2019GSTX

OK, this is somewhat of a continuation of my quest for knowledge that I started when asking questions in the Track Day Fluids post. I rec'd some great help in answering my queries about brake fluid and what to use when I run a few hot laps down at COTA in July. This isn't a full on track day, just 30 minutes of running some warm up laps and a few hot laps around the F1 circuit. Based upon y'alls advice I'm going to flush the brake system with Motul 600 before I head down to Austin and then when I get back I'll flush again with factory fill.
Now for my other questions, please bear with this nOOb.
1) My GS has the J56 brake package and I'm currently running Powerstop pads for low dust. Will it be OK to run these pads at the track for a few laps or should I swap over to some track day pads? Mind you, I will have no way to swap out pads after the event and would be driving 3.5 hrs to the track and back home afterwards.
2) Why does the owners manual have the following caution: Performing the brake burnish procedure on a "base" brake system can result in brake damage. Am I to assume that J56 is not a base brake system?
3) Did you guys with a GS/J56 brake system receive the additional brake hardware for track day events, i.e. cooling ducts, blocker rings etc? I did not with my 2019. Maybe I need to go back to the dealer and ask where my stuff is at??
4) I have the car lowered all the way down on stock bolts. Should I run them back up a bit in anticipation of the event, or any event in the future? Any clearance issues you guys are having with the car lowered all the way down (I'm running stock summer only tires).

Fish, Goat, JMII - thanks for y'alls help so far...and thanks everyone for whatever advice you can provide. I just wanna have some fun and not screw up my car in the process!

X25

I run race pads year round. It'd increase rotor wear in the long term, but you end up wanting to replace rotors due to too many cracks before wear, anyway, especially if you do at least a handful track days a year.

Yes, I'd highly recommend replacing those pads with proper track pads. Perhaps it'd work out with those (if you're easy on the car), but why risk it?

The CCB burnish procedure is not for J56. The procedure for iron brakes is much simpler. To be honest, if you make easy few laps in your first session, they'd work great as a break in.

Your suspension might not work great if it's lowered all the way (since you might run out of suspension stroke), and you might rub, too.

I did receive and install the additional ducting on my car.

JMII

1) Which Powerstops? They make several compounds. For a few hot laps any decent brake pad should be OK, but you do risk glazing them over by exceeding their temperature range. If you can afford to swap them out it wouldn't hurt. Driving to and from the track on race pads is not a problem, just be careful as track pads often don't bite hard until they have some heat in them, so they might feel mushy under street conditions. Also track pads tend to squeal like a stuck pig so don't worry if they sound terrible especially when cold.

2) The purpose of brake burnishing is to transfer some pad material onto the rotors. You need some heat to accomplish this. I can't speak to the carbon brakes but with iron brakes the the procedure in the manual seems to be overkill to me. I've always just found an empty parking lot and done several, very aggressive stops to ensure things are seated properly. As X25 said your first few laps on track should allow them to come in nicely, they will smell horrible (and might even smoke) as you get them in the zone. I was once forced to go out on the track without doing any bedding because it rained the day before my event so I couldn't really work them hard enough beforehand.

3) I got my Z51 used and it had no cooling rings, but I don't see the need for them anyway as aftermarket rotors don't come with them. The car does have the ducts and I would make sure they are present to direct air flow to the calipers to help manage brake temperature.

4) May not be a bad idea to raise the car slightly, either that or just make sure you stay away from the curbs, rumble strips, alligators, sausages, or whatever the local term is for the painted and raised edge of the track in the turns. To run the proper line (and quick times) you normally need to at least clip these curbs but since you get no prizes for "winning" HPDE there is no reason to aggressively attack them. Discuss with your instructor regarding which ones are nasty, for example at Sebring you tend to avoid most of them unless you want to buy new wheels Due to the higher G-loads the car will be pushed down on its suspension way more then normal so rubbing is possible. I've yet to track my car since I switched wheels and lowered it so not sure myself how its going to react.

