Stock rims for autocross?

[Siesta_Fiesta]

Really they bumped the mininum tread wear rating to 200 from 180?

 

[awwwww_shift]

Really they bumped the mininum tread wear rating to 200 from 180?

Yup, all street and street touring classes have a 200TW minimum at national events. I believe some local clubs still allow the 140TW stuff, but from my experience, the current crop of 200TW stuff tends to be as good if not better than the 140's.
re-71r's are top of the heap followed by the rival-s. past that it's the rs3(soon followed by the rs4 within a season), and the federal from what i have seen and driven on.
IMO, if you're looking to be top of the pack, the bridgestone is where you need to be, or the rival if you run primarily on concrete.
I'll be on the re-71r's to start the season, and may have a set of the rivals to run at national events on concrete(i.e. the nationals at Lincoln, NE)
keep in mind, this is at the pointy end of the stick. If you're just out to have fun, any 200TW tire is going to give you a good place to start getting used to autox.

ninja edit: looks like nexen may have a good option as well for us.

 

[Goingnowherefast]

The interesting thing is tire wear rating is basically dictated by the tire manufacturer. Hence why the RE-71R has a "200TW" rating wink* wink*

Yeah the new slew of tires are much better than older lower TW rating tires.

 

[30packdlg]

Can anyone give me the skinny on tire ratings? I'm trying to reasearch kinda confusing. Like what is the stock tread rating?

 

[enamelizer]

Can anyone give me the skinny on tire ratings? I'm trying to reasearch kinda confusing. Like what is the stock tread rating?

Treadwear rating started out as a scientific way to measure the wear properties of a tire, but has since been taken over by marketing departments and specmanship, making the ratings somewhat subjective. This is because the test only runs for 7200 miles, and allows manufacturers to justify higher ratings using internal test data on longer term tests.

Basically tires are tested in a convoy of cars, and the control tire is rated at 100. If a tire wears half as much in the test it is given a 200 denoting it should last twice as long.

The OEM tire (RE050) has a treadwear rating of 140.

 

[30packdlg]

Thank you so in scca you have to have 200 or higher? Or just 200?

 

[awwwww_shift]

Thank you so in scca you have to have 200 or higher? Or just 200?

For national level competition, you need to have a 200TW or higher tire to be legal in competition. IIRC there is a rule stating that oem tires are legal, so the 140tw re050a's that come on our cars stock, would indeed be legal(but much slower than the other tires out there).

 

[30packdlg]

Lower the number like 100 is softer and like 300 harder tires?

 

[awwwww_shift]

You got it. the higher the TW number, typically the harder the tire or longer it will wear.
Super sticky track tires are usually under 100TW, and your all-season(read: no-season) tires are typically 340 and up. I've seen as high as an 820TW(used to work at a tire shop for 8+ years) in my experiences.

 

[mykrrrr]

For national level competition, you need to have a 200TW or higher tire to be legal in competition. IIRC there is a rule stating that oem tires are legal, so the 140tw re050a's that come on our cars stock, would indeed be legal(but much slower than the other tires out there).

At the regional level, you can run below the 200 TW requirement IF you're on the OEM tire.

Also, IIRC...TW rating is pretty arbitrary from manufacturer to manufacturer.

 

[Kazz]

I strongly suggest checking with your local autocross group before walking in and claiming your OEM tires are OK for the stock class. Rules are different at local levels. Regionals and Nationals are known. Locals are their own thing.

 

[awwwww_shift]

I strongly suggest checking with your local autocross group before walking in and claiming your OEM tires are OK for the stock class. Rules are different at local levels. Regionals and Nationals are known. Locals are their own thing.

I agree. and for clarification:
http://cdn.growassets.net/user_file...4_section_13_street_category_b.pdf?1458856378

13.3.c.

C. Other
1. Any tire which is OE on a car eligible for Street Category may be used on
that car in Regional Solo? events. OE tires must meet all requirements
of Section 13.3 to be eligible for National Solo? events

so, if there are any questions about it, you can refer the local program to this rule.

 

[Andrew337]

I've been daily driving the stock wheels with 215/45 Hankook RS-3s and performed well autocrossing last season. I did three events with that setup and managed one class win and an overall PAX win. You can certainly be competitive locally with stock wheels and decent tires.

That being said, I ordered some dedicated autocross wheels for this season (16x7 RPF1 and 205/45 RE-71R).