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Discussion Starter #1
I've got Toyos installed few weeks ago.
Stock sizes 235/35/19 front + 265/35/19.
Fronts are new R888R model.
Rears are R888.

This is my first time with 888's and so far i was doing mountains roads driving.
To get to the triangle i've got the ~36psi hot pressure.
I have to say that with higher pressure i felt more confidence but wear was quite far from the triangles. I'll play with this more to decide.

This Friday i will have auto-x competition and i need advise what tire pressure to use.
Our courses are quite tight and quite short (35-45 seconds). Miata-like...
With regular tires (RS, R1R, PSS, PSC2) usually i was adding ~5psi more pressure than usual and it worked for me.

Cambers on my car are ~1'50" all around (almost 2 degr).
Stock PASM with TPC DSC set to stiff, Tarett F+R sway bars, GT3 LCAs.

Many thanks in advance!
 

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I am interested in your assement of the R888R in front. This is a newer model, which I am debating ordering for Autocross vs the Bridgstone RE71R on 18 inch wheels.
 

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pressure wise - i'm still puzzled what's bets for them.
i've tried 27-28 and also 34.

timewise - they're faster than RS3.
the longer the track the bigger the advantage.

on our 29-30 sec tracks difference on Miata's are 0.1-0.3 sec.
 

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Can you tell any difference between the 888R rear and R888R fronts as far as tire patch stick. Did you purposely choose these different tires to resolve understeer in the front? Has this combination worked the way you wanted? I am asking as I will be upgrading to autocross race tires this fall.
 

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Discussion Starter #5
this is what was available locally.
i don't fee any issues with this.
i haven't drive on wet/rain though.
 

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I've used up two sets of RE71R's on my Cayman S. I run 245's in the front and 275's in the back. A set lasts about a season here in Idaho, with two of us driving the car. We also run a couple of hill climb events during the year as well.

That being said, I am going to try the BFG Rivals next time around. The major reason for changing is that the BFG's seems to do better with higher ambient temps. The RE71R's go away (get greasy) on hot days after several runs, especially with two drivers. Ideal would be to have the RE71's for the spring and run Rivals in the heat of the summer.

The single most effective thing I did to reduce understeer was to install GT3 Lower control arms and get some negative camber in the front. Huge improvement in turn in and the car now oversteers at will with the throttle.
 

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PCA in the northwest says no camber plates or non stock lower control arms. If you do, you are put into a class of unlimited modifications, which is no fun. So, I am in the GT category which allows for a modified suspension, Ohlin coilovers, sway bars, bar ends etc, but no camber plates or LCA's. In front, one side of my car needed machine slots to assist the camber to get to -1.6. Rear is at -2.1. Terett adjustable sway bars.

In retrospect, I should have had Cantrell Motor Sports even the camber front and rear at -1.6, but others have made this setup work with sway bars, shocks/springs and size of front tires, which is my route this fall. I am still running Michelin PSS's but hope to change to RE71R's this fall. Seattle usually does not get that hot, so that is where I will most likely go. Most of the Stock Caymans run Bridgestone RE71R's as well and they are very fast. Many have been in the sport for years, so I am still in the learning mode.

Next year I may take a trip to Boise for a summer autocross. I also am including my son in the sport as he is a freshman attending Boise State. Im looking at a small trailer to haul extra tires, jack and other autocross items behind my car or maybe trailer my car behind the family Audi. Not sure how this will work out as I do not have space to store the trailer.
 
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