[foshjowler]

Came across this, and it seems exciting for the track guys more than autox. Possibly a Hankook RS4 competitor. I'll probably pick up a set for the Miata, and see how they do. Maybe do some back-to-back testing with the RT660.

https://grassrootsmotorsports.com/ne...ndurance-tire/

[davidwarren]

Originally Posted by foshjowler

Came across this, and it seems exciting for the track guys more than autox. Possibly a Hankook RS4 competitor. I'll probably pick up a set for the Miata, and see how they do. Maybe do some back-to-back testing with the RT660.

https://grassrootsmotorsports.com/ne...ndurance-tire/

This is what I’m waiting for too! The rt660 vs ECF.

[kropscamaro16]

no 20s no care lol

[foshjowler]

Originally Posted by davidwarren

This is what I’m waiting for too! The rt660 vs ECF.

Conti seems to be marketing them towards endurance racing, so I'd imagine the rt660 will have the outright pace over a single lap, but the Conti may be better for a 20-30 minute lapping session.

I've still got to get a roll bar in the Miata for track days, but I can do autox in it at any point. Also need to look for a cheap set of 15s locally that I can use for tire testing purposes.

[rotis]

Yea, I would liken this to a Conti/Hoosier "R7" type of 200tw tire. Probably not well suited to autox unless it's 100deg or something. Maybe they'll follow it up with an "A7" equivalent, like the original Rival versus the Rival-S.

[Mountain]

Originally Posted by foshjowler

Came across this, and it seems exciting for the track guys more than autox. Possibly a Hankook RS4 competitor. I'll probably pick up a set for the Miata, and see how they do. Maybe do some back-to-back testing with the RT660.

https://grassrootsmotorsports.com/ne...ndurance-tire/

It's probably a RS4/Supercar 3 competitor. The target for the tire is all the endurance series. It'll probably do "OK" for autox (better than the RS4), but wont be a RE71RS/RT660/A052. I have a feeling it will be a good tire seeing as Conti/Hoosier developed it.

[MatthewAMEL]

Really weird sizes in 19". Almost like they didn't look at the most popular fitment sizes for the target group. 295/315/325/345? But no 305?

[FNxR3DNECK]

Originally Posted by MatthewAMEL

Really weird sizes in 19". Almost like they didn't look at the most popular fitment sizes for the target group. 295/315/325/345? But no 305?

true but depending on how big/small they actually run the 315s or 295s could be comparable to 305s in something like the RS4 or SC3. For example the 315 Nankangs I'm running are in actuality the exact same width as my 305 RS4s.

[foshjowler]

Originally Posted by Mountain

It's probably a RS4/Supercar 3 competitor. The target for the tire is all the endurance series. It'll probably do "OK" for autox (better than the RS4), but wont be a RE71RS/RT660/A052. I have a feeling it will be a good tire seeing as Conti/Hoosier developed it.

Us autocrossers get enough 200tw love, I'm good with there being another track day/endurance tire. If they last like the RS4, I will probably go with them on the Miata long term as that'll be the track day car.

[foshjowler]

Originally Posted by FNxR3DNECK

true but depending on how big/small they actually run the 315s or 295s could be comparable to 305s in something like the RS4 or SC3. For example the 315 Nankangs I'm running are in actuality the exact same width as my 305 RS4s.

Also, if you can fit a 305, you can also go with either a 295 or 315, if not both. If the tire is good enough, we'll deal with the minor compromises of moving up or down 10mm.

[Mountain]

Originally Posted by MatthewAMEL

Really weird sizes in 19". Almost like they didn't look at the most popular fitment sizes for the target group. 295/315/325/345? But no 305?

Honestly, sure, at first I think it *looks* weird, but I think they made a very smart move.

Here's why: Everyone seems to do a 305, but that size ends up being a compromise more times than not on many performance-oriented cars, and most of the companies that do a 305 usually don't have other tire size options like a 295 or 285. Usually... A lot of cars that run wide front wheels have a 10.5", 10" or 9.5" up front. A lot of track-oriented cars have 10" or 9.5" rear wheels. A 305 fits fine on a 10.5", a bit questionable on a 10" and not so great on a 9.5". A 295 fits fine on a 10.5", OK on a 10" and a bit questionable on a 9.5".

Going with a 295 over a 305, if you have to pick one, you kinda fill more gaps than potentially leave. There isn't going to be a huge loss in grip 305 vs 295, but there is something to be gained in tire fitment with the 295.

295/315 will be a combo for the SS 1LE, PP2/Mach 1/GT350 crowd that will be just as good as 305 square or 305/315 and potentially be a better combo for steering feel, tire stability [on the wheel] and align better with the OE dynamic calibrations. For the cars limited to a 10" or 9.5" rear wheel (BMW or Porsche) 265/295. 265/295/315/325/345 are all size that fit Corvette, Camaro ZL1, GT500, Vipers...

[kropscamaro16]

anybody actually buy a set and use these yet>? looking at 2953019 3253019 to use with zl1 1le wheels

[N Camarolina]

Grass Roots Motorsport had a recent article where they tested this tire against other common 200 tread ones used for track days. It had slightly better grip, more consistency lap to lap and had less wear. Sounded like a winner to me - I think it's the best 200 treadwear tire they've tested to date.

Was just telling my friend about it. He's ordered a Mach 1 (Cup 2 tires) and was wondering about alternatives to reduce price of consumables. Looks like the tire is a bit cheaper than Cup 2, but more $ than F1 SC3.

[kropscamaro16]

anybody actually bought any and used them on their camaro yet?