I wouldn't be too worried about your car. The C7 is meant to be tracked "as is" from the factory. My experience as a part time instructor is the things that go wrong at a track day are mostly temperature related: IE: brakes overheating, engine overheating, etc. Heck the nut being the wheel sometimes overheats the most So after a few hard laps take it easy, short shift, don't go super deep in the brake zones, etc. Make sure the car has a chance to do a proper cool down. This might be more then just a single cool down lap depending on when they throw the checked flag. I tend to drive around in the parking lot with the heater on full blast to help get engine temps back down to reasonable levels. Then I let it idle for 5-10 minutes while sitting the garage with the hood up with a close eye on the gauges. Follow the procedure for checking the oil level and check tire pressure as well between sessions. One quick warning: don't set your parking brake as the pads can stick because they get so hot. So bring a wheel chock to keep the car from rolling in the garage.

Finally - don't forget about yourself: drink plenty of fluids, have some energy bars handy, stretch out, etc. Driving hard is more physically and mentally challenging then you might expect, so ensure your body and mind are good. At first it will be overwhelming with so much new information and sensations to take in so quickly so don't let anything distract you from the task. Have comfortable clothes and shoes, along with a good fitting helmet. You will likely need to tweak your seating position as most people sit too far back when driving, so ask your instructor for tips on being situated properly.

Good luck and have fun... should be awesome event on such a high class track as COTA

2019GSTX

X25 and JMII,
Thanks much for your replies!
I'm currently running Powerstop Z26 on Forgeline wheels with Michelin A/S 3+ tires. I'm gonna pull those before I go and install the Powerstop track day pads and my stock GS wheels and summer tires, do a basic burnish. Its kinda ridiculous that Powerstop recommends a break in at 80mph multiple times in their break in video. Kinda hard to do that in the Dallas metroplex! I'll do a basic burnish as you guys have recommended, just like I did the current Z26's.
For the extra hardware, I didnt receive anything with my 2017 Z51 and didn't receive anything with my 2019 GS. I have an email into my dealer (Kerbeck) and we'll see what he has to say. I will check for the ducts but I'm not putting much faith in them being there.
I will raise the car a little bit just to prevent any possible rubbing.
10-4 on all the cool down procedures!

So, pre lap preparation will be:
Flush with Motul 600
Change pads to track day pads and burnish
Raise car height
Make sure ducts are installed
Raise oil qty .5 qt prior to being on the track and remove .5 qt afterwards
Torque and re-torque lug nuts

You guys prefer full face or open face? At COS we did open face but the windows were up and the A/C was on. At COTA it may be a windows down experience.

As for the at track advice JMII, I hear ya! All the pre track prep was learned at COS. The seating position was definitely a different situation. I'll check with the instructor for sure.

I plan on Go Pro'ing it since I have a cheap 'ol 1LT and no PDR.

Thanks again for your help, in reality you guys will be to blame when I'm hitting local track days burning thru brake fluid, brake pads, rotors, tires and track insurance!
Seriously, much appreciated.

wings19

A couple follow-up questions... I'm new to the Corvette, just picked up a GS from Denton, TX actually :P

I am a regular track rat in TX (had a GTR) but a couple things caught my eye in the manual and in OP's post:

If you go Motul 600, why flush back to OE fluid? Will you not be tracking again before the fluid may accumulate moisture?

Oil quantity - Are you guys actually adding oil for a track day then pulling it back out if necessary? How are you pulling .5qt out?

2019GSTX

First off, welcome, to another Texan!
With regards to the brake fluid flush, I think it goes back to the owners manual and the statement that they want you switch back after high performance driving. For me its more of warranty thing really. I'm not saying that I'll be swapping it out right when I get back but I will do it at some point when I get home. As for future tracking events, I probably wont be doing anything for awhile. I'm just getting going with all this track stuff and its gonna be awhile before I can jump into it head first, too many other projects going on.
For the oil question, I'll rig up something with my Mity Vac kit to pull the oil back out of the oil tank. again, just following the book for warranties sake.

Bill Dearborn

Bill

JMII

I run full face because the groups I run with (Chin Track Days) require that your windows remain down. They do this for safety reasons (broken glass) and for point by passing. My brother, who is a better track driver then me (Porsche Boxster GTS) got hit by a rock or big chunk of rubber on his shoulder one track day so that sealed the deal for him. I always ran full face with a shield because I wear contacts and all that high speed wind dries out my eyes badly.

I don't... but do ensure its at the very top of the hash marks (max) indicating the dry sump is completely full. I believe the .5 extra is to account for any excess oil burn at higher RPMs.

