bowmanized

LAKEVILLE, IN (March 17, 2009) -- In an effort to offer our valued customers more tire size options, Hoosier Tire will be introducing four new R100 radial slick sizes for racers competing in GT classes. A new R80 compound will be offered as well in a few sizes when used primarily on the front end of the race car. Extensive testing has proven these radial slicks to perform with the best in class. Every aspect of vehicle dynamics, grip, turn in, steering feedback and quicker lap times, will be enhanced by using these radial slicks. These tires will be in stock the week of March 23rd.



Item
Number Tire Size Width Circ. Measured Section Weight MSRP
43835 265/645R18 10.1" 25.5" 80.0" 9-10" 10.0" 10.9" 25 $380.00
43870 320/650R18 12.0" 25.7" 80.75" 11-12" 12.0" 13.0" 29 $440.00
43875 315/690R18 12.3" 27.3" 85.6" 11-12" 12.0" 13.5" 31 $440.00
43890 310/710R18 12.4" 28.1" 88.4" 10-12" 12.0" 13.6" 32 $440.00

fatbillybob

Boy those are some funky sizes. On a C5 you'd have to run the 265 and the 315 but the 265 is a bit narrow and the 315 is too tall at 690. These must be more of a spec tire for specific cars in gt??????

Also, when hoo hoo made the old grand am slicks they seemed slower than the R5 (iirc) of the day. They needed to build a tire for that series and rules and everyone used that spec tire I think so ultimate speed was not an issue. Maybe they wore like stone because they needed the endurance? Anyway point being this new tire may not be for speed

AU N EGL

The older Grand AM slicks and the VRL slicks were the same rubber compound. Both were harder for endurance races. the VRL side walls were also heavier to take the weight of the Vipers.

I have bought VRL scubbs for a long time. Good long lasting tire. Not as fast as R6s. VRL Only came in two sizes 18x305/30 and 18x335/30

Hard --> soft

GA / VRL -> R6 -> A6

with the GT 80 and GT 100 compound it will be interesting to see how they perform.
Is not the Koni Challenge series of Hoosier GTs as the spec tire?

bowmanized

The taller rear is the new technology in tires and will be for the future. Basically it gives you more rake and more importantly increases your tires 'footprint'. Also has a bigger leverage point so more grip coming off the corner as you apply the throttle.

These were created for the Porsche Cup boys but I"m not sure yet how fast they are compared to others. I know these are nothing like the Grand AM 'wear like iron' slicks. Those are endurance tires and a 'spec' tire. These are meant to compete with the Michelins most of the cup guys use.

AU N EGL

Good to hear

fatbillybob

Very interesting. Can you tell us more about how this works? Does the foot print squish or something because of the extra rubber and that is how it gets bigger? I wonder why one would not change rake by spring collar height on the coilovers? I would think that a taller tire would just add in another source of unpredicatable wheel rate since the tire is sort of a spring. What is the mechanics of the taller tire more sidewall theory? Is there a new dynamic in the lateral x-y plane and the vertical Z axis too?

AU N EGL

larger rear diameter tire is also a slightly larger gear.

trackboss

Diameter increases the tire patch more so than width. As was pointed out though, rear gear may need to be changed to take full advantage. I personally would like to know what sizes (michelin, dunlop,etc.) on C5 cars with stock bodywork and 11" front 12" rear wheels.
Bowmanized, I only see three sizes of the michelins on your site. Are there any 28 or 29 width tires available in those, and what compounds?
thanks,
-V

Sidney004

The larger sizes are 5-6 pounds heavier than the old GrandAm GT60's, must be a very different construction.

J Ritt

If anyone has a current source for Hoosier VRL scrubs (305/30/18), please shoot me a PM. Thanks!

Mallett zo6

I am in the same situation as the rest of you that use the VRL sizes. My car is tubbed in the rear where I used the 335 and the front's (305)'s are huge, but they fit. Anyway, I do not see these sizes availible anymore.

I have yet to see a big 31" tall tire to fit under a C5, except the C5r, but that has wider body work. Anyway, any suggestions...?

Cloaked323

What's the latest it's on this tire.

redtopz

If you can find scrubs, these make a great summer hpde tire IMO. Once they heat up they have excellent grip and don't seem to fade during a session like a R6 or A6. They also seem to last a long time from a treadwear standpoint. I found a leftover set of scrubs for free last summer from a Porsche Cup race at Infineon (R80 front and R100 rear). You can also buy them new from Hoosier, but they cost more than new A6/R6. Just be careful on your first 2 laps.

Cloaked323

Cool thanks for the info