HPDE on PS4

[evanescent03]

Originally Posted by nextcar

.... I got 8 track days out of them. They were really toasted at the end though ...

toasted as in no grip or did you wear 'em down to the cords?

[ZDan]

Originally Posted by nextcar

In general, the first thing you give up on a more track oriented tire (other than longevity) is performance in wet/cold conditions...

The more AutoX/TT focused 200tw track-oriented tires with most of their tread depth remaining will have comparable wet grip vs. the best "Max Perf" tires. A052s in particular are phenomenal in the wet! They also don't need to be warmed up much, pretty much good to go down to decently cool ambient temps.
Tire Rack tests of the best Max Perf and Extreme Perf tires:
https://www.tirerack.com/tires/tests...y.jsp?ttid=273
https://www.tirerack.com/tires/tests...y.jsp?ttid=269


What the "Extreme Perf" 200tw tires do give up is some hydroplaning resistance. Especially past half tread depth...

[NoHaveMSG]

Z3's were also good in the wet as long as they weren't worn too far.

[nextcar]

Originally Posted by evanescent03

toasted as in no grip or did you wear 'em down to the cords?

Why not both! Took them down to the wear bars, then took them out for a drift session... past the cords to the point of destruction. Don't think I'll ever do that again, had to deal with cutting the cords off the axles and realized you can really damage your brake lines.

[br33z]

Originally Posted by nextcar

There is quite a bit of subjectivity on what is acceptable for a dual use tire...

In general, the first thing you give up on a more track oriented tire (other than longevity) is performance in wet/cold conditions... not much of a problem for me in Southern California, perhaps a big problem in New England.

Around here I see people using RS4s and SX2s for dual purpose track/daily. I just switched my PS4s for SX2s and I daily the car (but it does not get driven far/often). Lots of choices; all are compromises... I chose the SX2s for price/availability (RS4s are on backorder until April). Never used them before; next track day is in 2 weeks!

I do already have a winter set and a place to store the summers so cold temps are not much of an issue. Obviously you get less rain than I do, but given that I don’t really rely on the car, I can probably just opt not to drive if the weather is a problem - though that would not be ideal...

I know it’s a very subjective thing - I think I’ve never even been in a car with “track tires” though so I just wanted anecdotes I’ve heard a lot of people are on SX2s so I’ll keep that in mind for the future.

[evanescent03]

Originally Posted by nextcar

Why not both! Took them down to the wear bars, then took them out for a drift session... past the cords to the point of destruction. Don't think I'll ever do that again, had to deal with cutting the cords off the axles and realized you can really damage your brake lines.

well that sucks! the SC3s had great grip until just before the cords .. then they'd start to fall apart and i had a chunk come off and whip around pulling some paint off my front fender... oops. then i stabbed myself on one of the steel belts or whatever inside the tire... at least it wasn't a brake line! my camaro tires were staggered 275/305 so i'm excited about being able to rotate around and getting more life!

[kevaughan]

Originally Posted by nextcar

Around here I see people using RS4s and SX2s for dual purpose track/daily. I just switched my PS4s for SX2s and I daily the car (but it does not get driven far/often). Lots of choices; all are compromises... I chose the SX2s for price/availability (RS4s are on backorder until April). Never used them before; next track day is in 2 weeks!

Between the Hankook RS4 and SX2, which one is quieter on the street?

[mr.whiskers]

I am planning to autocross my Premacies this season. I am pretty new to autocross, last summer was my first season. I drove Infiniti M37 on GoodYear Eagle Sport all seasons, very heavy car with a lot of body roll. It was fun but seeing the wear on the outer edges of front tires scared me

Got the '22 BRZ base model couple of month ago, my first performance and rwd car.

From reading this thread I am thinking I should get the crash bolts installed after couple of runs. Also what would you recommend for tire pressures. I am up in Canada so in spring/summer the temperatures will probably be from 70-90F. Do i put more air in the front to keep the outer edges from shredding. And what about the rear?

[strat61caster]

Originally Posted by mr.whiskers

I am planning to autocross my Premacies this season. I am pretty new to autocross, last summer was my first season. I drove Infiniti M37 on GoodYear Eagle Sport all seasons, very heavy car with a lot of body roll. It was fun but seeing the wear on the outer edges of front tires scared me

Got the '22 BRZ base model couple of month ago, my first performance and rwd car.

From reading this thread I am thinking I should get the crash bolts installed after couple of runs. Also what would you recommend for tire pressures. I am up in Canada so in spring/summer the temperatures will probably be from 70-90F. Do i put more air in the front to keep the outer edges from shredding. And what about the rear?

Yes camber bolts are good, no downsides.

Personally set the pressures to what the door card says, modern tires aren't the marshmallow balloons of old, the primacies are summer tires. Mine says 35/35psi cold.

[mr.whiskers]

Originally Posted by strat61caster

Yes camber bolts are good, no downsides.

