Brake fluid for HPDE

[gcmak]

I have 9600 miles on the original tires, mostly commuting and some back road driving. I wont feel bad if I kill them off in A HPDE but I don't expect to. I remember when they repaved Summit Main maybe 12 years ago, there was a ton of grip, I corded a R888 in one day in a track spec Miata.

Start higher and work your way down...would suck more to start your day with excessive wear and needing to manage the tire for the rest of your day.

Sponsored

 

[Gcole]

I never tracked a car that had tire temp, on the dash, I am curious on what ideal hot temps are?

 

[Nocturnal LE]

I never tracked a car that had tire temp, on the dash, I am curious on what ideal hot temps are?

uhh where can we see tire temps??

 

[strohw]

uhh where can we see tire temps??

Same screen you view tire pressure.

 

[Nocturnal LE]

Same screen you view tire pressure.

wow don't know how I missed that. Any idea where exactly the temp sensor is? middle of the tire I'm guessing?

 

[gcmak]

wow don't know how I missed that. Any idea where exactly the temp sensor is? middle of the tire I'm guessing?

I shared a photo in my post along with the fact that the system automatically adjust the recommended front / rear tire pressures in accordance with temps. https://www.supramkv.com/threads/brake-fluid-for-hpde.9128/post-131857

The temp is just taken in general as it's measured by the TPMS sensor. It's not a pyrometer measurement.

 

[Gcole]

So I had my free NASA Run on Sat at Summit Main. I haven't run on stock tires and pads on a car since 2002 and I was in a fast group with instructors and time trial cars and open passing and frankly I haven't run at Summit Main since 2013 so I am a little rusty.

Here are some observations, with cold pressure a little lower than stock 36 PSI, the first run at about 2 laps in I started getting wheel spin on 2 of the slowest right hand corners, turn one and turn 6 in the carousel. Tires were 42 hot and 190 front and 150 rear. '

I dropped to 35 hot and I drove faster on the 2nd session in braking and cornering, trying to use more track etc, I was having a tough time getting the power down I kept on lighting up the rears and had a few moments catching the car, I actually turned on VSC about halfway though just to settle the car down, the power was great and I could leave in 4th and 5th on the slower corners and ride the torque.

I went lower on the 3rd session on the tire pressure 32 hot and it was better on the rear, lost some grip on the front and it would push some, I passed a few cars into turn 3 on the inside but just had to give it back as I couldn't carry the speed to make the corner and keep up the momentum.

I skipped the 4th session as it was going to be at 6:00.

Hit 145 a few times on the main straight and would hit 110 under the bridge before turn 10, so there is tremendous potential in the car it just needs better tires, pads, maybe a stiffer front sway bar and stiffer shock and perhaps aero.

Its like a S2000 with a ton more torque, A S2000 would not give you much notice before wanting to spin, this car was was better in that regard it starts to slide a bit.

I had a few other track cars over the years, 2 Corvettes a S2000 and A Miata. The Miata and S2000 were caged with race seats, the S2000 had a rear wing.

 

[nibble]

sway bar front and back helps a lot. Also, with lower tire pressure, although it will give you more grip, you will observe heavier wear on outside of the tire. as for brake pad, Hawk DTC-60 gives a lot of grip but may wear out rotor a lot. also, if you are using stock rear brake pad, it will yield some understeer during braking.

 

[kurumi]

So I had my free NASA Run on Sat at Summit Main. I haven't run on stock tires and pads on a car since 2002 and I was in a fast group with instructors and time trial cars and open passing and frankly I haven't run at Summit Main since 2013 so I am a little rusty.

Here are some observations, with cold pressure a little lower than stock 36 PSI, the first run at about 2 laps in I started getting wheel spin on 2 of the slowest right hand corners, turn one and turn 6 in the carousel. Tires were 42 hot and 190 front and 150 rear. '

I dropped to 35 hot and I drove faster on the 2nd session in braking and cornering, trying to use more track etc, I was having a tough time getting the power down I kept on lighting up the rears and had a few moments catching the car, I actually turned on VSC about halfway though just to settle the car down, the power was great and I could leave in 4th and 5th on the slower corners and ride the torque.

I went lower on the 3rd session on the tire pressure 32 hot and it was better on the rear, lost some grip on the front and it would push some, I passed a few cars into turn 3 on the inside but just had to give it back as I couldn't carry the speed to make the corner and keep up the momentum.

