Autocross, time attack, track day tips, set up tricks - what worked for you?

[Burnsy895]

Hey Guys,


I come from a motorcycle background and have started modifying my Fiesta ST to do some Canadian Time Attack stuff. I cannot leave well enough alone and have to modify/compete with everything.

I have started to shed the car of some extra weight (picture a weak B-Pillar Back weight reduction (seats, trunk trim etc)


I installed HSD Coilovers (I purchased new but I believe they were ordered with custom springs because the stickers on the spring were 7K which wasn't a website option when doing research). I have also installed Hawk Street/Race pads in the front and Hawk 5.0 pads in the rear with slotted stoptech rotors with stainless lines and race brake fluid. I have cobb sway bars front and rear. have adjustable camber bolts in the rear as well to help with dialing in the alignment.

Power wise I am about stage 3 with a stratified custom tune

The event I plan to be running has the pirelli trofeo R DOT tires as the spec tyre which leaves me some strange tire options. I am leaning towards the 225/50R16 vs the 205/55R16 for sizing unless I can be told otherwise. (the wheels I have are 16x6.5 for width.


Just wondering if there were any settings you found to work better than others as far as alignment set up etc. I am not looking for you to give away secrets but a step in the right direction will definitely help.

Any positive info would be appreciated!


Cheers

 

[alexrex20]

I don't think any of those tire sizes will fit without serious clearance issues. Looking at their website, your best bet would be 205/45-17 on stock wheels. None of the 16s will fit. As for track alignment, I like -2.5 camber up front and as much negative camber as you can get in the rear. if you're getting serious, i would get some camber plates/shims for the rear hubs. zero or just a hair of toe-out for the rear and .1deg toe-out up front. 34psi hot all around is a good starting point, then adjust for rotation.

 

[green_henry]

I don't think any of those tire sizes will fit without serious clearance issues. Looking at their website, your best bet would be 205/45-17 on stock wheels. None of the 16s will fit. As for track alignment, I like -2.5 camber up front and as much negative camber as you can get in the rear. if you're getting serious, i would get some camber plates/shims for the rear hubs. zero or just a hair of toe-out for the rear and .1deg toe-out up front. 34psi hot all around is a good starting point, then adjust for rotation.

34 psi seems a bit low to me, but I haven't experimented with tire pressure very much. Did you originally run them higher? Did lowering the pressure "fix" a specific problem?

 

[alexrex20]

34 psi seems a bit low to me, but I haven't experimented with tire pressure very much. Did you originally run them higher? Did lowering the pressure "fix" a specific problem?

It fixed the problem of no grip.

My first track day in the FiST I started at 32/32 cold. Fuck that 39/36 door sticker nonsense. After a session, pressure was up to something like 38/36 and temps were noticeably higher at the center of the tread. It felt on top of the track so I gradually went down on pressure. At that point I'm pretty unscientific. I just use my handheld FLIR to read the hot spots on the tire then bleed out some air from the tire without a gauge. I just burp the valve stem for a second. The next morning, cold pressure was 28/27. For my area, I'd recommend 32/32 HOT but climate plays a small role in ideal air pressure so I went with 34/34 HOT for people that might live in colder regions (which is just about everywhere, honestly).

You'll know real quick (on the track) if your tires have too much pressure.

Every car is different and alignment plays a significant role in ideal tire pressure. The whole goal is an even contact patch.

 

[green_henry]

It fixed the problem of no grip.

My first track day in the FiST I started at 32/32 cold. Fuck that 39/36 door sticker nonsense. After a session, pressure was up to something like 38/36 and temps were noticeably higher at the center of the tread. It felt on top of the track so I gradually went down on pressure. At that point I'm pretty unscientific. I just use my handheld FLIR to read the hot spots on the tire then bleed out some air from the tire without a gauge. I just burp the valve stem for a second. The next morning, cold pressure was 28/27. For my area, I'd recommend 32/32 HOT but climate plays a small role in ideal air pressure so I went with 34/34 HOT for people that might live in colder regions (which is just about everywhere, honestly).

You'll know real quick (on the track) if your tires have too much pressure.

Every car is different and alignment plays a significant role in ideal tire pressure. The whole goal is an even contact patch.

Interesting. Last season, I was running 40/40 hot, and it seemed fine. Treadwear was even. Grip was not an issue, but lack of boost was (I haven't upgraded the intercooler yet). Now that I have portable compressor, I'm more comfortable experimenting with different pressures, so I'll try running it lower next time.

 

[Burnsy895]

I don't think any of those tire sizes will fit without serious clearance issues. Looking at their website, your best bet would be 205/45-17 on stock wheels. None of the 16s will fit. As for track alignment, I like -2.5 camber up front and as much negative camber as you can get in the rear. if you're getting serious, i would get some camber plates/shims for the rear hubs. zero or just a hair of toe-out for the rear and .1deg toe-out up front. 34psi hot all around is a good starting point, then adjust for rotation.

Thanks!

