Race Tracking Your Supra - Information exchange

Rensuhlo

Well-Known Member
First Name
Chuck
Joined
Nov 12, 2022
Threads
12
Messages
773
Reaction score
1,434
Location
Georgia
Car(s)
NA
Finally in a position to buy some 18 squared wheels now that the advans are sold.

T7/Apex are the two that offer a 18x10 squared setup for stock suspension, right?
Sponsored

 

nibble

Well-Known Member
Joined
May 21, 2020
Threads
47
Messages
1,291
Reaction score
1,186
Location
NJ
Car(s)
BMW, Honda, Toyota
What do you all use to air up at the track?

Iā€™m considering buying a compressor but donā€™t want one that sucks.

Also, any suggestions for starting tire pressure for PS4S on track?
most track has compressors available for everyone to use. would be much faster than portable compressor. otherwise, you could use one came with the car. I usually start high pressure and go lower depends on condition and leave it all weekend long until I come back home. - so would have less things to think about.
 

razorlab

Well-Known Member
First Name
Bryan / Briana
Joined
Oct 2, 2021
Threads
23
Messages
4,804
Reaction score
9,720
Location
Your moms bedsheets
Car(s)
Not a Corvette.
What do you all use to air up at the track?

Iā€™m considering buying a compressor but donā€™t want one that sucks.

Also, any suggestions for starting tire pressure for PS4S on track?
Both Dewalt and Ryobi make great small compressors that are set and forget. Meaning you set a pressure and it auto shuts off when it reaches it. Recommend either. Depends on what ecosystem you have already invested in, if at all.
 

kaj

Well-Known Member
First Name
Jason
Joined
Aug 6, 2022
Threads
35
Messages
2,072
Reaction score
2,408
Location
Fresno, CA
Car(s)
2021 Supra
What do you all use to air up at the track?

Iā€™m considering buying a compressor but donā€™t want one that sucks.

Also, any suggestions for starting tire pressure for PS4S on track?
I use this since all of my hand tools are DeWalt. This runs off the cigarette lighter or a battery. I set the PSI and it runs to that pressure and stops. It even adds as extra 0.2 psi or so to compensate for air loss when you remove it lol

download (2).jpeg


Relevant video with respect to set up and oversteer/understeer being down to driver preference:

It's true even at the highest levels of motorsport. Both can be fast.

My limited understanding is that, all else being equal and assuming you are not bottoming out, increasing roll stiffness of either axle should increase overall grip and responsiveness up to a point, but it also means that outside tire on that axle is doing more of the work and will be overloaded sooner. So if the car is oversteering too much and you add a slightly stiffer front bar, you could in theory make it more balanced and gain overall grip.

I think the issue a lot of people run into is that the aftermarket front sway bars are very stiff compared to stock and designed to be run with an equally stiff aftermarket rear sway bar. So if you just do the front, you could still in theory be quicker, but if you don't adjust your driving style to account for what may now be an understeer bias, you are just going to overheat your front tires, which will of course make you slower. If I were only going to do the front, I would look for the softest sway bar on the softest setting (which would still probably be noticeably stiffer than stock).
From what people who know better than I have told me, stiffer suspension helps with transitions but usually results is a reduction of overall grip.
Most of us find a balance in how much overall grip we're willing to give up versus response of the car.
For me, I take a look at the tracks I run and determine how much steady-state grip I'm going to need, on average, versus transitioning.
Right now, my stock setup has worked really well together and I think, in my case, I would lose too much grip by swapping to a different sway bar.
I would obviously have to do back to back comparisons to see for sure, which I might do next year, once I have time to play around and the weather is better.
 

Rta95

Well-Known Member
First Name
Rahat
Joined
Jul 13, 2022
Threads
8
Messages
143
Reaction score
81
Location
Somerset, NJ
Car(s)
2022 Toyota Supra 3.0 Premium
More questions from me, sorry lol. So I'm just following the handling packages Jackie Ding has on his site to slowly upgrade my car. Question I had is, is there anything else you'd add to the handling package 2 (https://phdracing.store/collections...s/ta90-level-2-package?variant=33198191313005) if your car was lowered on springs too? Figured not really but just wanted to be sure. I learn something new everyday from these forums and suspension geometry/physics is still something I'm wrapping my head around lol. And another question, is there anything from that package you don't think is actually entirely THAT necessary? Again to put in to context, I do autocross and a handful of track days/single lap time trials, but nothing that hyper competitive. All for fun really.
 

