Brake Review! Track Setup with Specs

I'll get to the list of details first:

 

Air Temp: 40F to 70F (Saturday-sunny and Sunday-partly cloudy)

Location: Virginia International Raceway, Full Course http://www.virclub.com

Data Log: Day 1 = 100.2 miles (30 laps, 4 sessions), Day 2 = 83.4 miles (25 laps, 3 sessions); 25 minute session intervals. Lap times are around the 2:20 to 2:25 range.. (slow car). The Porsche Carrera GT driven by Randy Pobst had a time of 2:02 on this course (yes, he slaughter me bad). Spec Miata driven by my friend comes in around a 2:16 to 2:17 range.

 

Tires: 235/40/18 Pirelli PZero Corsas Race Compound, 75% tread

Wheels: 18"x8.5" +48mm SSR Competitions Silver (15.0 lbs)

Rotors: Original Stock Rotors, never been turned, 37,200 miles old

Coilovers: Endless Zeal V6 Coilovers Standard 8kg/6kg springs, 32,000 miles old

Dampening: 4 out of 6 front, 4 out of 6 rear

Sway Bars: Cusco Vacanza Front 23mm, Cusco Vacanza Adjustable Rear @ 21mm; stock endlinks

Braces:STi Titanium Front Strut, Cusco Rear Lower-arm Braces

Alignment: Front (~ -3.2 camber, 1/8" toe out, +7.0 caster), Rear (~ -1.7 camber, 0 toe)

Tire Pressure: 37 psi front cold, 35 psi rear cold; 36 psi front hot, 33 psi rear hot

Brake Lines: Techna-fit Stainless Steel lines, Stock calipers

Brake Pads: Carbotech XP10 front, Carbotech XP8 rear

Brake Fluid: Motul RBF600

Bedding: As per Carbotech's track bedding procedure (7/10 braking followed by 2 hot laps of 10/10 braking, 30 minute cool down).

Engine: Stock motor, no addtional work (no UTEC and no change in boost). Installed Blitz LM Air Filter

Exhaust: Greddy Evo2 Catback Exhaust, stock cat, stock uppipe and downpipe.

Oil: Running Pennzoil Conventional 10w40. No loss or consumed oil.

Tranny: Stock tranny, running Redline MT75w90 in tranny and rear differential

Fuel: Exxon 93 Oct @ $2.22/gallon at Danville, total consumption of 12.5 gallons in Day 1, 14.5 gallons Day 2.

 

Track Notes:

Turn 1 (10/10 braking effort) = "Horse Shoe, double apex", Speed of 125 mph down to 35 mph (on stock odometer readout, no actual laptop data-logging was at hand at the time), takes about 500 feet of braking when brakes are cold.. the brakes warm up and can do down to 350 feet with plenty of safety margin ahead.. 2 downshifts (5 to 3).

 

Turn 3 (8/10 braking effort) = "NASCAR bend", Speed of just 100 mph down to 75mph, easy driftable left hander, possible of understeer if you turn in too fast. You can stay in 4th gear through here in the GT.

 

Turn 4 (10/10 braking effort) = "Left Hook" with a downshift into 3rd gear. Easy to lock up the brakes, since it's it a late apex.

 

Turn 10 (7 to 8/10 braking effort) = "South Bend" coming over the crest with a medium left-hander followed by off-camber steep down hill (think 15% grade). Speeds at the top of South Bend in the GT can be anywhere around 100 mph to 110 mph and slows down to 85 upon entry and exit.

 

Turn 11 (7 to 8/10 braking effort) = Coming up to the uphill braking zone doesn't require that much braking, just a single downshift into 4th is fine.

 

Turn 12 (5 to 6/10 braking effort) = Downshift into 3 before turn-in and just power past the infamous "Oak Tree"

 

Turn 14 (10/10 braking effort) = Heading into "Roller Coaster" is a compound braking set up if you want to carry some more speed over the crest between 14 and 14a. A good entry speed prior to braking in the GT is 120 mph.. I have yet to hit 130 mph in that car going through the uphill back straight. Parts of the braking zone is up hill and you can brake as late as the middle of brake marker 2 and 3 (250 ft?) prior to the turn-in for 14. From here, you should be carrying about 75 to 80 mph into 14a where you can use another 10/10 braking to set up the car for turn 15. 2 downshifts (5 to 3) prior to entering 14.

 

Turn 16 (10/10 braking effort) = Entering into "Hog Pen" can be messy due to the inside dip from turn 16 to the entry of turn 17. Speeds for 16 is near or over 85 mph. Slow the car down to 65 mph and go from there and you should be able to make it a constant radius and foot to the floor once you finish turn 16 (as my foot is to the floor through all of 17, silly turbo AWD car). Anymore speed and you'll end up tracking out too early since you need some throttle going into turn 17 with the back end planted down and the nose of the car tucked in neatly.. it's is not a smart corner to try to oversteer/drift the car to aim it.. it's an increasing radius turn, dont need to point the car more than it needs to be. If you got the braking, turn-in and track out correctly, you should be at the top of 3rd gear before you even finish tracking out on turn 17. You might need to upshift between the apex and track-out point of turn 17.