The camber will be a good start I'm sure. I know it's all about your own driving styles and such but a point in the right direction will be a big help.

The tire pressure sounds about right from what I can tell and I know the Pirelli Website has some guidelines to base it off of and how to get it hot. Bikes are easier because they have tire warmers and you know the temp that is coming off the warmers, cars are a pain having to bring them up carefully

Sent from my Pixel 2 XL using Tapatalk

 

[Brib]

I don't think any of those tire sizes will fit without serious clearance issues. Looking at their website, your best bet would be 205/45-17 on stock wheels. None of the 16s will fit. As for track alignment, I like -2.5 camber up front and as much negative camber as you can get in the rear. if you're getting serious, i would get some camber plates/shims for the rear hubs. zero or just a hair of toe-out for the rear and .1deg toe-out up front. 34psi hot all around is a good starting point, then adjust for rotation.

Alex, any experience with shimming the rear? Everything I have read says that it screws up the rear ABS sensor reading without modifying the sensor bracket. My car has -2.5 front currently (camber bolts, koni yellow, swift springs) but no changes to rear.

 

[maestromaestro]

I don't think any of those tire sizes will fit without serious clearance issues. Looking at their website, your best bet would be 205/45-17 on stock wheels. None of the 16s will fit. As for track alignment, I like -2.5 camber up front and as much negative camber as you can get in the rear. if you're getting serious, i would get some camber plates/shims for the rear hubs. zero or just a hair of toe-out for the rear and .1deg toe-out up front. 34psi hot all around is a good starting point, then adjust for rotation.

I have 225/45-16s that fit no problems in the rear, but because I have to use 8mm spacers in the front to clear the WW BBK, I had to roll the fenders ( not that there’s much to roll) and to clip the brackets for bolting the front clip to the fender - otherwise I had the sidewalls being cut into spaghetti. 215/45-16 fit without a problem.

I should add that the wheels are 16x7.

 

[Plainrt]

Different makes of tires will vary in tire pressure. So for the people throwing that data out there it would be great to put the tire make in there. Also you will find that lower psi on low grip surfaces will work better vs higher grip concrete etc. I’d try to find a 225/45/16 and adjust ride height to work. With correct offset it shouldn’t be a problem.

 

[maestromaestro]

Different makes of tires will vary in tire pressure. So for the people throwing that data out there it would be great to put the tire make in there. Also you will find that lower psi on low grip surfaces will work better vs higher grip concrete etc. I’d try to find a 225/45/16 and adjust ride height to work. With correct offset it shouldn’t be a problem.

Ultimately, one has to figure out what the proper pressure is by observing the wear/rubbing out of witness marks or, better yet, by measuring the temperature across the width of all 4. So, no "recommendation" is possible for all conditions or all tires.

Obviously, if the track is wet, you don't want low pressure. If you're climbing rocks, you do.

 

[Plainrt]

Ultimately, one has to figure out what the proper pressure is by observing the wear/rubbing out of witness marks or, better yet, by measuring the temperature across the width of all 4. So, no "recommendation" is possible for all conditions or all tires.

Talking starting points....... not actual dialed in psi.

 

[maestromaestro]

Talking starting points....... not actual dialed in psi.

Given that those are also dependent on the road, ambient temperature, tire, and driving style - you can start at any value (within reason).

 

[Plainrt]

Yeah ok your clearly the expert.

 

[FiestaAlex]

All I will say is there's no way i'd run LOWER tire pressure voluntarily, or air down to *some point* without using a gauge.

Always run as high as you possibly can on that tire. Less sidewall flex means better handling and less rolling resistance. Less heat. Better protection for rim as well.

Airing down is for offroad, snow and drag racing, not track.

 

[Plainrt]

All I will say is there's no way i'd run LOWER tire pressure voluntarily, or air down to *some point* without using a gauge.

Always run as high as you possibly can on that tire. Less sidewall flex means better handling and less rolling resistance. Less heat. Better protection for rim as well.

Airing down is for offroad, snow and drag racing, not track.

People need to learn how to read. No one said to just randomly dump psi down to whatever........ I was talking a few psi difference on different surface. And no the highest psi isn’t the best for grip and tire wear either. I guess I’m new to track stuff and autocross lol.

 

[maestromaestro]

All I will say is there's no way i'd run LOWER tire pressure voluntarily, or air down to *some point* without using a gauge.

Always run as high as you possibly can on that tire. Less sidewall flex means better handling and less rolling resistance. Less heat. Better protection for rim as well.

Airing down is for offroad, snow and drag racing, not track.

Wrong - and a bad advice.

Tire pressure needs to be such that you have the biggest contact patch without excessive roll. If the track is wet, you need higher pressure to channel the water, but not on the dry track.

Pressure gauge is good to check the values, but these numbers are meaningless unless you a) measure temperature across the tire width and b) actually look at the rubber to see how much roll after you pit. Either use chalk or those upward triangles on the sidewall that most tires have.