Evolution

Well-Known Member
First Name
Sean
Joined
Mar 10, 2021
Threads
14
Messages
1,886
Reaction score
3,096
Location
CA
Car(s)
21 Supra
Finally in a position to buy some 18 squared wheels now that the advans are sold.

T7/Apex are the two that offer a 18x10 squared setup for stock suspension, right?
I got some brand new sm-10s, 18x10 if you are interested. Still haven't decided if I am going to keep them. Haha.
 

racebuild

Well-Known Member
Joined
Jul 14, 2023
Threads
1
Messages
215
Reaction score
215
Location
USA
Car(s)
BMW
stiffer springs than people suggest and front and sway sways both on max
I slide through some corners when doing a time trial or hot lap and have to counter steer power on.
I have over 10 years of chassis setup experience 80% of them being BMW and never have I needed to go anything more than full soft setting on sways with preset adjustments. On the race sway bars which are hollow bar slider/blade type the most weā€™ve needed was ~10% over full soft.

For street style (preset adj) sway bars Iā€™ve always looked for the smallest increase over factory that is adjustable, purely for fine tuning if I needed it.

I also donā€™t over spring the car, with a race damper (jrz/mcs) you donā€™t need a ton of spring especially if youā€™re on a street tire.

Over sprung/overly stiff roll couple = increased force to the tires. To keep it very simple higher roll stiffness = less gripā€¦ the reason youā€™re sliding in/out of corners.

Roll stiffness is not to be confused with chassis stiffness, or roll center.

Iā€™m already working on something to settle the rear end, itā€™s something Iā€™ve applied to every bmw chassis Iā€™ve setup in the past that wanted the ā€œextra sauceā€.
 
Last edited:

Joker328

Well-Known Member
First Name
Chris
Joined
Nov 9, 2022
Threads
1
Messages
98
Reaction score
88
Location
NoVA
Car(s)
2023 Red 3.0 Premium MT
I use this since all of my hand tools are DeWalt. This runs off the cigarette lighter or a battery. I set the PSI and it runs to that pressure and stops. It even adds as extra 0.2 psi or so to compensate for air loss when you remove it lol

download (2).jpeg




From what people who know better than I have told me, stiffer suspension helps with transitions but usually results is a reduction of overall grip.
Most of us find a balance in how much overall grip we're willing to give up versus response of the car.
For me, I take a look at the tracks I run and determine how much steady-state grip I'm going to need, on average, versus transitioning.
Right now, my stock setup has worked really well together and I think, in my case, I would lose too much grip by swapping to a different sway bar.
I would obviously have to do back to back comparisons to see for sure, which I might do next year, once I have time to play around and the weather is better.
Yeah, I edited my original post as I think I confused some things. One important thing I have read is that "Lateral load transfer in one axle will change with the proportion of the roll stiffnesses on that axle, not the roll stiffnesses themselves." So putting proportionally stiffer sway bars on both axles shouldn't do much to overall weight transfer/grip, but if stiffening one or the other improves balance between front and rear, you may actually be faster.
 

FLtrackdays

Well-Known Member
First Name
Mark
Joined
Mar 6, 2022
Threads
30
Messages
3,598
Reaction score
3,580
Location
the least restrictive State in the USA
Car(s)
2022 Supra 3.0, ND MX5 Club, VW GTI MK7.5
What do you all use to air up at the track?

Iā€™m considering buying a compressor but donā€™t want one that sucks.

Also, any suggestions for starting tire pressure for PS4S on track?
Some to consider:
https://www.roadandtrack.com/gear/g44735782/best-portable-tire-inflators/
Personallyā€¦ Iā€™d start my pressure at 30-32 psi in the early colder morning. As I get faster & the day gets hotter, begin to bleed the pressure down all day long to maintain less than 36 psi hot. A lot of it is feel. Definitely go lower if you start to feel too much slide.

