Wet race day, what tyres...
 

Well, looks like we may be in for a rainy day tomorrow for the first meeting of the season...

Dilemma....

What is likely to be a better wet tyre/wheel combo?

New set of Dunlop Direzza 03g 205x50x15 on 15x7

or

New set of Nitto NT01 225x45x15 on 15x9

anyone care to comment or hazard a guess...?

I worry that the wider tyre won't clear water enough but don't really know either way....

The Nitto have a compound similar to R888 if I'm not mistaken. A compound that is well known to keep some grip and predictability even when wet.

I have no experience with Direzzas but the compound plays a much bigger role than thread pattern (the thread volume is much more important) in my experience, the track is not only puddles all the time even at "wet race".
This is based on sprint racing (15-20 min) where changing tires is out of the question and lineup etc makes me decide about 30 min ahead of time (so an intermediate is the lazy mans choice).
Finishing third gives more points than being first into the gravel trap.

I have used NT-01s on a cold, wet track and they are fine if they have most of their tread depth left (mine were new at the time). They are still predictable and have surprisingly decent grip.

For a rain only tire there are better choices with more grooving, but for dual-purpose the NT-01 is fine. RS-3 would be another option. Do you have a set of wheels for rain only?

Hoosier wets

+1. Hoosier H20s are going to be 6-10 seconds a lap faster than a full-tread street tire in the rain. It's a little spooky how good they are in really awful conditions.

+2 on Hoosier wets...and I have a sticker set for sale

Thanks guys, class is limited to dot tyres. I have a set of 7" rims with a set of new dunlops I had designated for wet use until they wear then was going to move over to dry use and buy a new set for the wet rims again....BUT committing to a set 15x9's has changed my options.

Thanks for the advice. Looks like it might be semi dry after all but showers are predicted towards the end of the day so bit of a lottery at this stage.

I have raced on full wet motorcycle tyres and I agree the grip is quite unbelievable, i presume a similar storey on 4 wheels with wets. I was going to say unfortunately but I think havinG the DOT rule is probably a good class rule. keeps the costdown (i think).

I had my Nitto NT01 on when they were almost down to nothing left. I thought it was going to be slippery when it rained, but they hung in there with more grip than my street tires.

Might be semantics....but the H2O wet is a DOT tire.

Well, yeah, duh, wet race tires (Hoosiers, whatever) are a no-brainer if you can do it. I inferred from your original question that you were not looking in that direction.

I did a few TT sessions on half worn NT01s in damp conditions. surprisingly they were predictable.

it was fun for competing during rainy conditions since ive never done it before, especially out here in AZ. learned a lot QUICK.

Damp = A6 or NT-01
Really wet = H2O, full thread NT-01 or 205/50/15 R1R on 15x9

If there's standing water H20, if its sopping wet but with big puddle on line, H2O. If its sopping wet but no big puddles on line, Slick. If there are puddles on line but also dry spots on line Slicks. Driving slicks in the rain is part of becoming a man.

My current choice of tires for the miata are 275 A6s or 225 RS3. I'll run the A6s even if there is 3" of standing water everywhere, unless the course water temperature is at least 100*F or higher then the RS3s might be okish. So unless I'm trying to race in a hot tub I'd rather run slicks than RS3s even in standing water, RS3s suck that much in the wet (actually its a temperature issue, IE if the water was 100*F the RS3s would be astounding).

How are the Hoosier wets on partially wet to dry conditions? Why I'm asking is that I know when Formula 1 wets get in to drier conditions they deteriorate quickly.

Yes that is typical. Same thing with bike rain tires. The compound is very soft, and the carcass is designed to generate some heat. So if they are not cooled by water, lots of water, they overheat and deteriorate very quickly.

I personally saw someone destroy a set of rains in an 8 lap sprint race, from brand-new sticker tires to junk. The track was damp with no standing water. The tires were very fast for the first few laps, but then the tires inevitably overheated and they became slow quickly. At the end of the race the tires were toast.