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

[7thgear]

Originally Posted by CSG Mike

If you have to reduce steering input to get around the corner, it's faster. If you're countersteering, it's slower. Not reducing steering input enough MAY result in eventual countersteering, so you have to find the fine balance.

fucking huge lightbulb just went off, thank you so much Mike!




as for the slip angle + torsen delay, to "trust" it is to just practice until muscle memory does its thing??

[Pat]

Originally Posted by TrogDor the Burninator

This may be a silly question, but in my last NASA track event at Heartland Park Topeka I became curious of the optimum RPM to shift at when traversing the long straight.

Typically I find myself shifting around 7200. (Car is NA with only catback exhaust)

At what point does the maxing out of a lower gear actually take speed away from you if you would have shifted instead? Is it best to ride a gear to the redline or shift sooner?

Whatever you were shifting at must have been wrong. Did you see the white BRZ there? Man, that guy was FAST.

[CSG Mike]

Originally Posted by 7thgear

fucking huge lightbulb just went off, thank you so much Mike!




as for the slip angle + torsen delay, to "trust" it is to just practice until muscle memory does its thing??

You just have to learn the conditions under which it'll "activate". It varies by the setup and by car.

[kavanagh]

So Mike, having the Torsen is another good 'learning aide'? I'm thinking of going back to my stock tires next time out instead of the PSS just to get practice in the slip angle.


Sent from a secret volcano base using trained sharks

[CSG Mike]

Originally Posted by kavanagh

So Mike, having the Torsen is another good 'learning aide'? I'm thinking of going back to my stock tires next time out instead of the PSS just to get practice in the slip angle.


Sent from a secret volcano base using trained sharks

A rather unforgiving one, but yes. A Clutch type is superior in every way for hard driving, but can be less daily driver friendly if set up incorrectly.

[ZionsWrath]

I am going to a 2 day event in less than a week. I have 1 day on stock tires and after this event I am considering replacing them. But I have a small dilemma in doing so. Should I buy a new set of wheels for them? Should I swap them when I get to track and put street set on when I leave?

Either way I am leaning towards a dedicated set that can in the future fit AP Sprint kit. So for wheels I am looking at Kosei K4R 17x8 +36 or XXR 17x8.25 +35

I am leaning to the XXR because they are cheap and can put a 245 in the future if needed.

Next item is tire itself, if I get a track dedicated set what should I have? If I drive it to and from the track a couple hundred miles what should I have? Which is better option?

Closest track to me is ~150 miles.

[dradernh]

Originally Posted by ZionsWrath

I am going to a 2 day event in less than a week. I have 1 day on stock tires and after this event I am considering replacing them. But I have a small dilemma in doing so. Should I buy a new set of wheels for them? Should I swap them when I get to track and put street set on when I leave?

Either way I am leaning towards a dedicated set that can in the future fit AP Sprint kit. So for wheels I am looking at Kosei K4R 17x8 +36 or XXR 17x8.25 +35

I am leaning to the XXR because they are cheap and can put a 245 in the future if needed.

Next item is tire itself, if I get a track dedicated set what should I have? If I drive it to and from the track a couple hundred miles what should I have? Which is better option?

Closest track to me is ~150 miles.

It sounds like you're going to end up with a dedicated set of track wheels and tires, and you'll drive to the events on another set of wheels and tires. The rule of thumb with tires is that the tread width be +/- 1" of the wheel width; within that 2" distance, a narrower tire will generally provide you with more responsive handling. If it were me, I'd be looking at 225 tires for either of those wheels - compared to a 245, they'd give you a triple: cheaper, lighter, and a better match of tire/wheel widths.

If you need a 245-width tire due to how much power you have, you might want to consider moving to a 9" wheel. For reference, on a 318 RWHP car weighing 2893# on track, I run 235 DOT-Rs on a 9" wheel. I could run 245s, but they're hardly wider than the 235s and the 235 is already plenty wide for that wheel. And I could, and have, run 255s, but with the DOT-R BFG R1s I run I would need a wider wheel to take full advantage of the 255's tread width.

Once you put the sprint kit on the car, you might consider a DOT-R compound tire. (Mind you, I'm not sure how much experience you have. IIRC, it's just a little?) Assuming you do eventually look at a DOT-R, you could do worse than start with a Nitto NT01. With an 8" wheel, I'd go with the 225, and with a 9" wheel, the 235, or the 245 if you need it.