So, lowering springs and sway bars? Or does someone make a standard spring for OEM struts that is more stiff?
Stuff you already know but to share with others. ā€œIf you plan on attending any track events, a set of coilovers is a much better purchase than lowering springs.ā€œ - Completely agree with them (link below) & wish I did it sooner. Bonus: the Ohlins come with linear springs. Great combo with my sway bars.

https://www.vividracing.com/blog/lowering-springs-vs-coilovers-whats-right-for-your-car/
 

Deighvid

Well-Known Member
First Name
Deighvid
Joined
May 25, 2021
Threads
19
Messages
667
Reaction score
738
Location
Los Angeles
Car(s)
2021 3.0 Supra Premium
Finally in a position to buy some 18 squared wheels now that the advans are sold.

T7/Apex are the two that offer a 18x10 squared setup for stock suspension, right?
You need spacers for the wheels to clear the stock suspension.
 

Islindur

Well-Known Member
Joined
Aug 25, 2018
Threads
18
Messages
606
Reaction score
586
Location
Poland
Car(s)
Had:Yellow 2l Have: Red 3l
Wonder if running only front Eibach sway on soft (194% increase over stock) with revalved Ohlins R&T with rates around 650/1100, square 295 r18 tire and full verus aero (normal splitter) would still be understeery... When I did rear sway on my 2.0 as an addition to front (coz well, understeer with only front) car became very tailhappy with stock dampers/eibach springs so dunno if I wanna install rear again on new 3.0 Supra.... but dont want the car to be understeery again, wonder if higher spring rates at bak and square tires would be enough counter balance :)
Any opinions?
 
Last edited:

Rocksandblues

Well-Known Member
First Name
Bob
Joined
Sep 21, 2020
Threads
41
Messages
2,247
Reaction score
3,961
Location
Virginia
Car(s)
2021 Supra, e46 M3, diesel BMW e90, GL450
4335B8F8-3FC8-477D-B522-8DE91B817C14.jpeg


this thing absolutely walked me on the straight but I was faster on every other part of the track. He is a good driver- has been to several race schools
At my home track I have a top ten time of all time Only members that are faster are VERY good drivers- one has a c7 ZR1 and the other races a 911 cup car in an actual series.
Only had a Garmin a couple months but in top 5 where ever I go (I know not everyone uses it- but summit main has 130+ so far this year)
My point is less douch bag and I guess defending or proving my set up is fast.
I know there are faster cars and faster drivers !! I concede there are different ways to set up a race car.
If you watch nascar on road tracks. They jump curbs- a wheel or two come off, but they remain level and they absolutely slide thru corners when pushing. I am NOT a nascar level driver.
It works for me but I will absolutely get an MCS coil set up before long Then I might start bragging;)
 

Isaleus

Well-Known Member
Joined
Oct 5, 2022
Threads
6
Messages
214
Reaction score
301
Location
Michigan USA
Car(s)
CUL A91-MT , 2008 Orange GMC Canyon
Signed up for a whole weekend track day that is a month away with 5/32nds of tread on my rears with the original pilot super sports on them. Fronts still have plenty 7/32nds

Should I be worried about cooking them the first day and failing tech the second day due to the tires?

If so I can check them 2 weeks before the event and slap on a new set of rears but just trying to get the most life out of the originals as I can.
 

Traxion

Well-Known Member
Joined
Oct 6, 2021
Threads
1
Messages
233
Reaction score
355
Location
Southeast, USA
Car(s)
2022 Toyota Supra 3.0 Premium
Should I be worried about cooking them the first day and failing tech the second day due to the tires?
The fronts will take more of a beating than rears if it's a turn heavy course. I ran oem PSS for a while and they'll start chunking the edges before you use up tread. I'd say you should be fine. Most groups do a single tech inspection for the whole weekend so it'd be up to you to check them and deem them safe or not. If you haven't tracked much before honestly I would say you're not going to find the real limit anyway. And if you overdrive and spin out you have fundamental issues that you need a coach for.
 

kaj

Well-Known Member
First Name
Jason
Joined
Aug 6, 2022
Threads
35
Messages
2,072
Reaction score
2,408
Location
Fresno, CA
Car(s)
2021 Supra
The fronts will take more of a beating than rears if it's a turn heavy course. I ran oem PSS for a while and they'll start chunking the edges before you use up tread. I'd say you should be fine. Most groups do a single tech inspection for the whole weekend so it'd be up to you to check them and deem them safe or not. If you haven't tracked much before honestly I would say you're not going to find the real limit anyway. And if you overdrive and spin out you have fundamental issues that you need a coach for.
at least worn tires are less likely to chunk :D
Sponsored

 
 




Top