Initial pressure for R888s

cossie1600

The R888 are unlikely any tires I have driven. With the stiff sidewall, the car can run on 30psi without rolling over. Yet somehow the tire seems to work better with pressure between 38-44psi, the car just has more grip with the high pressure. It is odd to say this, but I recommend 38-42 cold pressure on the R888 (a tire which I hate). I think Toyo recommended the same thing.

Nikon FM

If you hate the tire I'm guessing that is experienced based? If so what's your story on different pressure setups including temperatures and how many laps before noticed affects etc. => Aiming at were the tires up to temp prior to any bad experiences?

Next time out I'll try "a little" more pressure.

Thanks!

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cossie1600

The change in tire pressure wasnt noticeable in terms of feel, but I was averaging .5-1.5 sec faster per lap. It honestly doesn't make the car feel any better, but it is faster in my experience with them (on two different cars).

I just don't like them because of the price to grip factor. For the price close to the A6/R6 or R1, they don't even come close in terms of grip/time. On the other hand, the RA1 were slow, but they could last 3x as long. It's all about grip to life to cost factor for me, I just don't see the reason of getting the R888 unless you absolutely need to drive the car to an event and in bad weather. There is a reason why Toyo is re-releasing the RA1......

I was a long time lover of the RA1 on my 350z, then I sold the car and got a C6, I used R888 on it for 2 years, then I moved to a RX-8 where I tried R888/R1/Dunlop street tires.

Sharif@Forged

Most people get the feeling that the side is actually a bit softer than some DOT race tires. I get that feeling when driving them. The lighter the car, the stiffer they will feel.

38-44psi is on the high side, but if your setup allows you turn faster lap times, then do it. The stopwatch doesn't lie. If I ran mine that high, I would be slipping all over the place.

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cossie1600

Compare to A6/R6/R1, of course it is softer. I was comparing it to the RA1 sorry.

As I said before, the car felt no different on low or high tire pressure, yet the times just came down with the higher pressure. I guess that's the reason why Toyo recommends it. I honestly didn't believe it at first as the tires look fine on the lower tire pressure, yet the lap timer didnt lie and gave me the consistent result (lower times on higher pressure).

Bluemeanie

Actually there was an article on the corvette forum regarding the 888's which I used on my '07 Z. They found that a higher pressure ( 38 and higher ) made the tires work better. They did on my Z, about 39 if I remember correctly. On a very hot day 100+ my times were going down when everyone else's were going up FWIW.

Stan