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NASA TT rain tire rules

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3-5 Years
Gilbert SC
If it is raining during a NASA TT event is it ok to swap to a rain tire let’s say I’m running Toyo RR and have declared that on my car class form but rain starts and I swap to something like a Faulken RT 660. Do you have to resubmit the car class form, and can you do that during the middle of an event?
 

Bill Pemberton

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Great question and something you might want to check with your Region. Ours Region is pretty reasonable, but it is in your best interest to check. Your times won't be as fast, anyway, unless the entire weekend is rain soaked. You can usually chat with your Race Director about things like that, though if you were racing in a Spec Class , it is more defined and you would need to run a specific brand's rain approved tire/
 

PaddyPrix

If breakin' parts is cool, consider me Miles Davis
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So in your example, and going by the current tire classifications by the Super Touring 1-4 rules, if you're starting the day off with +1.6 Toyo RR tires, and that's what you've got with your submission form, chances are you can't trade up to a +1.0 Falken RT660, as it's perceived to be a better tire by the mod weight. Let's say that in one of your sessions, the rain dries up, then you're on a much faster tire in much better improved weather, and you just stole a 0.6 point bonus that you kinda didn't have to start the day.
Let's try that from the other way though, if you had started/declared running on Hoosier A7 (+0) and went down to a Falken RT660 (+1.0), you're technically going to a slower tire, which should be fine, as you're not going to bust out of your class power/weight ratio by going to an objectively slower tire, and the second the track dries up, you're definitely going to want to switch to the A7 just because times matter.
In SoCal, you need to have your submission form (if it wasn't previously submitted) ready to pass in to your leader for the morning driver's meeting, or at worst, get bumped to TTU. After that, the rule is one car/team per class per competition day. So, I can't run it in TT2, and you take it later and run it in TT3. Pretty sure that applies to all since our TT Director also was the Nat'l TT Director, and Greg was a stickler for the rules, as he was one of those writing most of them. For what it's worth, we're also starting to really push the tire brand/compound checks along with the metal tire template tool during impound, I was doing that our previous weekend in addition to the random size spot checking.
 

Bill Pemberton

0ld Ford Automotive Racing Terror
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Blair, Nebraska
Much better explanation and I should have listed the fact that the rain tire had to be in the same tire classification as regularly used. I do believe in areas where it rains often there is a bit of flexibility as one can't run to the TT Director with a new forms at the last minute. I would carry a second sheet in the car as it is likely cars will run through the scales and that can be handy if they want proof. Since you will have one or two TT Race Meetings each day procedure can be asked then.

Great explanation Paddy Prix and I am sure all appreciate a much better answer than my original one -- thanks!
 
37
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Gilbert SC
Thanks for your replies. I have a TT this weekend with rain in the forcast, so I think I will go with the ask for permission in the morning meeting plan. My tire issue comes into play because even though in my reference the Faulken is a "faster tire" than the RR, I still fit into TT3 even with the Faulken. So they are different class tires but with either I am still in TT3 class.
 
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PaddyPrix

If breakin' parts is cool, consider me Miles Davis
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Thanks for your replies. I have a TT this weekend with rain in the forcast, so I think I will go with the ask for permission in the morning meeting plan. My tire issue comes into play because even though in my reference the Faulken is a "faster tire" than the RR, I still fit into TT3 even with the Faulken. So they are different class tires but with either I am still in TT3 class.
Last year's Nationals turned into a big mess as it did rain, and it actually decided a few of the championship races with off-on rains and some people making guesses on what to run with, since we're not running with full pit crews and pulling off sub 10 second pit stops, but the Toyo RA-1 is in the same class as the Toyo RR, and the Hoosier H20 isn't listed just like the A7/R7, making it a 0. There's a little leeway in regional stuff though, not everybody has those deep nat'l pockets, but just because it's raining doesn't mean you can take all your ballast off/out or start changing the tune and upping the power to more favorable allowances, which is why you're generally still bound to your original classing sheet. You wouldn't believe how many people cheat on the littlest of things too, which is why the rules on tuning get so complex and difficult, because some aftermarket devices can do it almost instantly, local and wirelessly, and we can't just go randomly pull/swap ecu's like in a Spec class.
 

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