.

I do have to use ones from Subaru to stay in the stock class, correct?

[strat61caster]

Originally Posted by mr.whiskers

I do have to use ones from Subaru to stay in the stock class, correct?

Correct

[Desertnate]

Originally Posted by strat61caster

Yes camber bolts are good, no downsides.

Personally set the pressures to what the door card says, modern tires aren't the marshmallow balloons of old, the primacies are summer tires. Mine says 35/35psi cold.

I think the weight of the car, suspension balance, and drivetrain have a lot to do with how you set the tire pressures.

On my GTI, since it was FWD and understeared, I had to add about 5 PSI to keep the tires off the sidewalls. On my BMW 435 which is a very heavy car that tended to understeer on it's staggered set up I had to add 15 PSI to keep the summer tires off the sidewalls (still under max PSI for the tire, surprisingly). Even when I moved to 200TW tires on a square set up I was adding around 10PSI. I constantly chalked my tires and kept a log to dial things in and make sure I was adding too much.

For a lightweight RWD car like my 22 BRZ I'm looking forward to not having to play around with the air pressures so much.

EDIT: This is for autocross, not a track day.

[nextcar]

Disclaimer: There are a LOT of people more serious about their track days than I am... and as always opinions differ.

When I was starting out, the two biggest improvements I made were:

1) Hiring an all day instructor

2) Controlling tire pressure.

I started out a naysayer, mocking the people that were constantly adjusting their tire pressure like the cars and coffee meme of the tool in the Mustang blaming his crash on not using a digital tire pressure gauge and his crash being due to tires underinflated by 1.5 lbs...

But then I had an "aha" moment, wondering why I was slower and sliding more as the day went on... only to find that due to heat my tires were massively (like 8 lbs over the door sticker!!!) overinflated. Correcting the pressure and going back out opened my eyes... I had been an idiot.

The next step was to guess at what pressure I should be running, and check as soon as I came off the track. Look for scrubbing on the sidewall and it will help with underinflation, but by the time you see the centers wearing due to overinflation it is too late.

So, how do you tell what tire pressure is best for your car, your driving, track conditions, and tire differences? The answer is a tire pyrometer, a fancy name for a digital thermometer that can measure the tire temperature at the outter, middle, and inner portions of the tread. Ideally you want them to be as even as possible. If the center is hotter, you have too much air. If the outsides are hotter you have too little.

The inflation guides in the manual and door jam are for maximum efficiency, not performance guides.

Bonus hint: If you look for a tire pyrometer, you will find they cost between $150 and $500. Ouch! But what is a pyrometer? It is a thermocouple, and the electronics are measuring the resistance across dissimilar metals.

You can buy a tire thermocouple probe on Amazon for $33. Search for "K-type tire pyrometer". (https://www.amazon.com/gp/product/B0...1?ie=UTF8&th=1) Great, now you have a cheap probe that you can stick into your tire tread... how do you read the temperature??? Many, many digital multimeters can accept K-type thermocouples as inputs. A Klein MM400 (goes on sale for $30) can do this, and also is useful for checking circuits, voltages, etc. One of the better $63 investments in my lap times. If you already have a digital multimeter, check to see if it has a temperature setting. If so, you can probably buy a $5 adapter to accept a k-type probe.

Edit: Additional info - on Amazon you can get a thermocouple digital thermometer that accepts k-type probes for even less than a multi-meter, however for an additional $5-$10 a digital multimeter is a much more useful tool.

[Desertnate]

Originally Posted by nextcar

The next step was to guess at what pressure I should be running, and check as soon as I came off the track. Look for scrubbing on the sidewall and it will help with underinflation, but by the time you see the centers wearing due to overinflation it is too late.

I find chalking my tires helps with seeing how close I'm getting to the sidewalls.

Bonus hint: If you look for a tire pyrometer, you will find they cost between $150 and $500. Ouch! But what is a pyrometer? It is a thermocouple, and the electronics are measuring the resistance across dissimilar metals.

You can buy a tire thermocouple probe on Amazon for $33. Search for "K-type tire pyrometer". (https://www.amazon.com/gp/product/B0...1?ie=UTF8&th=1) Great, now you have a cheap probe that you can stick into your tire tread... how do you read the temperature??? Many, many digital multimeters can accept K-type thermocouples as inputs. A Klein MM400 (goes on sale for $30) can do this, and also is useful for checking circuits, voltages, etc. One of the better $63 investments in my lap times. If you already have a digital multimeter, check to see if it has a temperature setting. If so, you can probably buy a $5 adapter to accept a k-type probe.

Wouldn't something like this work for checking the temp of your tires? Just shoot a beam at multiple points across the contact patch to read how hot they are getting. You can find quite a few which are affordable.
https://www.amazon.com/KIZEN-Infrare...xpY2s9dHJ1ZQ==