89474 205/50ZR15 86 W BSW 200 AA A 5.5" - 7.5"

Tire rack won't mount them on a 8 because BFG says the max is 7.5. I'm 99% sure that's a recent reword, I'll check my catalogs at work tomorrow, but I think it used to say "recommended rim width" not min/max rim width.

Our fast and hard rule is we'll put a tire on a wheel 1" wider or narrower than recommended. No more.

I ran mine at 26psi cold at the autox. They never warmed up enough to be hot to the touch. With the sidewall as stiff as it is, and if you're running a 205 on an 8" rim, I don't think anything over 30 would be necessary. In for test results, though.

So, consensus is I should keep my 195 R1R's instead of buying a set of these?

Depends on what you want. If you're looking for the best cold/wet rain autox street tire, 195R1R is still the magic it seems. OTOH, the Rival will almost certainly wear much much better under track conditions.

^Yes, only in relation to STS autocross. When I jump to CSP, I'm poor, so locally I'll be running street tires as well it seems. (save teh purple crack for ProSolo's)

That's funny because TR sent me my 15x8 K1's mounted with 205 Rivals lol

talk to Rudy

https://www.miataturbo.net/attachmen...ine=1368287849
https://www.miataturbo.net/attachmen...ine=1368287849

Whoa whoa whoa....I thought you could only 15x7's now?!?!

nope. kosei k1 version2.
15x8+35. I just got a set. :D

https://www.miataturbo.net/attachmen...ine=1368557607

Guess I'm buying wheels soon....

yup.

search for NB Miata, SCCA STR class and there they are. a little on the heavier side for an 8

Long Term Update?
 

Any update after running them for a while?

I just read over at miata.net that these have stopped being produced until the spring?
I guess I'll have to put 225's on my 15x8"

Ran z2s at the track, 100 miles on track. Looks new, mild greasyness on a 85 degree day. Unsure of track temps. Happy with my decision

Speaking of the above, I have 185's on a 7", and if I were to do it again, it'd definitely be a 7.5".

Section width on them is 7.6".

Can't agree that 195 and 7.5 go together. Their section width is 8".

I've had 225's on 7", and it was like turning with using marshmallows.

I've been happy with them. As a highway tire, I took a 360 mile round trip up to Packwood a couple of months ago and have no complaints.

Today's autocross was wet. In the first run group I believe I was top time in my class. The second run group got 2 runs on an almost completely dry course before it dumped rain on them, so times came down drastically compared to the first run group, but comparing the after-rain runs for the second run group (which is easy to do when you're running the timing computer) my time was still competitive.

I'd do it again.

These tires are shit in the rain on a track. I was able to drive faster on cording ra1s in standing water than I was able to on full tread rivals. Not to mention(I'm sure möbius will chime in since it was his set that I was driving on) they are losing chunks of tread and had splitting across the tread all over.

Well, I just mounted a set of these (I think I got the last 205 set available from Phil's). Holy cow are they stickier than the half-worn 340 treadwear old-tech G-Force Sports I took off. This is really my first experience with this class of tire. Can't wait to get these on track.

My HPDE instructors were hating those old street tires. I got everything from niceties ("These tires are great teachers -- feels like you're driving in the rain") to brutal honesty ("These tires suck -- I hate them"). LOL.

OK, time to make fun of the track noob. ;)

Z2s perform much like the Z1s in the rain: M A G I C (for street summers).

Is there any part of the design of the "tread" on these tires that makes you think they will do any better than abysmal in standing water? The only thing they have going for them in this regard is a high silica compound. None of the grooves look like they're designed to evacuate water. This is very clearly a dry competition tire.

Wet tires tend to look like the Hoosier H20, with diagonal grooves for water evacuation and a deeper tread (9/32nd on the H20, vs 7 on the Rival).

Im aware that they aren't designed for serious wet use but I drove the rest of the day on cording ra1s with no tread at all and those performed better I would think a tire with at least some tread would be able to move a little more water than a bald ra1