anyone with experience of road race rubber being used for autocrossing vs. the autocross rubber?

most articles/comparisons in GRM are for Azenis to Hoosiers but not really hoosier to hoosier.

for a typical 50 second course, any estimates for how much faster the A/X version would be compared to the race rubber?

or do you just get the road race rubber for longevity on autocrossing plus able to use on track? tia.

 

Never been on Hoosier A's. Been running Kumhos for years, and one time I took the roadrace Civic out to the autocross on Hoosier R's and it was verrry slippery. They improved noticeably by the finish once they started heating up.

If I had to guess - As to Rs, probably 2 seconds on a typical course. No real data though. I would rather be on top-tier street tires than R Hoosiers. They just don't heat up enough.

 

For those of us in the south, the R's aren't a bad option at all. Once you get past 90 degrees or so, the A's get awful greasy. A successful combo some of the autoxers use around here is to put R's in front and A's in the back.

The Street TD, or "road" version of the Hoosier bias ply is also a pretty good choice (not comparing radials to bias plys, just rubber). I've used this tire personally for years. I can get a full season out of it, and the grip is only marginally less than the Autocrosser. But again, from June - September (around here) the TD's grip as well as the Autocrossers do.

 

yea..those of us in the sount not only is it a bad option, but some of us keep a set of Roadrace compounds around for those days when its actually faster...

Hoosier A's work at somewhere around 150' throw in a 130' asphalt temp in Perry Ga in June and you can almost hit that sitting on the grid. a couple of runs later and we are borrowing the turbo guys pesticide spray bottles to cool our tires.

What to do?..add $700 to our tire budgets (now we get to have a wet, dry, and "hot" compound....its only $ right?

So the real answer is..sometimes its faster, sometimes its slower...you get a cold day..it might be 3 seconds slower.

One thing the Hoosier does overall though is bring with it the stiffer spring rate with the sidewall, which is worth a bunch in itself. If you are on a budget and picking up roadrace take offs..its not a bad option at all.

Jon K
http://www.seat-time.com

 

From my experience, Hoosier Rs will only work in autocross for heavier cars (my Supra was 3315 lbs and they were pretty decent for the last few runs, we typically get 3 or 4 a day). Still did better on As though.

 

I run the R's in front and the A's in the rear. It gets so hot here that I have to still wet down the fronts to cool them off!

 

Peru ProSolo last year...

Mark Chiles and Jeff Jacobs on A's, Marshall Cone and Ian Baker on R's. Myself and Keith Robertson on A's. Marshall won, Ian in 3rd.

They aren't that bad, and they wear better than A's. Chiles and Jacobs go through a set of fronts PER ProSolo.

 

thanks for all the feedback. i think i'll do the R's as they should not slow me that much and still be used for any lapping or ita days.