On the subject of 888s ... we had not had the chance to test on them before racing on them this past weekend, so we can't offer any "back to back" testing data like Mitch's .. only more seat of the pants feedback, so here it is ...
Mason liked them on a wet track - very predictable.
In the dry, at first I hated them - they felt like street tires compared to shaved RA1s - probably because they ARE street tires with their big angled tread blocks - I drive a lot of cars on a lot of different tires and it took some time for me to adjust and learn to use these things effectively. By the end of the weekend, I hate them less ... pretty good for street tires
It does seem like they need higher starting pressures than RA1s .. a few PSI, although we need to do some real testing before we can say this for sure. Likewise as to the question of whether they are slower than RA1s - gut feeling says yes - perhaps 1/2 a second a lap around MSRC in an AI car.
They are clearly a "stiffer" tire, which would account for many of the CMC/CMC2 guys finding they need to soften spring rates some to make them work - we probably don't need to alter our spring rates for AI, but we did need to make shock adjustments to compensate.
Despite being stiffer, they got up to working pressure faster than RA1s - I'm guessing this is due to the tread blocks walking around and creating more heat. They also clearly fall away significantly when they get too hot.
So we have a tire that gets hot quickly, works fairly well for a couple laps, then starts to fall away, but we can't run lower pressures to make them stay on the pace longer because although they are stiffer, lower pressures build heat faster due to sidewall movement and that compounds the heat buildup from the tread movement .. in other words, a street tire!
Having said all that, they remain drivable when hot, just slower - at least for a hard driven 20 minute race - who knows how they will hold up in a 40 minute race? Oh and it does look like they need to be heat cycled - the first dry session we drove on these stickered tires where we got any heat in them on Saturday, they really went away fast once they got up to temp - they were fine on Sunday.
I found that these tires do not like to be over driven .. start exceeding the slip angle, and they suck - they obviously get too hot - this is not what I would consider a desirable trait for CMC racing - you guys who are used to hanging it all out lap after lap on RA1s are gonna have to tidy it up, or you will be slower and chew through these 888s like they are going out of fashion.
Once we are all using them, comparing them to RA1s is a mute point - at least for the rest of this season - we have to learn to adapt and live with them. My feeling is that these "street tires" will add a dynamic that an AI team like Cooke/Melkowits with our discipline and testing oportunites can learn to adapt to and live with, but overall for NASA style club racing in general, this is a HUGE step in the wrong direction, and given that we think they are going to last half as long and they cost significantly more, doubling our tire bills in the current economic climate is not going to be acceptable or achievable to many drivers/teams.
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Originally Posted by Al Fernandez
For those that haven't wondered into that territory yet, it's going to be fun watching the expressions when see the time sheets and are 1-2sec slower 8) 8) 
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