It's nice out there, I'm going for a drive.

 

+1...but I've kept the winter shoes on because the ground is still cold and the air temp is very cold today. Way too early for summers IMHO.

 

Ahhh, went for a drive, feeling much better now.

Saw a Dodge Viper out, also saw a blue 991, there was a Ferrari that went by my street yesterday.

But the cops are also out nabbing people too.

 

I'll be sure to do that if I run across him.

 

I spotted a Ferrari Testarossa driving north on the 400 yesterday as I was coming back from Barrie.

Also spotted quite a few of the new Corvette. Nice looking car...

 

There is some college kid near me who drove his new stingray all winter!

 

haha...I drove my 991 all winter!

 

How was it overall? Did you take it up to Blue? Was height clearance ever an issue?

 

It was fine. Threw a sandbag in the front luggage well as the front end felt a bit floaty but for a rwd 911 she handled fine.

At Blue the car was fine so long as I never went too fast. Its stock ride height so no issues in the snow really. Had it been lowered then it would have been an issue as my prior C4 was (snowplow).

 

I put the summer tires on my cayenne s last weekend

 

Assuming we're actually talking about true summer tires . . . .

Temperatures should be consistently above 5 degrees C - that's where they're designed to operate.

you're going to ruin the compound if you expose them to freezing temperatures - they can crack, etc

and they're going to be hard as rock in anything below those temps anyways, rendering them functionally useless.

 

I usually put my car back on the road in early March. Obviously not this year. But I don't agree that the tires are useless or in danger below 5 degrees C. I've driven Michelin PSS and PS2 for days in temperatures below 0 degrees. Traction is definitely reduced but not nearly as significantly as I had expected. I'd compare it to driving in heavy rain. You need to be more careful, but I'd bet that the traction is still above the average car's.

Traction on any snow or ice is brutal though.

I've never seen any real facts on the subject though. Just comments like "summer tires shouldn't be used at temperatures below 7 degress". Has anyone found a graph of friction vs temperature for any sample summer tire?

 

Read the manufacturers suggested operating ranges.

More importantly, as I mentioned, if the compounds freeze the tires can split and crack - they're not designed for anything below freezing.

Corvettes had a huge issue recently with their tires degrading when customers simply moved the car in sub-zero temps, not even really driving them.

That's why the manufacturers warn you to store all summer tires inside during the winter to avoid freezing temperatures - it's right on each of their legal disclaimers when you purchase the tires and also on the descriptions on Tire Rack.

 

Good point. I wasn't aware of the issue with the Corvette's tires cracking in the cold. I spent a few minutes reading and I agree that it would be a big concern. That does look like an issue with a specific tire though (Pirelli) and it isn't a common problem. I know my Michelin's have been in temperatures well below freezing for long periods without any issue.

I realize the manufacturers don't recommend running summer tires in freezing temperatures but I think the impact on traction is overstated. I know on my Michelin PSS the drop in traction is (just) noticeable but it isn't a huge problem. Obviously not a good idea to push the limits of the car at all in those temperatures and it clearly isn't ideal. I suspect the impact varies pretty dramatically between tire vendors and models though.
I'd still love to see a graph of friction vs temperature

 

Well, I did run for 14 hours at Watkins Glen in sub-zero temperatures on ZII Star Specs . . . . including in the snow.

That was an interesting race.