Piston Slap: Going Brazillian on Bridgestones

Sajeev Mehta
by Sajeev Mehta
piston slap going brazillian on bridgestones

TTAC reader Mockard writes:

As a web-savvy car enthusiast and budget autocrosser, I try to do a lot of reading before pulling the trigger on a big purchase. With a set of R-compounds now hitting the $800 mark, I want to make the most of my investment. The consensus seems to be that shaving tires can make them perform better and last longer, but I remain skeptical… The cynic in me suspects that shaving is just a way to reduce tire life and pad the shaver’s wallet to the tune of $10 a tire. Why couldn’t tire manufacturers just build tires “shaved” from the beginning, if there was a real advantage?

Sajeev responds:

Judging by the clearance pricing I (occasionally) see for certain sizes of specialty tires on Tirerack.com, I suspect that multiple tread depths of the same model is like selling the Toyota Venza with the Highlander and the Lexus RX: it’s a big risk. Economies of scale rule, so let the grassroots racing community take that financial burden, right?

In theory, shaving tires is a good idea: reduces tread squirm, puts a wider footprint on the pavement and minimizes rubber-degrading via overheating. But not all R-compound tires behave the same way on the same car. And some tracks eat more rubber than others: from my limited time in racing, purpose made asphalt tracks are friendlier to rubber than a coned-off concrete parking lot. It depends on what you want, and what you want to spend. Weekend autocrossers honing their driving skills don’t need the competitive “edge” of a shaved tire, and its opportunity cost. A hardcore Spec Miata racer might beg to differ.

But that’s only the opinion of one dude with limited track time. So now I am throwing the ball in your court. It’s time for the B&B to discuss shaved tires.

Join the conversation
2 of 17 comments
  • Power6 Power6 on Mar 13, 2009

    I think it really depends on what you are doing with your car. I know my philosophy seems to be different than other people I encounter at the track. If you are driving to race and win and expense is a lesser consideration, then probably shaved tires are better, you get them to the proper depth for best traction. If you are to this level I trust you are logging your tire temps so you could figure out the best depth over a few sets of tires? If you are just out to challenge yourself and be a better driver, I don't even see the point in R compounds, unless you are looking to get experience with the tricker limits of race rubber. Myself I run Bridgestone RE-01Rs, they run great rain or shine, don't chunk even on the hottest of days on the track, and last a whole season of street and track for me. They have plenty of stick, even when they are on the cooler side which would be useful for auto-x probably. I give up a little I guess by not running street tires, and having track tires, but I don't care if I am a little slower. I value durability over ultimate capability, I like showing up and practicing my skills, not worrying too much about my stuff.

  • Hraefn Hraefn on Mar 16, 2009

    Thanks everyone for the feedback. This season is about a refresher for me, and an introduction to autocross for my co-driver. I wanted to give both of us some experience on R-compounds and also save my street tires. I picked up a set of used Toyo RA-1s; they had been shaved and have only had a few cycles through them, and the price was about the same as one new Hoosier A6.

  • Damon Thomas Adding to the POSITIVES... It's a pretty fun car to mod
  • GregLocock Two adjacent states in Australia have different attitudes to roadworthy inspections. In NSW they are annual. In Victoria they only occur at change of ownership. As you'd expect this leads to many people in Vic keeping their old car.So if the worrywarts are correct Victoria's roads would be full of beaten up cars and so have a high accident rate compared with NSW. Oh well, the stats don't agree.https://www.lhd.com.au/lhd-insights/australian-road-death-statistics/
  • Lorenzo In Massachusetts, they used to require an inspection every 6 months, checking your brake lights, turn signals, horn, and headlight alignment, for two bucks.Now I get an "inspection" every two years in California, and all they check is the smog. MAYBE they notice the tire tread, squeaky brakes, or steering when they drive it into the bay, but all they check is the smog equipment and tailpipe emissions.For all they would know, the headlights, horn, and turn signals might not work, and the car has a "speed wobble" at 45 mph. AFAIK, they don't even check EVs.
  • Not Tire shop mechanic tugging on my wheel after I complained of grinding noise didn’t catch that the ball joint was failing. Subsequently failed to prevent the catastrophic failure of the ball joint and separation of the steering knuckle from the car! I’ve never lived in a state that required annual inspection, but can’t say that having the requirement has any bearing on improving safety given my experience with mechanics…
  • Mike978 Wow 700 days even with the recent car shortages.