JMon

I just got my 2001 cup car.
Took it out to Sebring a couple of weeks ago, and love it.
Now I'm going to Daytona in 2 weeks.
I probably should get an extra set of tires.

Right now I have Michelin 24/64-18 and 27/68-18
I’ve been told my springs are 800 and 1000. (I’m not sure if this is accurate)
I’ve also been told (But I don’t understand the numbers): Front 100/60/160 Rear 160/60/180
There is an adjustment on the shocks.

I came from a Carrera S with R888s. I do like the Michelins, but have nothing to compare them to. I’m going to Daytona in 2 weeks and want a tire that is easy to manage, and one that I can get with some ease. (It seems the Michelins are really hard to find and I’ve been told expensive). Some have mentioned R6 (Will that even work?) R100. Also I’ve had some suggestions of Yokos…

Next problem is tire sizing. I really don’t know the equivalent of say the 24/64-18? And 27/68-18. I’m guessing a 245/35/18 and 275/40/18 (But not a common size)

So basically I need help on 3 fronts:
1) Tire type
2) Tire Size
3) Where to buy

JMon

Somone just suggested Toyo Proxy RS1 in 245/640 R18 and 285/680 R18 Any opinion on this setup?

MariusRacer

For Daytona only Michelin or continental slicks!!!! Everything else blows up all the time. Hoosier probably being the worst of them all. A set of michelins is cheaper than wrecking your car in the banking.

JMon

You don't happen to have any Michelin scrubs you want to sell do you?

As another option, Continental 245/40-18 and 275/35-18 a bit smaller. -1.7%f and -3.9% rear. Is that a workable combo for this car or am I loosing too much rear height? 26.7in to 25.3in

jrgordonsenior

Aren't Continental slicks Hoosiers?

The IMSA cup spec tire is Yokohama. We race them consistantly out West and we don't have the blowouts or delaminations that Hoosier and even Michelin slicks have experienced recently. I know the Michelins have the most grip, but the Yokes are close and less expensive. Stay with the 680 series rears for Daytona....

Veloce Raptor

Alignment & camber also needs to be vastly different for Daytona than pretty much any other track. IMO consult an experienced track/racing tire supplier and/or a shop that has extensive experience setting cars up for Daytona for the best advice.

Bill911

Buy my Hoosiers slicks, they are Continentials.

MariusRacer

I'm referring to the grand am spec conti . That tire is made for Daytona. As for Yokohama spec tires check out YouTube video of Dr Jim Norman. We have tried pretty much all tire manufacturers at Daytona. All blow eventually except the michelins and the conti GA. But hey if you want Hoosier go with that.

JoeMag

regarding comment below... same as other spings but metric: length/id/rate in units of mm / mm / N/mm

"I’ve also been told (But I don’t understand the numbers): Front 100/60/160 Rear 160/60/180"

converted spring rates are: 160n/mm = 913 lbs/inch and 1028 lbs/inch

JMon

Thanks. Comparatively speaking, is this considered stiffly sprung, or just normal for that car? I actually like the ride. It feels good except if you go wide in Sebring 17.
Now someone once told me that the stiffer the springs, the taller the tire needs to be. If I run too low of a profile, it may destroy the tires. Is that even an accurate statement?
Does the height of the tire in some way need to be matched to the spring rate?

boothkc

Here are some novice thoughts and I know nothing about Daytona....! I've tried Pirelli, Michelin, and Yokes. I like the Michelin the best and they are more durable than the other. Faster in my hands too. The Pirellis are my least favorite as they last the shortest and "go off" in mid session with an undesirable greasy feeling. Apparently better than prior versions though.

So we primarily run Michs starting from the "book baseline" set up unless in a Pirelli series. it's just to hard to learn and reconfigure the car for too many brands of tires. They are all expensive and the cost delta isn't a real factor given all the other expenses. So I think u are best off picking one brand and learning that as much as possible. My novice $.02!

Veloce Raptor

6 Cups can work very effectively with a wide range of spring rates, but yours is well within the effective range IMHO.

jrgordonsenior

OEM springs for 03'-05' 6-cups were 240f, 260r which equates to 1350/1500 lbs. Not sure abot the earlier cups but would imagine they're similar. Your rates are just fine....

As for spring rates and tire diameters, you should always run the taller 680 series rear tire for safety concerns. It's not just about banked tracks as the downforce exerted on the rear tires with your WHP and wing can overehat the shorter tires....

cstreit

This. When I attempted to run short sidewall R6's on my cup I *roasted* them in 4 heat cycles. Not exactly cost effective. Tall sidewall slicks are lasting 8-10 heat cycles before dropoff.

JMon

A lot of + for the taller tires. But why are series like Grand-Am running the shorter tires? 275/35/18s (640mm)