autox tires for 2014

Scott Johnson · **Posted:** Wed Nov 13, 2013 5:53 pm

My Dunlop Z1 tires still have a ton of life, after 3 track events one autocross school and about 7 autocrosses (most 2 driver).

How much time am I giving up to the new crop of tires?

Jason Mauldin · **Posted:** Wed Nov 13, 2013 9:30 pm

JamesShort wrote:

Jason Mauldin wrote:

Honestly, I question whether any of the 275 street tires are good enough for a mustang.

The car is really heavy and the only way around that is with big sticky tires. I might be wrong, but I don't see this car ever placing at nationals in a class where you are limited to a street tire.

How does Chuck's E90 M3 compare? It's 3200ish lbs and has 414hp and 300 lbft of torque and he's running 245 Rivals all around and he's plenty fast on that setup

.

The mustang has less hp, more torque, weighs 200-400lbs more, the suspension is not identical and the mustang probably doesn't have as good of a weight balance, so I'm not sure that there is a true comparison there?

However, if I take a quick look at the pro-solo results from last year, I don't see any e90 m3s that did well in the st classes? So my statement might hold true for them as well?

Matt McGrain · **Posted:** Wed Nov 13, 2013 10:40 pm

Rivals > * and don't look back. I can't wait to try out mine this weekend at Cherry Point. No baby showers ftw. :lol:

Patrice Bousquet · **Posted:** Thu Nov 14, 2013 9:29 am

Scott Johnson wrote:

My Dunlop Z1 tires still have a ton of life, after 3 track events one autocross school and about 7 autocrosses (most 2 driver).

How much time am I giving up to the new crop of tires?

With the time you did last Saturday it doesn’t look like you are giving up that much. When you will get outside of the top 10 Pax or I beat you with the Abarth :wink:

then I will consider it’s the time to change tire, not before that.

Chuck Branscomb · **Posted:** Thu Nov 14, 2013 10:51 am

Jason Mauldin wrote:

JamesShort wrote:

Jason Mauldin wrote:

Honestly, I question whether any of the 275 street tires are good enough for a mustang.

The car is really heavy and the only way around that is with big sticky tires. I might be wrong, but I don't see this car ever placing at nationals in a class where you are limited to a street tire.

How does Chuck's E90 M3 compare? It's 3200ish lbs and has 414hp and 300 lbft of torque and he's running 245 Rivals all around and he's plenty fast on that setup

.

The mustang has less hp, more torque, weighs 200-400lbs more, the suspension is not identical and the mustang probably doesn't have as good of a weight balance, so I'm not sure that there is a true comparison there?

However, if I take a quick look at the pro-solo results from last year, I don't see any e90 m3s that did well in the st classes? So my statement might hold true for them as well?

I don't think anyone has thought of running an E9x M3 in STU. A good driver finally showed up in F-stock with an E92 M3 at Nationals this year and could have won the overall; I think he placed 4th on the first day and he had F-stock FTD on day two, ended up getting a 3rd place trophy, 3/10ths back from 1st.

The E90 M3 with no sunroof, no fold-down rear seats (like mine) actually weigh closer to 3540lbs, *not* 3200ish. I don't know what the Mustangs that have dominated F-stock weigh, but they're probably in that same range? One nice feature (at least for me) about the V8 in the M3 is the super flat and long torque curve that allows you to really put down power. The 5L V8 in my M5 has a bit less peak power (400) but a fat torque curve (369 peak), and it just loves to spin its rear tires any chance it gets -- takes a lot of careful throttle use on course. Conversely, the M3 torque curve is flat and power just rises and rises as rpms rise into that crescendo between 6000-8300.

245 Rivals all around since that was all that was available in Feb. I have no clue what to do when replacing them. With 8.5" and 9.5" wheels, the 245s in the rear are stretched and feel really tight and communicative in transitions. I could go to 275/35s all around (same diameter as the 245/40s), but then I'm worried of a less than desirable change up front stuffing that 275 onto a non-spec range 8.5" wheel. I think Rodney and me need tire testing funds to fall from the sky so we can rent Tire Rack's track.

Andrew Jonell · **Joined:** Mon Mar 23, 2009 6:43 pm **Posts:** 1350

Scott Johnson wrote:

My Dunlop Z1 tires still have a ton of life, after 3 track events one autocross school and about 7 autocrosses (most 2 driver).

How much time am I giving up to the new crop of tires?

According to Dunlop and Tire Rack, about 1%.

http://www.tirerack.com/tires/tests/tes ... p?ttid=168

Chuck Branscomb · **Posted:** Thu Nov 14, 2013 11:20 am

Andrew Jonell wrote:

Scott Johnson wrote:

My Dunlop Z1 tires still have a ton of life, after 3 track events one autocross school and about 7 autocrosses (most 2 driver).

