursday, August 28, 2003 - 8:13 am: | |
Ken Ross wrote:
>Toyo's are great tires. They come with Porsche Turbos and BMW M series cars.
____________
They are indeed great tires for the price. But neither Porsche nor BMW have ever sold any cars in this country with Toyos mounted as original equipment.
vty,
--Dennis
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neal (95spiderneal)
Junior Member
Username: 95spiderneal
Post Number: 231
Registered: 3-2002
| | Posted on Thursday, August 28, 2003 - 7:51 am: | |
how do you interpret the shoe polish test where you put white marks on edge tire before session?
thanks again |
Rob Schermerhorn (Rexrcr)
Member
Username: Rexrcr
Post Number: 784
Registered: 11-2002
| | Posted on Thursday, August 28, 2003 - 5:03 am: | |
Phil, I agree a pyrometer is best. But for track days, not necessary. For customers at track days I just go off of feedback from the driver and my own experience, which is close enough to have fun.
Though if one is utilizing a pyrometer, take three measurements across the face of the tire. Make certain you're inserting the probe into the tread at a 45 degree angle, don't just touch the surface.
Now, your goal with a radial tire is a temperature gradient of about 40oF, hottest on the inside, coolest on the outside, and about an average of the two in the center, i.e. 200 inside, 190 center, 180 outside. If the inside is disproportionally hot = too much camber (or toe is way off). If the outside is hottest = not enough camber.
Center too hot, say the readings were 200, 195, 170, drop 3psi from that tire and run three laps to see if the center temperature drops into an average of the inner and outer.
Center too cool, add pressure.
Rob |
Phil Hughes (Ferrarifixer)
Junior Member
Username: Ferrarifixer
Post Number: 117
Registered: 7-2003
| | Posted on Thursday, August 28, 2003 - 2:31 am: | |
You need to understand what the tyre is doing to make adjustments to it.
You can use a pyrometer to measure the temps across the tyre, if the outside edges are hotter than the inside, it's probably to low pressure, and vice versa.
But, camber and toe also have influence on this so it's very hard to determine. If you know your camber and toe settings then you can make assumptions, if not you'll need to observe any graining or tread roll to decide what's happening. |
Rob Schermerhorn (Rexrcr)
Member
Username: Rexrcr
Post Number: 783
Registered: 11-2002
| | Posted on Wednesday, August 27, 2003 - 3:39 pm: | |
Neal,
There exist few absolutes when it comes to individual vehicle dynamics. One can make generalizations, and discover trends that generally work for many or most situations encountered on the racetrack.
Your answer is: both adding or reducing tire pressure to increase grip will work, you must try it to find what works best for your car, your tires, your driving style, your track, that day's weather, etc.
My chassis tuning article applys well to Ferrari. Experienced racers may discover a solution different from other's suggestions.
Race tuning is an iterative process, there are no 'magic bullets'.
Have fun,
Rob |
neal (95spiderneal)
Junior Member
Username: 95spiderneal
Post Number: 230
Registered: 3-2002
| | Posted on Wednesday, August 27, 2003 - 2:59 pm: | |
i agree with the post about tire pressures but it is at odds with what tire rack recommends for their racing tips. they state add more pressure to the tire that needs more grip. ie. add to front if understeering and vice versa for oversteer. i am confused please help |
Rob Schermerhorn (Rexrcr)
Member
Username: Rexrcr
Post Number: 780
Registered: 11-2002
| | Posted on Wednesday, August 27, 2003 - 11:23 am: | |
quote:What is the best pressure for Toyo tires?
Chassis Tuning Ferrari's for the Racetrack |
dave handa (Davehanda)
Intermediate Member
Username: Davehanda
Post Number: 1728
Registered: 5-2001
| | Posted on Tuesday, August 26, 2003 - 11:02 pm: | |
Ken,
How long ago was this that BMW was using Toyos? I have been looking at BMW's a bunch the last year, and the 2001-2003 cars I have seen all had Dunlops... |
Ken Ross (Kdross)
Member
Username: Kdross
Post Number: 431
Registered: 2-2002
| | Posted on Tuesday, August 26, 2003 - 8:09 pm: | |
Toyo's are great tires. They come with Porsche Turbos and BMW M series cars. I had them on my BMW and loved them. I would have purchased them for my Ferrari, but I get an awesome deal on Dunlops from the Tire Rack.
Ken |
Joe Craven (Rscapri2600)
New member
Username: Rscapri2600
Post Number: 38
Registered: 7-2002
| | Posted on Tuesday, August 26, 2003 - 8:00 pm: | |
I have a lot of experience with Toyo RA1s which are they R compound DOT legal race tire. They are one of the best values out there, great traction and durable.
They stick the best when tire temps are between 150 deg F and 220 deg F. Hot pressures between 32 and 40 psi work well. I've gone as low as 30 hot in lighter cars w/o problems. |
Philip Airey (Pma1010)
Member
Username: Pma1010
Post Number: 392
Registered: 7-2002
| | Posted on Tuesday, August 26, 2003 - 5:45 pm: | |
Miata guys raved about them particularly when they started sponsoring autocross stuff. All I have heard is rave reviews. Like Dave, I'd start with similar pressures as the OM - and "tune" from there. FWIW, my 77 GTB with 16 inch rims was rated at 32/34 I think. I ran 36/32 at the track (thanks Rob) with street tires. Will go back to 34/34 with comp tires, build the insight from this base.
HTH |
dave handa (Davehanda)
Intermediate Member
Username: Davehanda
Post Number: 1722
Registered: 5-2001
| | Posted on Tuesday, August 26, 2003 - 4:32 pm: | |
Toyos are mainly sold through Les Shwab dealers, which is good, as they have hundreds and hundreds of dealers throughout the westcoast. Free flat repair, free air checks (if you don't want to do it yourself), and free tire rotations (usually not possible on a Ferrar). I have two friends with Toyos on their 512TR's, they may not be the best tire out there, but their are respectable, as one of those guys is at the track with his 512TR freqently and races a BMW. He said he got stuck out in nowhere and needed tires and Les Shwab was the only place for miles...he was impressed with them. Don't know on the air pressures, but I would use the higher of whatever is recommended as the starting point. |
Dave Wapinski (Davewapinski)
Member
Username: Davewapinski
Post Number: 577
Registered: 8-2001
| | Posted on Tuesday, August 26, 2003 - 4:21 pm: | |
For an 89 Mondial t:
The previous owner put Toyo Proxes T1-S tires on it. They are Z rated.
I looked in the owner's manual and they list tire pressures for Mich. and Goodyear tires (different pressures).
What is the best pressure for Toyo tires?
What are the advantages and disadvantages of Toyo tires - I am not famaliar with them?
Thanks, Happy Labor Day Weekend!
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