 

Map of the Track:

http://www.virclub.com/vir/images/track/track_map.jpg

 

Personal Notes:

Awesome! No fading at all, plenty of bite!!! Great pedal feel!! Even locked up the brakes before the ABS came on!! This car doesnt need bigger brakes, it just needs more tire! If the day was hotter range of 65F to 95F, I would get slotted brakes or wider brake rotors and wider calipers to hold in the brakes. No need for brake ducts since it was cold enough as it is. No warping of the rotors either.

 

Shameless Sponsor Plugs:

Thanks to Racecomp Engineering, GTWorx, TireSwap, BrakeSwap, Radial Tire Co., and RaceApeel for all their support and help.

 

Pics will be posted later in the week.

 

In-car video is here:

Click here to watch VIR-GT-Driver-In-car

Awesome. This is exactly what I want to see.

 

I need to get out to the track again with some better brakes.

Very good info!!

 

I have a set of Carbotech Panther Plus pads on the bench that are going in this week, but it appears that I will need a rotor cleanup (24.5K miles on stock pads) after two DE-type track days (Putnam Park and Gingerman) plus a few drag days (I take the first return road). Rear rotors look rougher than the fronts.

 

The stock brake pads reminded me of the stock Ford Motorcraft pads that I used on the SHO for track events (as in: good on the street and for the first few laps of a track session). With the Exalto PE2 tires, the brakes worked well until they faded. I figures that I would use the Panther+ on the street, and was considering XP8 & 10 for the track if the P+ didn't work out to be good on the track (but I'm sure they will be fine).

Thanks Xenonk.

 

This should be enough to prove that the stock calipers and rotors are good enough, and it's the stock pads that can't even handle mild spirited driving, at least for my driving.

 

Therefore if you aren't satisfied with the stock brake performance or you get "brake shake" or "rotor warp" with your driving, try different pads first.

nice writeup. i've only done vir on a bike, but it's interesting to see the differences in techniques and speed (corner and straightline). is that right that you're down to only 35 mph entering T1? i crashed there earlier this year partly because of all the crap you car guys lay down.

nice writeup. i've only done vir on a bike, but it's interesting to see the differences in techniques and speed (corner and straightline). is that right that you're down to only 35 mph entering T1? i crashed there earlier this year partly because of all the crap you car guys lay down.

 

I can do it around 45 mph, but there's no point for my car since I am just fighting the wheel and playing with the throttle (and it's a waste of tires).. I can get more speed out of the car (slow-in, fast-out) if I just be full on after I pass the ultra late apex of turn 1.. I can be on the gas all the way through Nascar bend.. sometimes I will shift into 4th on the little straight between the left-hand kink (sometimes I cheat it to the left) and turn 2.. I am about just a little bit over 95 mph in that section.. I have enough speed to carry through turn 3 and lay hard on the brakes with a downshift into 3rd.

 

Btw, near the end of Sunday, a few cars went off on turn 1 (I think an Evo did because he ran out of brakes).. I am sure he's doing well over 150 mph because I gave him the point-by at 17 and by the time I got around turn 3, he was just creeping out of the run-off at turn 1 A fast lap time is making sure you can at least stay on the track longer

Do your tires actually lose pressure as they heat up?

Do your tires actually lose pressure as they heat up?

 

+1!!

 

Wondered about that myself!

I bled them after the hot session.. there's no point balloning the tire and not checking it after a hot run.

Why did you bleed them? were you getting a soft pedal?

 

FWIW, I have never had to bleed during a track day, although others have.

 

Also (and I know that this would be a never-ending thread on this forum) a couple of folks I know, who are serious track and long-distance race junkies, do not like Motul 600 at all. Besides not seeming to show any more fresh (dry) resistance to boiling, they have felt that it gives a softer pedal compared to others like the more pedestrian ATE (which is 1/2 the price).

 

I was an pretty steady ATE user, but have had excellent success with the Valvoline Synthetic, which is 1/2 the price of ATE (now $5.99 at AZ), and gives up almost nothing in performance, besides being available about everywhere (great when most tracks are in the middle of nowhere!!). Here's a list from a few years ago:

 

-------------------------------DRY----WET

Castrol LMA DOT 3/4-----------446 311

Ford Heavy Duty DOT 3---------550 290

Valvoline Synthetic 3/4----------502 343

ATE Super Blue Racing-----------536 392

ATE TYP 200--------------------536 392

ATE SL DOT 4-------------------500 329

Motul Racing 600----------------585 421

Castrol SRF---------------------590 518

Performance Friction-------------550 284

Why did you bleed them? were you getting a soft pedal?

