S550 Which tire on a cold track?

[RedStallion27]

It looks like Road America will be pretty chilly this Friday. Below 40F at the start of the day with a late afternoon high around 50F. It will also be windy with 20mph sustained and 36mph gusts.

The track may be wet from rain the night before, though the rain is forecasted to slow after midnight and completely stop around 5am.

I have Falken RT660 and Conti ECS02.

Which tire would you use?

 

[blacksheep-1]

That's a really broad request..whichever is stickiest, I guess. The biggest issue will be to obtain the hot target psi, so take a guy with an air tank down to pit road, runa about 10 hard laps, bring it in hot, and set the pressures there.

 

[GAR944]

I'm assuming you have the option of only taking the set you put on the car. If so, then are you a gambling man? Do you trust the weather bureau saying the rain will stop? If it does great, the track will dry quickly with use with that amount of wind. Well the part that's used will, going off line may be exciting it you need to pass or make a mistake.

First issue is can they take the cold in general. You be the judge with the below information.

No temp info on the Conti, but you get to see my shortcuts

Had a similar dilemma but i had the ability to take both. Had to buy a set of rims that fit over the GT350 brakes i run so i could get road tyres. Caught on the grid with everyone else when the rain arrived early with 305 width CRS's on the car. 140kph (87mph) and aquaplaning. Put on stock 255/275 Michelin 4S and 180kph (112mph) before i chickened out as i needed to brake. Thats where the next fun bit comes in, locked a wheel at that speed with gentle braking, Pagid pads RSL29's overpowering the available grip at that speed.

Its not a competition day, you are risking your toy, my single tyre choice given the known weather would be the one with the best wet performance. You can always have fun in the dry on an all weather tyre, the opposite can't be said.
My other bit of advice is don't be too gentle initially. To get temp into the tyres you have to load them up, when the location is right, test your hard acceleration and braking. Find the grip limits at a low speed and straight line. Get heat into brakes that then heat the wheels. Find out how gentle you will need to be later by being a "little" bit silly safely earlier.

 

[Junkyard Dog]

locked a wheel at that speed with gentle braking, Pagid pads RSL29's overpowering the available grip at that speed.

Does ABS no longer work when you put racing brake pads on the car?

 

[stevbd]

I think I would use the Conti in that situation.

 

[GAR944]

Does ABS no longer work when you put racing brake pads on the car?

Putting AI to work so i don't have to type it out.
The main takeaway is in the last line.
On/Off Feeling: Paired with low-grip wet road tyres, the window between "slowing down" and "triggering full ABS lock-up prevention" becomes incredibly narrow. You will have to be exceptionally gentle with your foot to avoid constantly triggering the ABS.
My first brake application was me trying to find that gentle limit, it was really low, i lifted instantly but still had to deal with a car slightly fishtailing at that speed and still get back on the brakes for the corner.
You can see me crap my pants then have a stern talking to myself just after the 3 minute mark on the first flying lap.

 

[Stan Whitney]

Conti I think too. The RT660 is a bit cold natured, and the Conti, if it's dry, will be ok in the cool temps, and excellent if damp or wet.

 

[RedStallion27]

I'm assuming you have the option of only taking the set you put on the car.

I will have both sets. I’m driving to the track on the Conti with plans to install RT660 at the track.

Maybe I’ll just wait and see what the track looks like that morning. If it’s wet/cold I’ll leave the Conti on the car until it (hopefully) dries/warms up.

 

[Junkyard Dog]

No fair! You didn't tell us "both" was an option!

 

[RedStallion27]

No fair! You didn't tell us "both" was an option!

Yeah you’re right. My primary question, which I didn’t communicate very well, was:

Will the RT660 be unsafe or be damaged on a fast 40F track surface?