Got a track related question? I'll try to answer.

[EAGLE5]

Originally Posted by strat61caster

Not to pile on here but what responses were you expecting here?

You are so much nicer than me.

[strat61caster]

Originally Posted by jsimon7777

You are so much nicer than me.

Nah, we both have good moods and bad ones. I've seen you post a well worded paragraph that I would call 'pearls before swine' and I've pissed off my fair share of people.

[86league]

First HPDE track weekend with the BRZ at MSR Houston. Rain/wet track for half the sessions both days so I got about 4 dry sessions (~20 min each).

Had the car about 2 months, and it's stock except for camber bolts, pads/fluid - I'm still getting comfortable with the car, and I have tons still to learn - so I wasn't driving it very hard yet - but I have a some tire questions...

1) will 1 weekend of (mild) heat cycling make the stock tires wet traction degrade severely?
2) does this little bit of wear on the outside shoulder indicate I need more camber - or have they not been worked hard enough to tell?

Additional info :

Stock tires with 18500 road miles on them before the weekend (purchased with 18,000 miles 2 months ago). Started at 34 psi cold. Hot pressures were bled down to 37 and then 36 after a recommendation of my instructor to try letting a pound out...

At the track, I thought I was working them across the whole tire - had what looked like flowing rubber across the whole width, but after the 45 mile drive home the above pics make it look like that was probably just pickup from the track. (?) The outside shoulder looks to be only very slightly torn up...
Front (driver side):

Rear (drivers side) :


I have the Subaru crash bolts at about -1.5 camber and near 0 toe.

Wet traction : Saturday they seemed OK - not great wet grip, but I could manage - The last session Sunday they felt like I was driving on snow - by far the least traction of any tire I've ever driven in the wet (30 years driving). Will heat cycling these tires make them harder and make the wet grip very poor?

My instructor suggested that if there was a chance of rain for my next track event I should perhaps think twice about bringing these tires back.

I was hoping I could run these for a couple more weekends and "use them up" before going to a more track focused tire - don't care if I gave up ultimate time - I'm still very much learning how to drive, I don't need to drive fast. What would be good tire options for durability/good learning tire for track and to/from track - not ultimate lap times?

Best lap of the weekend - looking at this after the fact it's painfully obvious how much I need to improve - but this might help show how "hard" I was driving the tires before they got super slick in the rain.

[ame="https://www.youtube.com/watch?v=tW9AofYr3NY"]HMSR 2016 09 26 S2 L2 - YouTube[/ame]

Thanks for the thoughts...

[Pat]

More camber would help. I don't know if you NEED more. I guess that depends on your priorities. But I run about 3.2* of camber up front on stock suspension and think that's in the right neighborhood for even tire wear and maximum grip on r-comps. For those tires you could get away with less than that, but think you'd benefit from more than what you have.

[CSG Mike]

You're not going to significantly increase wet grip unless you get dedicated wet tires; I say keep using them until you finish em off.

[Kuri]

Originally Posted by 86league

First HPDE track weekend with the BRZ at MSR Houston. Rain/wet track for half the sessions both days so I got about 4 dry sessions (~20 min each).

Had the car about 2 months, and it's stock except for camber bolts, pads/fluid - I'm still getting comfortable with the car, and I have tons still to learn - so I wasn't driving it very hard yet - but I have a some tire questions...

1) will 1 weekend of (mild) heat cycling make the stock tires wet traction degrade severely?
2) does this little bit of wear on the outside shoulder indicate I need more camber - or have they not been worked hard enough to tell?

Additional info :

Stock tires with 18500 road miles on them before the weekend (purchased with 18,000 miles 2 months ago). Started at 34 psi cold. Hot pressures were bled down to 37 and then 36 after a recommendation of my instructor to try letting a pound out...

At the track, I thought I was working them across the whole tire - had what looked like flowing rubber across the whole width, but after the 45 mile drive home the above pics make it look like that was probably just pickup from the track. (?) The outside shoulder looks to be only very slightly torn up...
Front (driver side):

Rear (drivers side) :


I have the Subaru crash bolts at about -1.5 camber and near 0 toe.

Wet traction : Saturday they seemed OK - not great wet grip, but I could manage - The last session Sunday they felt like I was driving on snow - by far the least traction of any tire I've ever driven in the wet (30 years driving). Will heat cycling these tires make them harder and make the wet grip very poor?