 

FWIW, I have never had to bleed during a track day, although others have.

 

Also (and I know that this would be a never-ending thread on this forum) a couple of folks I know, who are serious track and long-distance race junkies, do not like Motul 600 at all. Besides not seeming to show any more fresh (dry) resistance to boiling, they have felt that it gives a softer pedal compared to others like the more pedestrian ATE (which is 1/2 the price).

 

I was an pretty steady ATE user, but have had excellent success with the Valvoline Synthetic, which is 1/2 the price of ATE (now $5.99 at AZ), and gives up almost nothing in performance, besides being available about everywhere (great when most tracks are in the middle of nowhere!!). Here's a list from a few years ago:

 

hrm... I used to use ATE and switched over to RBF.. Ive found it absorbs better and I need to flush less. Pedal feel did not change too much between the two, but Ive also heard of "race junkies" who think it makes it softer.

 

The Valvoline stuff does pretty well on my street cars, but I havent tried it on track so I cannot comment there.

I bled them after the hot session.. there's no point balloning the tire and not checking it after a hot run.

 

Bleed off tire pressure you mean?

i am really suprised a spec miata had better times. was it your first time on the track? and was the miata on spec tires (shaved street or smth) or r tires?

(this is not in any way meant to be negative, its just that spec miatas are not THAT fast, they just handle well, so I am suprised).

good to know about the brakes, I can't wait till break-in is over and see if i can turn some good times at the track.

Those are some funky springrates for the rear. With the lever ratio on our rear suspension I wouldent be surprised if that would be equivilant to a 3-4 kg (wrx equivilant) springrate.

 

Ever swap coils F-R?

Assuming the drawing is to scale. The spring mounting point is 3/4 of the trailing arm length away from the fulcrum point.

 

It looks as if we have a 4:3 lever ratio in the rear suspension

 

Which means a 6kg springrate in the rear would be the equivilant to using a 4.5kg rear springrate in a chapman strut type suspension which uses a 1:1 lever ratio.

 

Swapping them front to rear would yeild 6kg fronts and 6kg rear (when corrected to a 1:1 ratio).

 

Keefe must be driving the living sh*t out of this thing to keep it from understeering. Or maybe running some mad angry camber in the front.

04 - Rear Arm.pdf

i am really suprised a spec miata had better times. was it your first time on the track? and was the miata on spec tires (shaved street or smth) or r tires?

(this is not in any way meant to be negative, its just that spec miatas are not THAT fast, they just handle well, so I am suprised).

good to know about the brakes, I can't wait till break-in is over and see if i can turn some good times at the track.

 

That SpecMiata must be movin! I usually see SpecMiata times around the 2:20 - 2:22 range? 2:16 is really fast... you sure you have that time down right?

Why did you bleed them? were you getting a soft pedal?

 

 

No, i meant I bled off my tire pressures after the hot run.. I didnt want to run on 40 psi tires on the next run (which was like another 40 mins to an hour later)...

That SpecMiata must be movin! I usually see SpecMiata times around the 2:20 - 2:22 range? 2:16 is really fast... you sure you have that time down right?

 

 

I watched my tape last night and I am about to post it up.. I am doing about just 2:20 to 2:22 for a brisk drive for the lap.. the Spec Miata driven by my friend is a fast racer, he's been racing probably longer than Alex and Vic H. combined. And yes, that time is correct because he has his transponder equipment with him and showed me some clear track lap times.. remember, when you're in a race, you have traffic to fight for, so it's not always a clean track to work with. There's something about him going into turn 3 and 4 really hot.. I am assuming he's foot to the floor blasting the uphill esses at top speed basically.

i am really suprised a spec miata had better times. was it your first time on the track? and was the miata on spec tires (shaved street or smth) or r tires?

(this is not in any way meant to be negative, its just that spec miatas are not THAT fast, they just handle well, so I am suprised).

good to know about the brakes, I can't wait till break-in is over and see if i can turn some good times at the track.

 

I've been on this track more than a few times and logged in about close to 800 miles now. If I push my car some, I know I can get into the 2:18s with the GT without any real issues.

 

The SpecMiata is on R-compounds shaved. My friend who races the car is one fast driver, and he can definitely keep up with a stage 2 WRX with full suspension work and R-compounds as well that's driven by a respectable fast driver.

Swapping them front to rear would yeild 6kg fronts and 6kg rear (when corrected to a 1:1 ratio).

 

Keefe must be driving the living sh*t out of this thing to keep it from understeering. Or maybe running some mad angry camber in the front.

 

I havent swapped the springs, and I dont plan to because I am using this for braking purposes to keep the car as level as possible when going really hot into the the turn.. my instructor wasn't comfortable with me going in so hot at 125 to 130 into the 10/10 braking zones and wanted me to start braking sooner.. well, needless to say, the car can stop.