How much time am I giving up to the new crop of tires?

According to Dunlop and Tire Rack, about 1%.

http://www.tirerack.com/tires/tests/tes ... p?ttid=168

...on fresh vs fresh tires.

Andrew Jonell · **Joined:** Mon Mar 23, 2009 6:43 pm **Posts:** 1350

Heat-cycled tires are going to perform noticeably worse. It was just a old vs new compound comparison.

I'm not sure if I'm just hard on tires, but I find that I heat cycle the tires before I hit the wear bars. I can't complain too much because summers are only $4-500/set (or closeout on 14" Azenis for $240 haha).

Scott Johnson · **Posted:** Thu Nov 14, 2013 11:51 am

Andrew Jonell wrote:

http://www.tirerack.com/tires/tests/tes ... p?ttid=168

Doesn't sound like much until you say "1 second on a 60 second course." One second is an eternity.

Les Davis · **Joined:** Fri Aug 29, 2003 2:04 pm **Posts:** 2059

So, I'm actually thinking about running my Cobra on street tires at events down here next year and have been looking at the current crop of tires. I want to run 17" wheels mainly for expense the problem I'm seeing is that all the top rated current crop of "extreme" street tires stop at 255 section width for 17s. I can go wider if I go up to 18s which is an option as I plan to buy wheels too, but that significantly increases the price of the wheels and tires. 255 is the stock sized tire for this car, and I was hoping to at least run 275s as that is the stock size for the Cobra R. The only tires that offers wider sizes in 17s is the Kumho XS which from what I'm reading is not quite as good a tire though someone did beat me running them this past weekend so they must not suck all that bad. With the XS I can go as wide as 315s, I'd be mounting them on a 17x10.5 wheel, and I'm pretty sure I can make this work on the car without too much rubbing, there are also 275 and 285 options in the XS. So my question is, even though the XS is slower than a Rival when compared in the same size, would not a 315 XS or even a 285 XS be faster on a heavy car than a 255 Rival?

Scott Johnson · **Posted:** Thu Nov 14, 2013 1:26 pm

Original Dunlop star spec in 265/40-17, but that's probably off the pace of the 255 width in the newer tires. Toyo R1R can be had in 275/40-17, but they aren't supposed to like the heat, so be prepared to spray them a lot.

Steven Carter · **Posted:** Thu Nov 14, 2013 2:24 pm

don't necessarily go by section width, but treadwidth--and pick a treadwidth within an inch of wheel width.

Matt McGrain · **Posted:** Thu Nov 14, 2013 3:20 pm

I read somewhere that the new ZII's & Rivals are just as quick at full tread depth as shaved. Anyone know if there is any merit to this?

Zach Hill · **Posted:** Wed Nov 27, 2013 11:15 am

Chuck Branscomb wrote:

So as autocrossers, we all have to be mindful that "the answer" to what is "best" really doesn't exist. We will only know that answer for any particular one of us if we actually test the top three tires on our car, with the wheel widths we use, on the courses/tracks we normally use. If we're going to nationals on fast concrete courses, our tire choice for top performance is most likely not the one that will perform the best on the wicked sticky unsealed asphalt at NCCAR.

Jason Mauldin wrote:

Chuck has a point, but an underlying theme there, is that the tires are so close to each other, that perhaps chasing the best isn't worth the hassle. Pick one of top three that seems to meet your needs the most and don't look back.

What these guys said. :thumbsup:

I'm not a slow autocrosser, but I'm not the fastest either, and it is humbling to say that I couldn't really tell a difference between the RS-3 and ZII's I ran in 2012 and 2013, respectively. The only caveat to that is wet and cold performance, where the ZII was noticeable better (but they do cost more). But grip levels in the dry? They both rock. :whoknows:

Like Jason says, pick one and don't look back. Drive the crap outta them until you burn all the tread off. While tires are arguably the most important part of car prep, it's not fundamentally different than any other type of prep: the best performance mod you can do is tighten the nut behind the wheel. With all the great street tires available now, the performance difference won't be more than a couple percent between them, which is far less than most of our skill variance between runs.

JamesShort · **Posted:** Wed Nov 27, 2013 11:25 am

I'm still an RS3 fanboi....cheap and fast (and I put almost a year of learning their odd limit/slip angle characteristics so I don't want to relearn another tire). It seems that GRM/Tirerack are putting them on the backburner, but I really don't think the new gen EPSTs are any faster (defintely not like the 615 vs (Star Spec Z1* | RE-11 | Kumho XS) back in the day).

THSCC Forums

autox tires for 2014

Who is online