Is there any point to shaving street tires for autocross?
Or is that something to consider only when going to something like Solo I where you reach much higher speeds.

 

The only really good reason that I would shave tires would be if I had a big event (like National Championships) and I had to be new tires just before with no chance to scrub them in.

But there are some who do shave their tires....and it's usually BFG KDs (Mega$) or Bridgestone (also $$$), and not the cheap Azenis.

If you were road racing, and not just hot-lapping, and you had to run street tires (due to rules), you would want to shave the tires. Doing so would actually increase the life of the tire (as full tread tends to chunk if it gets too hot, except for Azenis, which just get slimy). The Speedvision cars (which had to run Toyo T1-S) all shaved their tires to 3/32".

 

Thanks guys
Still trying to decide what tires to run this coming season.

 

Done much autocrossing before?

If you're a relative newbie, get Kumhos or maybe Toyo Proxes RA1's (not common in autox circles, but they're actually pretty good tires and they're very long lasting). If you're an expert, get Kumhos if you're on a budget and aren't out to win Nationals, or get Hoosiers if you're ready to spend more money and win the big events, but don't mind going through 2-3 sets per season.

FWIW, I'm on a budget, so I'm running street tires. Might get me some stickier ones though.

 

I did about 10 or 12 events last season and came 5th in class for the regional series here in Ontario (not exactly a big achievement but I did the majority of the events on the stock all-seasons on my Protege5 at the time). Still have a lot to learn but I'm not a complete noob. Actually I have to work on being more aggressive I think because I tend to drive a line that is too clean and not the ideal one. (I was still learning the dimensions of the car too since I only got it a few months before starting to compete and wasn't driving very often at the time).

The two best guys from the class last year are both moving up a class I think so it will be basically me vs. two other guys who were novice along with me last year. One has r-compound tires, I don't think the other does .. but might come Springtime.

I don't want to get Hoosiers or Kumhos at this point.
Hoosiers because they are too expensive and I cannot run the proper camber so will destroy them prematurely.
Kumhos because of the camber issue, plus less than stellar reports about their performance from other people racing last season.

I'm still considering RA-1's but Toyo says to run 2 degrees of camber which I don't think can be done on the MP3 stock.

Also, I am hopeful of the new compound for the Yokohama A032-R because I hear they can hold up better to camber-deficient cars. But they don't make that many sizes .. I will have to get 15" wheels for them unless they have added a new 16" size.

At the moment I have two sets of summer tires sitting around off rims - 16" A520 and 17" SP9000. Either of which I could have shaved for $25/tire.

I need to get new rims no matter what tires I get but I need to find a good balance of size, weight, cost, durability, and competitiveness.

--
edit:

I just checked the 16" sizes and that may be the way to go for now. Even if I don't end up getting an r-tire I could maybe shave the A520s and run those, then move to a 225/50/16 r-compound later on.

 

A few comments on the last post...

The old A032R's hold up well on camber-challenged cars because they're hard and slow. If you really, really need a long-lasting tire and don't think you'll face real competition, feel free to get them; just don't expect to win any big events. Almost nobody at the top levels of autocrossing or road racing uses these tires, and for good reason- they aren't very grippy. I have driven on them before, and I was very underwhelmed. They ARE faster than street tires, just not as fast as REAL race tires.

The new A032R? I would wait and see if any of the top drivers like them before buying them. Given my dislike for the original A032R, I think the jury is still out. We'll see.

As for the problems of having inadequate camber for the tires to work properly... welcome to the world of Stock-class racing. You WILL wear out the shoulders first when you're racing a camber-challenged car. Deal with it. Your competition is dealing with it too. Don't panic because the manufacturer's literature says you need camber. However, camber limitations ARE a good reason to buy the Kumho Ecsta V700 (not the Victoracer) or Toyo RA1 because they can be remounted inside-out to equalize shoulder wear (Hoosiers and Victoracers cannot).

I'm also a bit puzzled about the negative comments about Kumhos, because they are REALLY quick tires that earned numerous SCCA Solo II National championships. However, I think I can probably explain the problems... the new Ecsta V700's need a lot of tire pressure, MUCH more than the old Victoracer V700's needed. The Ecsta V700 is a new-for-2002 tire, and it took numerous events for some of the top drivers in my area to figure out that the pressure requirements were different. Could be that your local guys still haven't figured it out.

 

pseudo beat me to it. I've known several people who've run reverse-mounted victoracers with good results.

I'm also surprised at the negative comments about the Kumhos. I've got a set of victoracers, and they grip like mad. I've driven on the Toyos, and found them noticeably less grippy. Reportedly they do last longer than the kumhos, though, so for a budget-minded racer they might be a good option.

GRM's tire-test showed the Toyos to be only a few tenths slower on a 60-second course, IIRC.

 

Well I would like to be competitive .. which means RA-1 or V700. Or gamble on the new Yokohama ... it kind of depends what everyone else in my class will be running and I think at the moment I am against those two tires. I don't need them to last more than a season really. This will be my most expensive year because I have to get wheels as well as tires, and after that I can pretty much handle buying a new set every year or year and a half...

The negative comments I have read from local people are about the Ecsta, not the Victoracer. I think there was a bad batch shipped to Toronto last year because a some people had to get tires replaced after one weekend of Solo I competition or something like that ... other things I have heard is that the Ecsta sidewall is not as stiff as people would like although I'm sure it is way stiffer than any street tire. Not everyone dislikes the V700 but enough people that it makes me lean towards the RA-1.

time to shop around ...

 

Some folks in my area have told me that the Victoracers don't work as well reverse-mounted. YMMV I guess. However, I WAS wrong about the Hoosiers. I don't know what I was thinking. Guess I drank too much coffee before I wrote that.

 

For the Regional series there were 9 events last year.
Usually only four runs per event.
http://www.soloontario.com/solo2/

There is another series that is more for the fun of it. This year they have 6 events on the schedule. Plus 2 or 3 pro solos.
Usually five runs per event.
http://www.wiredmotorsports.com/pitl/pitl-info.html

Then there are other individual club events and stuff where you get five or six runs probably.

I think I ran 12 events last year all told with four or five runs at each.