 

I will be going for some 12/10 spring setup for the GT when I get the Zeals rebuilt. I do run some nice camber.. and when you watch my video, I am not really driving the crap out of the car, it's just being smooth to get the car to transfer the weight nicely to the rear and get the rear end to squat some and let the tires up front do some steering for me while still just a little bit of stiffness and weight over the front to keep the grip at full max. The car doesnt understeer if you use throttle steering more often, or better yet, trail braking as I am use to it by now.

 

I do all of my "catching up" using the brakes.. you can always catch a person into the corner if you use your brakes to its fullest. There were a few cars that just didn't carry that kind of speed to go into the hot turns and that's where I make up my ground.

bump, video is up and the link is at the end of post #1.

Yikes! Full face Helmet in a Airbagged CAR!

 

"DATE: November 16, 2004

FROM: National Staff

TO: All Participants

SUBJECT: Airbag Advisory

 

It has been brought to the attention of SCCA Technical Services that the use

of full-face or closed-face helmets while driving vehicles with active airbag

restraint systems may result in injuries in the event of a crash that deploys

the airbag. Because of the location of the steering wheel relative to a

driver’s position, the airbag axis is on a level with the driver’s chin. In a

crash with airbag deployment, contact with the chin area of a full-face

helmet can be so powerful “that the risk of fractures to the jaw cannot be

ruled out“ (Hubert Gramling, FIA Institute, FT3/AF, 18.5.1999). This applies

to vehicle that may be used in Solo, RallyCross, High Performance Car

Control Clinics, etc.

 

Therefore, it is highly recommended that full-face helmets not be used in

vehicles with functional airbag systems. Potentially more restrictive language

is currently being considered for 2005, which could appear in an early 2005

issue of FasTrack. If you have any questions, please contact the SCCA at

(800) 770-2055."

 

 

http://www.mohud-scca.org/Info/download/PB%2005-01%20Airbag%20Advisory.pdf

 

SCCA discussion.

 

http://www.scca.org/garage/forum/forum_posts.asp?TID=1208&PN=1

 

Just looking out for ya bud.

No, i meant I bled off my tire pressures after the hot run.. I didnt want to run on 40 psi tires on the next run (which was like another 40 mins to an hour later)...

 

DOH!! Sorry!!

 

I lost track of the intent of that thread!!

 

Interesting, as I had found 40 psi to work for me, and could have used a bit more in the front for Turn 10 a Gingerman:

 

http://www.na-motorsports.com/Tracks/MI/Gingerman.html#TrackMap

 

However, I am also still with a stock suspension, stock alignment, and street rubber on 17x7.5" Rotas.

Yikes! Full face Helmet in a Airbagged CAR!

 

"DATE: November 16, 2004

FROM: National Staff

TO: All Participants

SUBJECT: Airbag Advisory

 

 

Don't worry about it. There were probably more posts and emails flying around about this time last year (on that subject) than there was Spam email!!

 

It is not the issue that they have made it out to be. if you are running a quality Snell SA helmet, the odds of a chin break from the airbag are pretty slim. You are still safer than with an open-face helmet. Also keep in mind that track incidents can involve secondary (or more) hits, and the airbag is a one-time deal.

 

I personally wouldn't use anything but a full-face helmet for either the motorcycle or the car, airbag or not.

Yikes! Full face Helmet in a Airbagged CAR!

 

"DATE: November 16, 2004

FROM: National Staff

TO: All Participants

SUBJECT: Airbag Advisory

 

It has been brought to the attention of SCCA Technical Services that the use

of full-face or closed-face helmets while driving vehicles with active airbag

restraint systems may result in injuries in the event of a crash that deploys

the airbag. Because of the location of the steering wheel relative to a

driver’s position, the airbag axis is on a level with the driver’s chin. In a

crash with airbag deployment, contact with the chin area of a full-face

helmet can be so powerful “that the risk of fractures to the jaw cannot be

ruled out“ (Hubert Gramling, FIA Institute, FT3/AF, 18.5.1999). This applies

to vehicle that may be used in Solo, RallyCross, High Performance Car

Control Clinics, etc.

 

Therefore, it is highly recommended that full-face helmets not be used in

vehicles with functional airbag systems. Potentially more restrictive language

is currently being considered for 2005, which could appear in an early 2005

issue of FasTrack. If you have any questions, please contact the SCCA at

(800) 770-2055."

 

 

http://www.mohud-scca.org/Info/download/PB%2005-01%20Airbag%20Advisory.pdf

 

SCCA discussion.

 

http://www.scca.org/garage/forum/forum_posts.asp?TID=1208&PN=1

 

Just looking out for ya bud.

 

 

Thanks, I know about this, that's why you pull out the fuse for it