PCA SDR

Since my 944 spec car was built and I started driving it in mid 2008, the R-888’s were the spec tire. So I have only known the R-888’s. With RA-1’s coming back, I bought a set of shaved RA-1’s to use when the R-888’s are worn out.

I started time trialing this year and ran the Streets of Willow in Jan and Spring Mtn in May besides doing DE’s and a few autocrosses. A couple of weeks ago at the Spring Mtn time trial I had the R-888;s on the car on Sat and only got a little faster than my best time from May. So I did a little experiment. I put on the RA-1’s for Sunday. The first run session in the morning I ran my fastest time ever on that track. It was only a fraction of a second faster, but faster anyway on a cold track.

I changed my rear sway bar softer after that first run session on RA-1’s and during the next couple of run sessions I re-learned how to drive my car.

Bottom line, I dropped another 4 seconds during the day as learned to drive these tires.

I’m a believer in RA-1’s now.

Now I can’t wait to see what Chuck Sharp has been saying about RA-1’s. That they can be driven with consistent traction until you loose too much grip because there is too much cord showing.

Greg Trigeiro

I think the general consesus is that the 888 and RA1 offer pretty similar performance, UNTIL the 888 turns off. It is almost like a light switch, they work well and then suddenly they are DONE. The RA1's are consistent until there is more cord on the contact patch than rubber!

It is almost like a light switch, they work well and then suddenly they are DONE.

Yep.

Ditto

Greg,
I am happy that you have now seen the light!

In addition, if your car was properly set up for the R888, then you will want more camber with the RA-1. The general consensus is around -3.5 degrees in the front and around -2.5 degrees in the rear. Very slight rear toe in. Keep the HOT tire pressure below 40psi. They go away completely above 41 or42 in a spec car. Unlike the R888, overheating them does not end their life (but it is still not good for them).

At BW last year, I had 4 R888's on the Turbo. They still had around 50% tread at the beginning of the weekend, but had been overheated previously (don't ask). I was slower than I had gone in the Spec car. I couldn't figure it out. I even had Steve G. check the suspension and alignment - it was OK. I replaced the rear two with two completely worn out RA-1s (no cord, but no tread at all) and immediately dropped several seconds (3 or so, as I remember). I then bought two RA-1's from the Tire shop (not shaved) and dropped another 2 seconds or so, still with 2 shot RA-1's. That is when I became the believer.

You will be very happy!!

I think RA-1's at their best are still faster than 888's at their best. Close to a second per 60 second lap.
The 888's just won't tolerate the heat that the RA1's will.
We killed a set of rear 888's running them 190-200 degrees.
Fronts were still OK at 150-165 degrees.

I think the difference is less with a 944 than a 911 as tire temps are even on a 944 and much hotter in the rear for a 911.
It just kills me to throw away a tire with 50% tread left on it.
Sliding 888' s is death to them.
I have run consistent 220 degree run sessions on RA1's with no ill effects.

I would run something completely different if RA1's weren't coming back.

Thanks Chuck. Jae Lee had already set things up about what you stated with a little toe out in the front.

Greg Trigeiro

Jad wrote:I think the general consesus is that the 888 and RA1 offer pretty similar performance, UNTIL the 888 turns off. It is almost like a light switch, they work well and then suddenly they are DONE. The RA1's are consistent until there is more cord on the contact patch than rubber!

Yup.

According to Steve at C2 and Bryan at Toyo's Only, the RA-1's are slated for a return in many sizes soon. Apparently, the mod's made for the R888's just didn't work and the complaints from individuals and racing clubs sealed the fate of the R888's. I've never heard any word on shaving the R888's. Does that help?

For some real fun, try a set of Toyo R1-R's (140 Rated) as practice tires. They offer some pretty remarkable grip for a 140 tire. One person told me the compound is the same as RA-1, the tread thickness is much fatter.

One theory about this rating thing: if you use a softer compound and fatten the tread depth, you get slightly longer tread ware (tread life). So, an RA-1 with a depth of 6/32nd and an R1-R with a tread depth of 8/32 or 10/32 can be rated differently since the "tread-life" is longer with more tread depth ... both using the same rubber compound in the tread-block. This is just a theory I've heard from a tire supplier. Could this be true?

First of all... the 888 does not even look like a race tire. The last 3 sets of tires on my car were 888's, and I am so glad to have the RA1's back. They hold that edge just a little longer. I have always felt that the 888 overheated quickly then went away. Glad to have them back!!!

Just bought a pair of rears as I corded them at Spring Mt after about 30 heat cycles.
Chuck @ Race Tires direct still has some in stock sizes vary.. YMMV
Race Tires Direct; Las Vegas 702-433-7390 No affiliation
Good prices and fair shipping.

Steve Coe at C2 Motorsports has RE-1's also. They are a new advertiser in the Witness so please give them a call. They mount tires also. Telephone is 858/4959200. SUPPORT OUR ADVERTISERS