[ZionsWrath]

Originally Posted by dradernh

It sounds like you're going to end up with a dedicated set of track wheels and tires, and you'll drive to the events on another set of wheels and tires. The rule of thumb with tires is that the tread width be +/- 1" of the wheel width; within that 2" distance, a narrower tire will generally provide you with more responsive handling. If it were me, I'd be looking at 225 tires for either of those wheels - compared to a 245, they'd give you a triple: cheaper, lighter, and a better match of tire/wheel widths.

If you need a 245-width tire due to how much power you have, you might want to consider moving to a 9" wheel.

Once you put the sprint kit on the car, you might consider a DOT-R compound tire. (Mind you, I'm not sure how much experience you have. IIRC, it's just a little.) Assuming you do eventually look at a DOT-R, you could do worse than start with a Nitto NT01.

Yes I don't have any experience, just 1 day. I am just thinking to "future proof" myself with the wheel purchase if I can. I was planning a 225 tire as you mention. The ability to run a wider tire is if I decide to add power in the future. Reason I didn't really want a 9" is because then I have to add in coilovers to fit with camber and not really wanting to fall too deep in the rabbit hole you know? Have a lot of driving to do before that though...

[dradernh]

Originally Posted by ZionsWrath

Yes I don't have any experience, just 1 day. I am just thinking to "future proof" myself with the wheel purchase if I can. I was planning a 225 tire as you mention. The ability to run a wider tire is if I decide to add power in the future. Reason I didn't really want a 9" is because then I have to add in coilovers to fit with camber and not really wanting to fall too deep in the rabbit hole you know? Have a lot of driving to do before that though...

Well, you can do a lot on a 225; based on my experience, I'd just be careful of over-tiring the car. It's not necessary. For example, a guy in my TT club in a 200 RWHP street car with modest coilovers runs the Glen in 2:14 on 225s.

[jvincent]

@ZionsWrath, I'm pretty much in the same situation as you, and after a lot of research on here, I'm going with 225/40/18 when I burn out my stock tires.

My car is my DD, and I will probably do 3 -4 track days a season. I have one full day under my belt this year, and I figure my best lap was about 2:55.

The fast guys at that track do around 2:30 in the FRS so while there's room for improvement, I figure I'll get faster with seat time long before the equipment becomes a limiting factor so there's no point in going crazy with performance mods.

[7thgear]

Originally Posted by ZionsWrath

Yes I don't have any experience, just 1 day. I am just thinking to "future proof" myself with the wheel purchase if I can. I was planning a 225 tire as you mention. The ability to run a wider tire is if I decide to add power in the future. Reason I didn't really want a 9" is because then I have to add in coilovers to fit with camber and not really wanting to fall too deep in the rabbit hole you know? Have a lot of driving to do before that though...

if you truly want to future proof then get a lightweight 17 x 9 wheel.


this will allow you to run tires from 225 to 245/255 to match your power levels if you start modding the engine


17x9 is also the max size for the STX class, so if you ever decide to play in autocross you've got at least one thing optimized.

[dp1]

Originally Posted by ZionsWrath

Yes I don't have any experience, just 1 day. I am just thinking to "future proof" myself with the wheel purchase if I can. I was planning a 225 tire as you mention. The ability to run a wider tire is if I decide to add power in the future. Reason I didn't really want a 9" is because then I have to add in coilovers to fit with camber and not really wanting to fall too deep in the rabbit hole you know? Have a lot of driving to do before that though...

I run 17x8 with 225/45-17 MPSS on street and 235/40-17 Toyo RA1 on track (4yrs HPDE only experience), with JR SC, Ohlins and many other mods. If I change anything, it will be to go down to 225/45-17 for track with RS-3s (cheaper and more than good enough to play with).

[ZionsWrath]

Originally Posted by 7thgear

if you truly want to future proof then get a lightweight 17 x 9 wheel.


this will allow you to run tires from 225 to 245/255 to match your power levels if you start modding the engine


17x9 is also the max size for the STX class, so if you ever decide to play in autocross you've got at least one thing optimized.

Will 9" fit stock? I have -1.3 camber (may look at Raceseng camber plate in future for more with bilsteins/springs), will a 9" with 245 rub?

[jvincent]

You'll probably have to run a pretty low offset to run 9" up front if you want to stay flush or less.

Check the wheel fitment thread for the offsets that end up being flush.