[Lara]

Originally Posted by Vicegrip

Welcome to the slippery slope!

I've been TRYING to get my dad down the slippery slope! R comps would be a start. Sway bars, dad!!!

[BillC]

Originally Posted by rbpeirce

Okay. This is a totally new idea to me. I'm assuming you are suggesting stiffer settings, but how does that work? I suspect it would tend to unload the inner wheels a bit but how does that help the outside?

The idea is the upgraded (stiffer) sway bars reduce body roll, which reduces the amount of dynamic camber change that loads up the outer edges of the tires so much. They won't unload the inner wheels any more than your current setup, but you may notice a slight increase in body response going over uneven bumps.

The sway bars aren't a fix for the lack of negative camber, but they are a good compromise for a car that is mostly street-driven.

[rbpeirce]

Originally Posted by Vicegrip

Keep in mind also that 13 track days is a lot longer than many see from set of tires.

Geez! That's something I never thought of. What is typical for street tires? Does anybody know? I was wondering if this kind of wear might just be normal. Maybe it is.

I was only looking at what had happened to the tires and realizing I probably had a bit less mileage on them than I had on the last set. I know I'm pushing harder. For the first time ever I had to replace my brake pads before the end of the season. I also swapped the tires to even the wear, which is probably why the right side shows so much wear. Something I forgot.

[BlackTalon]

If you do not flip them on the wheels than you are not maximizing their life.

Typically 10 track days is the max I could get out of a set before flipping, and then I could get a total of ~20 days. That was in an '80s 911 though; Cayman wear rates may be different.

And of course this all depends on the actual tire used, as there is variation in softness between various tire makes/ models. Hard-as-shit street tires (not summer performance) can last more days then a good summer performance tire. Of course they are not as fun on the track though.

[rbpeirce]

Originally Posted by Vicegrip

Welcome to the slippery slope!

Okay. That's something I've really been trying to avoid. My rule has been don't change the car to go faster. Change it because you've exceeded its capabilities. Many years ago I switched to hi-temp brake fluid. A few years ago I started to use track pads. Now I've been worrying that I might need to add GT3 LCAs, or as suggested yesterday, stiffer sway bars.

If I'm getting what I should out of my tires I don't really have to change anything right now, and if 13 track days is average or better then I just have to live with it.

[rbpeirce]

Originally Posted by Lara

I've been TRYING to get my dad down the slippery slope! R comps would be a start. Sway bars, dad!!!

Please! I'll stick with what I've got as long as it works.

[Chopper Dropper]

Difficult to see the actual wear from your pic. Without changing anything else on the car which sounds like you don't want to do, is flip the tyres on the rims when you start seeing a decent amount of wear on either inside or out which you did not specify, but most likely outer treads worn more.
Dirk

[TomChan]

Like in many forms of sports/hobbies, this is 100% a slippery slope!!! Once a driver advanced their skill to a certain level it is possible to wear the outside of the tires(left front in particular). In extreme cases an advanced level driver can shave off the outside in as little as one weekend. The outside wear is caused by "tire wall compression rollover". I just made that term up for the purpose of explanation. Some cars are more susceptible to TWCR than others, it has to do with the suspension type of the car. The car in question(987) has MacPherson Strut type which is more susceptible than Multi-link type and Double-wishbone type because of how each type "squats" the tire during compression travel.

There's 2 ways to improve outter tire wear:
1) Increase suspension roll stiffness(shocks, springs, sway bars)
2) Increase static negative camber(which "should" be done in conjunction with stiffer suspension parts because you don't want excessive camber gain on top of higher static camber).

There's two ways to manage the wear without making suspension changes:
1) Flip the tire(if non-directional).
2) Corner slower.

I kinda work in tech support... one of the MFAQ is: does perfect wear across the tire always equally to a perfectly setup car? The answer No. To a certain extent loading the outside a little more is usually good thing. It also depends on what the driver's goal is; is the goal to setup the car to peak potential grip or to setup the car to maximize tire wear for x number of days and the driver will just drive to however the car handles? No judgement on these examples. Drivers have different goals.

IMHO and relatively speaking, 13 days out of a set of tires is quite good!! Being an OCD person, in my second year of track driving I freaked out when my tires weren't wearing evenly. That phase passed fast. Now is one set every 2 or 3 days. All relative to pace and what the driver is willing to tolerate.

[rbpeirce]

Originally Posted by rbpeirce

What is typical for street tires?

This is something I actually track. Unfortunately it is difficult to say how much time I spend on track vs. off. Lately it has been pretty much to, from and on but a few years ago I used to do a lot more off-track driving. Anyhow, here is the record:

Michelin PS2 3!
Bridgestone SO4 13
Michelin PSS 18!
Michelin PS4S 13

No idea what was going on with the original tires. Must have been a lot of extraneous road miles. The SO4s were terrible track tires and I probably over-stressed them. I was finally starting to get reasonably quick when I got the PSSs. In fact the best time I ever recorded at Pitt Race was on the third track day I had them. That brings us to the PS4Ss, and 13 days in the context of my past experience doesn't really seem to be that bad.

However, maybe I should go back to the PSSs, good times and good wear. I'm not up on the technology but are they really that different? The PSSs are a couple dollars more expensive and the PS4Ss are newer, but newer isn't always better.

[Vicegrip]

^MuHahahahaha^


One good solid snort of R comp dust and he is one of Us.

Welcome to the world of "tire life is Life"

Yes, here it is all about Heat cycles and lap times.

Spouses, nuclear families, extended families, vacations, life it self all become a calculation of heat cycles to cost.

"lets take the kids to Disney land for the weekend" = WTF?! That is 4 sets of tires!!!

Where the slippery slope slides over the edge. https://www.roadandtrack.com/motorsp...gKxzkkkDte-RBk