My instructor suggested that if there was a chance of rain for my next track event I should perhaps think twice about bringing these tires back.

I was hoping I could run these for a couple more weekends and "use them up" before going to a more track focused tire - don't care if I gave up ultimate time - I'm still very much learning how to drive, I don't need to drive fast. What would be good tire options for durability/good learning tire for track and to/from track - not ultimate lap times?

Best lap of the weekend - looking at this after the fact it's painfully obvious how much I need to improve - but this might help show how "hard" I was driving the tires before they got super slick in the rain.

Thanks for the thoughts...

Sup. I was #286. White/Black BRZ that parked in your area

I recommend a bit more camber

[OkieSnuffBox]

Originally Posted by CSG Mike

You're not going to significantly increase wet grip unless you get dedicated wet tires; I say keep using them until you finish em off.

This. Even something like an R1R was pretty dicey when it was really wet at my last track weekend.

I nearly embarrased myself on the out lap (under yellow) and had to walk the car all the way out to the curb.

You'll also find on a well worn track the "wet line" will be different than the "dry line" so you can find some rougher asphalt with more grip.

[Lynxis]

Originally Posted by 86league

First HPDE track weekend with the BRZ at MSR Houston. Rain/wet track for half the sessions both days so I got about 4 dry sessions (~20 min each).

Had the car about 2 months, and it's stock except for camber bolts, pads/fluid - I'm still getting comfortable with the car, and I have tons still to learn - so I wasn't driving it very hard yet - but I have a some tire questions...

1) will 1 weekend of (mild) heat cycling make the stock tires wet traction degrade severely?
2) does this little bit of wear on the outside shoulder indicate I need more camber - or have they not been worked hard enough to tell?

Additional info :

Stock tires with 18500 road miles on them before the weekend (purchased with 18,000 miles 2 months ago). Started at 34 psi cold. Hot pressures were bled down to 37 and then 36 after a recommendation of my instructor to try letting a pound out...

At the track, I thought I was working them across the whole tire - had what looked like flowing rubber across the whole width, but after the 45 mile drive home the above pics make it look like that was probably just pickup from the track. (?) The outside shoulder looks to be only very slightly torn up...
Front (driver side):

Rear (drivers side) :


I have the Subaru crash bolts at about -1.5 camber and near 0 toe.

Wet traction : Saturday they seemed OK - not great wet grip, but I could manage - The last session Sunday they felt like I was driving on snow - by far the least traction of any tire I've ever driven in the wet (30 years driving). Will heat cycling these tires make them harder and make the wet grip very poor?

My instructor suggested that if there was a chance of rain for my next track event I should perhaps think twice about bringing these tires back.

I was hoping I could run these for a couple more weekends and "use them up" before going to a more track focused tire - don't care if I gave up ultimate time - I'm still very much learning how to drive, I don't need to drive fast. What would be good tire options for durability/good learning tire for track and to/from track - not ultimate lap times?

Best lap of the weekend - looking at this after the fact it's painfully obvious how much I need to improve - but this might help show how "hard" I was driving the tires before they got super slick in the rain.

Thanks for the thoughts...

Get more camber if you can but I'll also note that the soft sidewalls on the OEM tires mean they roll over a fair amount especially at lower pressures and running them hard causes severe shoulder wear.

I would swap your fronts to your rears right away while they're still usable. Another event like this and you will chunk away the whole side of your tire. Ask me how I know, picture for reference:



They looked like yours after 1 autocross event then looked like this after the next.

While you will probably have more ultimate grip with lower pressures, I suggest running the OEM tires at around 40 PSI hot which should help reduce tire rollover and improve shoulder wear. My fronts had no noticeable shoulder wear while I was running them at ~35psi cold but when I started playing with pressures, I ended up running them at 34psi hot and after 2 autocross events like that, both of my front tires looked like that.

[86league]

Originally Posted by Pat

More camber would help. I don't know if you NEED more. I guess that depends on your priorities. But I run about 3.2* of camber up front on stock suspension and think that's in the right neighborhood for even tire wear and maximum grip on r-comps. For those tires you could get away with less than that, but think you'd benefit from more than what you have.

I figured I would need camber more with track tires, thought I'd see if I could get away with simple crash bolts up front for the stock tires before going with more hardware (= $$$)...

Originally Posted by CSG Mike

You're not going to significantly increase wet grip unless you get dedicated wet tires; I say keep using them until you finish em off.