I skipped the 4th session as it was going to be at 6:00.

Hit 145 a few times on the main straight and would hit 110 under the bridge before turn 10, so there is tremendous potential in the car it just needs better tires, pads, maybe a stiffer front sway bar and stiffer shock and perhaps aero.

Its like a S2000 with a ton more torque, A S2000 would not give you much notice before wanting to spin, this car was was better in that regard it starts to slide a bit.

I had a few other track cars over the years, 2 Corvettes a S2000 and A Miata. The Miata and S2000 were caged with race seats, the S2000 had a rear wing.

I was in HPDE 1 with the rest of the Supras and for both sessions, I ran out of pad by the second lap. I had swapped fluid in using Motul 660 but stuck with the OEM pads to see how they would hold up; they didn't.

Granted, I am running a Pure 700 (using a stock turbo flex fuel tune) and on e40 fueling so I was putting down more power than the stock pads were meant to stop for. I had similar results when I ran the car on stock power last year on Main but it was laps 3 onward when I ran out of brakes.

Gonna try swapping to CSG CP pads for the front and rear to see if that holds up better.

 

[Gcole]

I was in HPDE 1 with the rest of the Supras and for both sessions, I ran out of pad by the second lap. I had swapped fluid in using Motul 660 but stuck with the OEM pads to see how they would hold up; they didn't.

Granted, I am running a Pure 700 (using a stock turbo flex fuel tune) and on e40 fueling so I was putting down more power than the stock pads were meant to stop for. I had similar results when I ran the car on stock power last year on Main but it was laps 3 onward when I ran out of brakes.

Gonna try swapping to CSG CP pads for the front and rear to see if that holds up better.

I never ran out of brakes, just didn't care for the long travel. I measured my pads before the event looks like the rear pads wore out 2x more than the front. Might have something to do with the VSC turned on also. Good pads are going to chew up rotors, its always a tradeoff.

 

[kurumi]

I never ran out of brakes, just didn't care for the long travel. I measured my pads before the event looks like the rear pads wore out 2x more than the front. Might have something to do with the VSC turned on also. Good pads are going to chew up rotors, its always a tradeoff.

What I meant was that the stock OEM pads became overwhelmed and stopped being effective in slowing down the car as quickly after several hard pushes on the brake pedal. They operated normally once cooled down and on the drive home. I still have a lot of brake pad material left.

 

[nibble]

I never ran out of brakes, just didn't care for the long travel. I measured my pads before the event looks like the rear pads wore out 2x more than the front. Might have something to do with the VSC turned on also. Good pads are going to chew up rotors, its always a tradeoff.

i didn't have any issue /w stock pad /w 20+ trackdays. If rear pad wears out faster than front, it is VSC/Traction control kicking in more often than needed. If you are smoother, TCS/VSC is less likely to kick in and save rear brake pads. - I'm still on my original rear brake pads and have not yet found suitable replacements yet..

 

[Rocksandblues]

i didn't have any issue /w stock pad /w 20+ trackdays. If rear pad wears out faster than front, it is VSC/Traction control kicking in more often than needed. If you are smoother, TCS/VSC is less likely to kick in and save rear brake pads. - I'm still on my original rear brake pads and have not yet found suitable replacements yet..

Went through my stock pads and the fade scared me in my first 3 tracks days. I have 16 hard all day 6 sessions on track pads, endless and solid lines and the difference is dramatic.

Guess it is how hard you push too

 

[Gcole]

i didn't have any issue /w stock pad /w 20+ trackdays. If rear pad wears out faster than front, it is VSC/Traction control kicking in more often than needed. If you are smoother, TCS/VSC is less likely to kick in and save rear brake pads. - I'm still on my original rear brake pads and have not yet found suitable replacements yet..

I did turn on the VSC just so I could keep the tank slappers down, TC was always off. So that certainly did some damage, I will get some time in a few days and measure what's left.

 

[nibble]

Went through my stock pads and the fade scared me in my first 3 tracks days. I have 16 hard all day 6 sessions on track pads, endless and solid lines and the difference is dramatic.

Guess it is how hard you push too

most of the tracks I go to, NJMPs, Palmer, Pocono, Watkins Glen, & ETC, there's only 2~3 hard braking zones. so places you go to may have more. I do push it to about 80% only because I have passengers most of the time but enough to keep /w Corvettes and Porsches.

Sponsored