I'm running into what I would like to think is a problem with the 04 Hoosiers I have.
I know they have to be warmed up to get sticky but by the time I'm done with my 3rd run they're just getting ready to stick good. Unless it's warm out.
This last weekend I ran a course that was 45 seconds for me. Temp was around 55* or so and overcast to partly sunny at times then would rain lightly between run sessions.
The tires would not really get as sticky as I would think they normally would. Per my pyrometer (I do realize it's not the best tool for this but it's what I have) the tires never got past 93* or so. I'm a bit discouraged because usually the first few autocrosses are overcast or rainy.
What I was hoping would be a good solution to this problem would be to buy some 15" wheels and Yokohama A032R soft compound tires. And use these just for overcast and rainy days. Does this sound like a solution or am I going to run into the same problem with these tires as well?

what size are the tires you are running now? have you tried dropping the pressures to see if you can get more temp into them that way?

I did try that but maybe I didn't start low enough. I know the 04 Hoosier needs a bit more air than the new R compounds but I started at 35 front and rear.

What are you doing to retain the heat you built up in your tires between runs? Do you have covers to put over the wheel / tire to hold heat in? If not, you can make these relatively cheaply... and they are legal in SCCA Solo competition.

As a data point, I was only getting the outside edge of my V710s to about 125 degrees (taken 45-60 seconds after completing a run on a ~50 second concrete course). Air temperatures were around 70 degrees. Cold pressures were 39 psi in the front (where I was measuring) and hot pressures were only about 43 psi.

I've run Hoosiers in similar conditions to what you describe and I couldn't get them into the triple digits on a short concrete course. It's very tough to get them up to temperature when it's cool out.

Yeah I thought of that and maybe that is what it comes down to. Well obviously I didn't think of it enough.:confused
That's the first thing I'll do next, thanks!

Edit: I have 710's waiting in the wings for these to die.:)
Thanks for that last input as well. Pretty much confirms what I was thinking.

Options that come to mind, since lowering the pressures hasn't helped enuff:

1. Co-driver. More runs = more heat.
2. Different Rubber. Although I wouldn't consider the Yok's you mentioned as a step in the right direction, but that's just me. Put the V710's on now, and you'll be amazed at the difference.

Options that come to mind, since lowering the pressures hasn't helped enuff:

1. Co-driver. More runs = more heat.
2. Different Rubber. Although I wouldn't consider the Yok's you mentioned as a step in the right direction, but that's just me. Put the V710's on now, and you'll be amazed at the difference.

a co-driver (aka tire warmer) would most certainly help. Then get those tire covers to retain the heat generated since you'll have to wait 5 min between runs...

Double driver...good idea. Will do.

Will the 710's need as much warming up as the Hoosiers during cool days though?

In two months when it's hot some will tell you to spray water on them because it's too hot. Keep that in mind.

Last few I did were on ancient Toyos and it was cold out. It was a rough deal getting them warm even with another driver. An insulator is nice if you can do it but another trick if the sun is not out to warm the pavement is to drive as little as possible between runs. The cold pavement will take heat out of the tire. I.E. take the short way through the paddock back to staging. Remember to try and take advantage or minimize loss with what nature gives you.