Ed Newman

I'll second the notion that MPSCs hydroplane very easy. Maybe not as bad as Hoosier slicks, but they are definitely NOT a rain tire of any sort, not even really an intermediate even at full tread depth.

brucegre

Lots and lots of miles on MPSCs, almost all at Mont Tremblant, and lots of miles on the P-zero Corsa as well.

In no particular order:

For whoever asked, the P-zero Corsa System (looks like a Corsa with two circumferential grooves for water evac) is NOT a real R-compound tire, it's a very good compromise between street and track.

MPSCs are, overall, the most consistent fast tire any of us in Rennsport have run. Hoosiers are quicker for a short time then fall off, Corsas are close but not quite there. RA-1s, we're not sure since none of us run them, but there is one instructor who is trying them now and they look promising.

MPSC are a little sensitive to pressure, but are OK over a 2-3 lb range. On the GT3 they seem to like 32f and 34r hot. As they get old, they take more time to warm up, this must be admitted. But, they always come in and then stick like crazy. Usually, once the pressures are dialed in you never have to play with them again for the event. It takes one to two sessions to get them right, we always go out and get them pumped up too high, then bleed down. If you have to add air to bring them up, you start the process all over again which is a pain.

In the rain, the tire's performance is very much dictated by the track surface. Tremblant is a very smooth surface, and the MPSCs are terrible there in the rain. I mean really terrible. On a track like Mosport or Lime Rock, I would expect them to be good out on the rain line since the asphalt is rougher. However, I run a Dunlop rain tire in the wet, and I will lap the field in a 20 minute session when the other instructors stay on their R's, there really is no comparison between an R or even a street tire and a good race rain. There is, however, a significant difference in drivers in the rain, and for 38D and bobt993, I'd guess that you guys run a great rain line and some of the guys on wets couldn't find the rain line with a map.

Overall, for dry, any temp conditions, I've wandered around but always come back to the Michelins.

ceboyd

....well, I must admit that my MPSCs were pretty well worn when I hydroplaned and not very close to new.. when close to new, they gave me a lot of confidence driving TO the track in a heavy downpour (this much I'll admit wholeheartedly).. and closer to new they are hands down better in the rain any day compared to normal hoosiers (non-rain hoosiers).... (obviously that goes without saying)

38D

I also ran the new R6s in the rain at the Glen race and was shocked at how good they were in the wet (after changing tires 4 times I was just too lazy, so I went out on the Hoosiers). In standing water they are useless, but they are pretty amazing if it not raining enough to puddle. If the R6s are any indication, I can only imagine that the Hoosier rains must be insanely good.

bobt993

Colin, the Hoosier rains should almost be illegal. They are unbelievable in the rain. Tom D (was running the black 993 parked near Larry at the club race) has run them and can only advise to "keep them wet or they will melt". I corded my 05s at our Pocono event in the rain before video session I posted here and they were much better than the MPSCs, allowing me to run hard immediately. Tom was on Toyo R rains and just blew by me in T1 at Pocono during the video. If you look off line, you will see some cars off track during the session. We weren't black flagged since everyone managed to get back on okay.

ceboyd

wow.. you guys with the funds to go with hoosiers, I'm envious!!!

..meanwhile, i face the drive to/from the track to factor into the whole equasion as well

sjanes

What are you guys getting for heat cycles on the MPSC before they go away? I'm close to 40 and they have lost a fair bit of their grip.

bobt993

my tires never last that long or brakes for that matter. I hate to say, I don't know the answer to that one, but I will chalk my new tires next week and get a result. I keep looking for .5sec here or there, so I am getting more and more **** on the DAS, video, tires , brakes,...........I may turn into .........TD! yikes!
just kidding TD, wish I had your convictions, I would be faster already.

Bull

When I ran MPSCs, I found that they were sinificantly deteriorating after 25-30 cycles, and at 35 I didn't want to waste my time on them any longer.

sjanes

OK thanks. That seems to be the same result I'm getting.

ceboyd

the race guys don't seem to like using MPSCs past 6 to 8 heat cycles... seems a waste but if you have funding to do it, why not I guess....

38D

MPSCs are plenty sticky for 15 HCs, and still faster enough to win up to 25 HCs. Anyone that throws then out after 6-8 HCs is just being foolish. (said the D class record holder at Watkins Glen...)

Martin S.

In reality, there is no such thing as an arrive and drive race tire, especially a tire that will be driven in hot weather (The summer). Most tire mfgs will tell you that you need to shave your tires to 4/32. This knocks off the extra rubber that can overheat, and may cause the tire to blister of chunk. Kumho says to shave their tires...the RA-1 works best if shaved. A shaved tire is as good as it is going to ever be, the first time you take it out. I have a set of RA-1s that were shaved...they wear as long as non-shaved tires it seems to me, and they perform better right out of the box.

In a part of the country whare it may rain....you really have four (4) options:
1. Install a roof rack for your tires, or,
2. Get a mini-trailer to hold your tires and tools,
3. Kiss up to a pal and have them haul your tires.

4. The fourth and best option, is to trailer your car to the event. I rented a trailer for an event this past weekend. I loaded up my car, extra race wheels/tires, and I was off. Once at the track, I unloaded and could have been ready to go out on the track shortly thereafter. It is the only way to fly for me...fortunately I have a Toyota Tundra tow vehicle, and I rent a very nice race trailer from a pal for $100 a weekend. I also have peace of mind knowing that if the car breaks, I can get it home.

brucegre

I'm with Colin - I wear my MPSCs out, the last set I had on the car were performing almost as well as when they were new, and I had to change them when I couldn't see the grooves on the left rear. I will get around 20-24 heat cycles before they are worn out. They go off a bit over time, but mostly they need an extra lap to warm up. If you want to see a tire go off, try racing on slicks that are heat cycled out, now there's what a cooked tire really feels like.

ceboyd

i've corded my share of R compounds... on set of the old time BFG R1 I corded so badly that when I pulled up in my driveway, they bubbled out of shape.. it was scary that I drove 120 miles home and made it.. so I try to avoid badly cording tires now... I considered that a very close call and I never want to get that close again!