DOT R Compound Tire Comparison

Published: December 12, 2016; updated: September 19, 2017

The charts below are primarily compiled from NASA PT classification, Emilio Cervantes' forum posts, my own experience, feedback of other drivers and some guesses. Rain usage is covered here.

Grip Level

The number in parentheses is the tire's treadwear rating, where I could find it. Continental tires are not DOT approved and hence have no treadwear rating.

Tires ordered by grip level, highest to lowest:

Wear

Tires ordered by wear rate, slowest to fastest:

Notes

Grip level is based on the car running 9/10ths to 10/10ths in appropriate conditions, meaning at most 4-5 laps for autocross compounds (Hoosier A7, Hoosier A6, BFGoodrich g-Force R1 S, Goodyear Eagle RS AC) and 20-30 minutes for the other tires.

Grip level is indicated for brand new or low heat cycle count tires. Different tires lose grip at different rates over the heat cycles; old tires will be ordered differently.

Available sizes vary from tire to tire. A tire that has a lower indicated grip level but a wider available size may outperform a tire with a higher indicated grip level but narrower available sizes.

Wear rate is based on the car running 20-30 minute HPDE sessions/sprint races. Autocross compound tires will heat cycle out long before their tread wears out when used for 4-5 laps at a time.

Hoosier A6 with a large number of heat cycles on them have very similar grip to Hoosier R6 with a similar number of heat cycles, and seem to have similar wear rates. In particular, A6 do not grease up and drop off after 5 laps in this condition. I have no personal experience running brand new A6s or A7s, so can't comment on that. It seems that getting scrub A6s is basically no worse than getting scrub R6s.

Take-off Hoosier SM6 and Hoosier SM7 tend to have SM-specific shoulder wear on the outer ~1" of the tire tread. This typically causes the tire to cord in that area first no matter if it is mounted with that spot inside or outside. As a result, useful life of take-off SM6 and SM7 is often significantly less than one would expect just looking at tread - easily half of that. The shoulder wear is a result of SCCA SM cars not having enough front camber; NASA allows extended lower ball joints which permit more camber and as a result Toyo RR take-offs are often immune to this wear issue.

Hoosier compounds start off with a higher level of grip than Toyo/Maxxis/Nitto compounds, however Hoosier tires lose their grip faster than Toyo/Maxxis/Nitto ones. Around the middle of their tread life, which is where most of HPDE/non-competitive driving happens, Toyo RR and Maxxis RC-1 match or outperform Hoosier tires.

Once heat cycled out, Toyo RR, Hoosier R6/SM6/SM7 and Continental EC-DR tires have very similar grip levels. Of those, Toyo RR seem to last quite a bit longer than the others.

I found Hankook C30/C50/C70 and to a lesser degree Maxxis RC-1 to lock up easily under braking, as opposed to Nitto NT-01 and Toyo RR/R888/RA-1. Cars without ABS may prefer Nitto and Toyo tires.

When driven at 7/10ths to 8/10ths, unshaved Toyo RA-1 will produce similar performance and wear rate to shaved (to 4/32" or less) RA-1s. At 9/10ths to 10/10ths the unshaved tires are slower and wear out quicker.

Nitto NT-01, Toyo R888 and Toyo RA-1 in my experience have very similar compounds in terms of grip level. Some say the three in fact use the same compound. While NT-01 does seem to last longer than the other two, RA-1 does not seem to last much longer than R888, nor does RA-1 seem to have a flat grip curve over time like it reportedly did back in the day.

While Nitto NT-01 at one point was the go-to HPDE/non-competitive track day tire, today Toyo RR offers superior grip as well as better longevity.

Maxxis RC-1 is between Nitto NT-01 and Toyo RR in grip level and if it wears evenly will outlast RR. However, I have had shoulder wear on various sizes of RC-1s, both inside and outside, which persisted despite raising pressures. RC-1s are also prone to locking up under hard braking in my experience. I threw out most of the RC-1s with half of the tread remaining in the middle but with tires either corded on the shoulders or flatspotted. If you can wear them evenly, RC-1 may well be the best bang for the buck for non-competitive use.

Continental EC-DR tires are using a harder compound than Hoosier R6. Internet wisdom says EC-DR are using an older compound, R3S03 or R3S04. Others say EC-DR and R6 are identical tires.

References