[rocwandrer]

I just ran an event where the temps were mid 70's, and it rained all day, not pouring, but enough so my shoes were soaked in mere minutes. No direct sun. Some standing water. Conditions were at the point where people with slicks were agonizing over whether to run them or not.

I found the RS3's to be horrible. Horrible. Horrible. Hey, wait... edgy as heck, but there is grip there...

I was drifting the first two corners badly to get some heat in them, and then they had grip for the rest of the run. Turn the front wheels a fraction of a mm too far for the grip they had, and they washed out like I hit a patch of black ice, but stay at 99% and they had excellent grip.

There were 3 of us at the event that were on RS3's and we had similar experiences as far as having grip if you stayed under the limit.

Just thought I'd throw that out there since the conventional wisdom is to not even consider running RS3's in the rain. Evidently if it is warm enough, they work much better. Unfortunately, the rain pretty much instantly quenches them, so even back to back dual drivers are going to start with cold tires each run. I bet with heater blankets, they'd be a workable hot/wet tire.

 

[sldnrck]

My experience has been similar. 70 degrees or colder, rain, and windy they don't work. 70 degrees and rain they work, 70 windy they work. Once you get below 65, don't even bother irregardless of conditions. 100 degrees like this past weekend with pavement at 150, they work awesome. They will also overheat with two drivers at a pro, or local hot event in same run group.

 

[sxlostv1]

how much tire pressure are you running with the rs3's? hot or cold pressures?

typically you could lower the tire pressure by 5-10psi when it is rainy.

 

[sldnrck]

Ahh the old tire pressure question. I run 33-35 on my gauge. It typically does not read the same as other gauges but that will give you a ballpark. It you get too low the tires fell like they work better, but for me the response in slaloms is way too slow.

 

[sldnrck]

Since the edit does not work, I run that pressure cold and hot, check it after every run. I don't run different pressures for the rain, but I do soften the shocks.

 

[sxlostv1]

Since the edit does not work, I run that pressure cold and hot, check it after every run. I don't run different pressures for the rain, but I do soften the shocks.

next time it does rain, give it a shot at 5psi less. as for the driving, begin braking a little bit earlier and accelerate out of the corners a little bit later. on slaloms, keep consistent throttle, too much throttle will result in drifting.

 

[07HR350Z]

To the OP did you check the tire temps?

 

[sldnrck]

To the OP did you check the tire temps?

Not sure if I'm OP or not. I have run on the RS3 for several years on 7.5 inch rims, this is the first year on 8 and 9 inch rims. I have done multiple days of skid pad testing, and lots of events where I check the surface temps in three spots to see what pressures they needed. I have not noticed any difference in pressure needs switching to the larger rims. I'll stick by my range of pressures, hot, cold, dry or wet. I try and make the tire work its best, by optimizing grip.

To the previous post, reduced tire pressures in the rain seem like a band aid fix to not being able to soften the shocks. It's a good solution if you can't soften the suspension but if you can you do. The tire will get greasy with two drivers. The tire is horrible when cold. The tire is better brand new out of the box than old. Not sure any of that is new information though. If it is raining though I am putting on Toyos so I really don't care what pressures to run the RS3 at. I think there is zero chance a RS3 will beat a R1R in the rain.

 

[rocwandrer]

To the OP did you check the tire temps?

I did not. I had both probe and surface pyrometers with me, but didn't have time to do anything like that. I actually think based on the touch test that I wouldn't have gotten a real reading anyway. By the time I got out of the car after the run (10 seconds max), the temp felt the same as dead cold. definitely sliding/spinning the rear of the car a bit on the corner before/during the start lights gave them more grip than the front, but that extra grip was gone 2.5 minutes later.

 

[rocwandrer]

how much tire pressure are you running with the rs3's? hot or cold pressures?

typically you could lower the tire pressure by 5-10psi when it is rainy.

Track experience does not translate well to autocross when it comes to tire setups. One reason you run so much lower "hot" pressure at the track in the rain is that your "hot" pressures are actually read after the tire has cooled a lot. Another reason some people find this to be true to a greater degree is that wet air sees way more pressure increase when heated than dry air does. 10 psi less in the RS3 and I'd be just about scraping the wheels on the ground.... I will usually run a couple psi less in the rain if I remember because even though it is less grippy, it makes it easier to feel the limit. On slicks, I've run much higher pressures before runs where the rain has picked up to try to help clear water. No idea if it helped, too many variables in play.

 

[sldnrck]

I should add all my comments are autocross related. I did not even think about the pressures related to running on a track as I don't do that.