So the apparent change from Sat to Sun in the amount of wet grip is more likely just conditions or lack of driver skill vs. the tires changing due to heat cycling?

Originally Posted by Kuri

Sup. I was #286. White/Black BRZ that parked in your area

I recommend a bit more camber

Hey. Nice car - looked like you had quite a few go-fast goodies

More camber front and rear? The front I think I can do easily with SPL lower "crash" bolts - but the rear is going to require LCA's, right? Assume I'll need to do that at some point ... as well as perhaps camber plates in front...

Originally Posted by OkieSnuffBox

You'll also find on a well worn track the "wet line" will be different than the "dry line" so you can find some rougher asphalt with more grip.

I was trying feel out the dry line vs off(rain) line but it just seemed to be way slicker everywhere Sunday vs. Saturday. The only thing I knew that was different was 2(.5?) additional heat cycles in the tires (Sun morning and mostly dry last session Sat) before it rained on Sunday.

Originally Posted by Lynxis

Get more camber if you can but I'll also note that the soft sidewalls on the OEM tires mean they roll over a fair amount especially at lower pressures and running them hard causes severe shoulder wear.

I would swap your fronts to your rears right away while they're still usable. Another event like this and you will chunk away the whole side of your tire.

Thanks for the info - I planned to swap F/R before the next track event. The "scuff" line wasn't all that far down around the sidewall vs. what I saw on pilot super sports on my previous car, so I didn't think I was rolling them too much, but I may be getting that outer shoulder hotter than I think. I bought an IR temp probe for next time -- I know a real tire pyro would be better... I'll bias my pressures higher next time and see what happens.

[CSG Mike]

Correct, wet is wet. Changing tires will not significantly change grip, without making a lot of non-wet compromises.

[strat61caster]

The average driver vastly overestimates how much traction is available in the wet, regardless of tire or setup choice. The learning curve is very quick the first few track days if you're into it, there's likely a big difference from how you drove in the first session to how you drove in the last session, I'd gamble the tires didn't lose grip, you got more comfortable at their limit, unless you've got data to show you were slower later.

Use up those Primacys, saves $$$ and is still fun and educational with the right attitude.

[86league]

Originally Posted by CSG Mike

Correct, wet is wet. Changing tires will not significantly change grip, without making a lot of non-wet compromises.

Originally Posted by strat61caster

<snip> I'd gamble the tires didn't lose grip, you got more comfortable at their limit, unless you've got data to show you were slower later.

Use up those Primacys, saves $$$ and is still fun and educational with the right attitude.

Thanks Mike/Strat... Fair enough - I'll just assume/admit the nut behind the wheel was loose and still needs tightening...

One other questions that occurs to me on tires :

1) Would a 245/40-17 tire on a 9" wheel last longer than a 225/45-17 on an 8" wheel (same type/compound for both)? Just curious if the extra width is "worked" less and would last longer...
2) From what I read here, the 245s are likely be slower overall due to additional rolling resistance and drag - but what would they do for cornering feel, grip, speeds?

Thanks all!

Jim

[strat61caster]

Originally Posted by 86league

One other questions that occurs to me on tires

How often do you plan on hitting the track and will the tire see DD miles?

Odds are you'll only track a few times per year and use the tire up on the street, my 2 cents is go for the cheaper tire in a 215 on OE wheels and spend the money on seat time and alignment upgrades.

Hankook RS3's in OE size are ~$115 each right now and if you want to save them for track use a set of used OE wheels is typically $400 or less.

http://www.ft86club.com/forums/showthread.php?t=111065

http://www.tirerack.com/tires/tires....22V2&tab=Sizes

Ultimately do what makes you happy.

[CSG Mike]

Originally Posted by 86league

Thanks Mike/Strat... Fair enough - I'll just assume/admit the nut behind the wheel was loose and still needs tightening...

One other questions that occurs to me on tires :

1) Would a 245/40-17 tire on a 9" wheel last longer than a 225/45-17 on an 8" wheel (same type/compound for both)? Just curious if the extra width is "worked" less and would last longer...
2) From what I read here, the 245s are likely be slower overall due to additional rolling resistance and drag - but what would they do for cornering feel, grip, speeds?

Thanks all!

Jim

The wider tire will likely last longer because the load is spread over more tire.

I do recommend a quality wheel; avoid the cheap knockoff brands. Feel free to PM for some wheel options; let me know yuor budget up front!