cstreit

Hey gang,

So the new (to me) cup is finally starting to get in the groove and working better on the track. However we were at Putnam a week ago and I burned through a set of Hoosire R6 rear tires in 4 sessions. (two races, a qual, and practice).

I've resisted moving to slicks because I would have to add weight for my class, but I'm wondering (well no, pretty sure) I'm overheating the tires, particularly the rears. Wondering if the taller slicks might be more effective in the end because obviously two sets of R6's in a weekend are not.

Where (and what price) are you sourcing your Michelin Cup slicks for?
What are my alternatives?

Any suggestions on adding weight to a Cup elegantly (About 75#)

Thanks!

KaiB

Can't help with the slicks, but this is what I did for ballast.

Depending on NASA vs. PCA, I need either 30 or 60lbs . The block pictured is the first 30#, when needed, its mate goes just in front. 1/8" steel straps go above the blocks, and beneath the tub.

analogmike

Hoosiers are a good alternative slick. I wonder if they make a much taller R6, that might work better and give you more load rating.

cstreit

Analog Mike. They make one, but it doesn't quite fit on the car. It rubs on the fender behind the wheel. I tried it. THe P295/40ZR18 is 27.2" tall.

The real issue with the R6 is the sidewall profile. It has the extra wide-section width sidewalls with "curb protection" overhang near the wheel lip that makes the tire much wider than a comparable slick. If I wanted to buy wheel halves I could probably make it work with a little less offset in the wheel centers. even 1/2" would do it. Look at an R6 some time if you've never noticed. Slicks have a V profile it you look at them straight on. R6's are like an upside V, they get wider as you go towards the wheel lip.

cstreit

My other alternative, of course, is to build a weight box that mounts to the passenger seat location and put in the 75-100# I need and run the Hoosier R100 slick. I really liked those on my last car...

I'm thinking slicks are probably worth the 75# and -8HP reduction I'd need to take...

plus I HATE that Hoosier R6 "Gone in 20 minutes" behavoir.

jrgordonsenior

Who are you running with that you have to add weight for slicks? NASA's GTS5 shouldn't be a problem so?.....

I've never found R6's or any R compound to be effective with the whp and wing downforce exerted by a cup car. Slicks can last much longer if you use them effectively. The Michelins are great tires but expensive. Yokohama has their 2011 Patrons Series cup tires on sale at $1,800. per set through Trackside Performance (dot com). If you go to Hoosier slicks try the R80's up front which balance nicely with their R100 rears.....

Ricky Boo-Boo Johnson

I use the Pirelli slicks. The new World Challenge classification.

I take 2 sets to the track. I scrub one set and let it sit for 1 month. The other set has already been scrubbed and been sitting and I can get through a full weekend (2 practices, 2 qualifications - just a couple laps, 2 quali-races-20 mins each, 2 feature races - 20-30mins each) on the one scrubbed and sitting set with minimal drop off (.3 - .5 sec). And I can still run them at the next event for practices!

I get them from Frisby Tire. $520/rear; $395/front

Bob Schaefer
Frisby Performance Tire
702-433-7390
bschaefer@frisbyracetire.com

I use the Yokohoma Advans also - but have found for the price, the Pirellis are giving me the best combination of lap time and longevity for my $$s.

Ricky

boothkc

I have a lot of time on R6s in my prior Panoz GTS (lap times pretty close to 996 cup). A heavy car with lots of RWHP really used up the R6s. Always "greasy" after 20-30' with a loss of grip. We would get 4-6 heat cycles on them before they would get too hard to be fun. Never got to the wear dots etc. Generally a disapointing tire compared to slicks and we stopped running classes that required DOT tires.

Jumped up to 18" Hoosier slicks (again on the Panoz) and much better. 5-10 heat cylcles with predictable drop off before no fun. Lap times 6-8 secs faster (1:55 vs. 2:01-3s) with the slicks... so likely much better trade off for the ballast penalty.

In the 997 Cup I have tried the Michellin slicks which are amazing. Certainly better when new and loose a bit every 2-3 cycles, but fun all the way up to about 10 cycles. Maybe 2-3 sec lap delta from new to discards. 1 second loss new vs 3-4 cycles.

Pirelli slicks in the 997 Cup can only be described as "dissapointing" and that is being kind. Good for less than 1 heat cycle with peak use at 4-7 laps then greasy. 35' into 50' race thought I had a flat they were so bad. 3.5 second delta on 2 heat cycle tires. Basically only good for one race session and a gentle qual.

No idea on Yokes, but some say "a little less" performance than Michellins which seem to be the "gold standard" and priced like it too... About $2500/set. You can only get them from Jackson Motorsport (Debra) 864-272-3160. This is also the "spec tire" required on all Cups for PCA races if you plan to do any of those.

The set ups are quite different for Michs vs. Pirelli vs. Yokes so jumping around too much might be expensive in itself to re-sort the car.

Hope that helps.

Kevin

Ricky Boo-Boo Johnson

Your description of the Pirellis reminds me of the old Pirellis and not the new, World Challenge P-Zeros. Also - I don't think you heat cycled your Pirellis - trust me - IT MAKES A HUGE DIFFERENCE from what you are describing!

Dan Jacobs

I think the Michelin cup n1 slick is a great tire and worth the money. I've used them for years with
zero issue's and a few wins

cstreit

Jgordon I'm running NASA GTS4 with the car. At 325RWHP (restrictor plate) I have to weight 2925 wet coming off track to reach slicks. Right now I'm averaging about 2850#

I want to try and stay with Hoosier Slicks because of the contingency program they offer. 2 years ago I didn't buy a single tire all year. This year they gutted the program and it's not very good, but better than nothing. Eventually I'll probably switch to Yoko's if we can get them to start working with GTS instead of just the spec classes.

Going to order a set or two of the Hoosier Cup slicks and see how they do at our next event.

So with the R80 fronts will I wear out fronts and rears at a good rate? I seem to be burning up a front tire pretty quick. On some level I miss the 2200# lightweight I ran before. Easy on brakes and tires... ...but not quite as fun as the Cup is starting to be.

Zuluracerx

I'm running the Michelin slicks now as well (switched from the Yoke Patrons) and they grip like glue. Yes, more expensive and availability is touch n go but that's my tire of choice (so far).

boothkc

Ricky,
you are correct we did not heat cycle or cure the new tires. However they were this years tires for Pirelli Cup. We used $6000 (3 sets) of tires to run 2 races. Painful. I had heard they were worse last year. It really isn't practical for us to go through a complex heat cycle and curing process, but maybe will have to look into it.

KB

jrgordonsenior

Yokohama most definitely honors their contingency program in the GTS series. It's more generous than Hoosiers, take a look:
http://www.nasaproracing.com/conting...gency_Info.pdf

I'd forgotten about your restrictor plate experiment. Obviously it's worked out well....

cstreit

I was thinking of Toyo and they're new slick maybe...

The restrict or plate worked. I may play with it some more later this summer when I schedule some Dyno time. Ed Baus is also doing some work there.

I think I'm going to build a weight box and try the slicks... now just have to decide which ones. I like the Hoosiers but....