The attached Track Prep Guide for my 2014 Z51 doesn't mention the .5 extra but the Owners Manual does

2019GSTX

Bill - thanks for your input. Yes, a novice accurately describes my experience level. Have only done COS.
I think I will throw the stock pads back on there, they only have about 3k miles on them before I switched to the low dust Z26 ones. Powerstop does make track pads but I'll save the expense and use the stock ones.
There is a GM bulletin that I found that says the GS should have been delivered with the extra hardware. Still waiting to hear back from my sales guy about that!
I will run the car back up to original ride height just to avoid any issues

JMII - I agree, I'm not sure if we will be windows up or down @ COTA but I think I'll go full face anyway. The days I ride my Harley with half helmet I inevitably get hit with something in the face (minor). I don't need chunks of track debris flying at my unprotected noggin!
The oil wont be an issue, I'll run it high and pull back out what I need to before leaving.
Thanks for the Prep Guide!

You guys have a nice weekend!

acroy

I have nothing to add except:
Howdy Neighbor! I'm in Denton also.
Enjoy the track day!

2019GSTX

Howdy! What are you running around in Corvette wise? That way I'll know it's you when I see it.
I plan to....the way the heat is going there is no telling what July is gonna be like down there.

The HACK

Not that much of an HPDE guy, but with 20 years of driving on track under my belt and 13+ years riding passenger seat as counter balance weight, I think I might offer some unqualified advice.

1) My GS has the J56 brake package and I'm currently running Powerstop pads for low dust. Will it be OK to run these pads at the track for a few laps or should I swap over to some track day pads? Mind you, I will have no way to swap out pads after the event and would be driving 3.5 hrs to the track and back home afterwards.

You mentioned low-dust, so I assume you're using one of the organic or ceramic pads they offer. I've actually driven on track at high speeds (not the ones that do not require braking, by the way. Twisty tracks with left AND right turns) with ceramic/low dust pads. They are NOT ideal for track use. But your car will not magically disintegrate the second you use a low dust pad on track. But the answer to all questions are more nuanced than YOU think.

The real answer is it depends on what you want to do with it and what your skill levels are, and what track you're going. First, the reality is, organic and ceramic pads, while not designed for track use, is still capable of making about half dozen high speed stops before they will start to degrade. The issue with using low dust pads on track (and I lump most low dust pads here, because I've yet to see a low dust pad hold up to track abuse) is that they exceed their maximum operating temperature quickly. They're designed to work within a narrow, LOW temperature band. On track, your typical brake system can easily generate heat in excess of 1,000ºF, while typical STREET pads stop working past 500ºF. So once your pads heat up and heat up they will, they'll stop working, and what you'll find is, say, coming to a braking zone from a long straight, there's all of a sudden plenty of brake pressure but the car's not slowing down at all. The other problem is, when pads go over their MOT (Maximum Operating Temperature) they disintegrate quickly. Continue to operate and brake at extreme high temps and you'll increase the wear on these pads exponentially.

Anecdotal evidence: I once took a 350Z shod with Hawk Ceramics to a local track in the summer. Ambient probably in the high 90ºF range, with heavy 120+ to 50 and 100 to 30 braking zone scattered all around. By the 5th session (4 sessions a day, 20 minutes a session, 2 days), or first session on Sunday, these brand new ceramic pads had completely worn down to the backing plate...Not to mention the 3rd or 4th lap of the 2nd session, coming to the braking zone and having near zero brake into the last corner and having to shoot right off track and use the run-off.

HAVING SAID THAT.

For a complete noob? Just doing 3-5 lead/follow or parade like laps? You'd be hard pressed to need to swap pads. Just because I can easily push a car hard enough to disintegrate a set of pads, doesn't mean YOU will. This was done in an advanced intermediate group where I was the fastest driver in the group, in a relatively heavy car (3,500 lbs). I knew the pads weren't going to hold up, as they were given to me for eval purposes, and my goal was to destroy them on track. I was able to try out another set of the same pads at a different track, and knowing what their limitations were and being able to anticipate WHEN they give up the ghost, was able to manage it well enough to survive a whole track weekend.

Would *I* use the same pads on track again? Not if I want to have fun. Would YOU have any trouble with them? That is entirely up to you. Just judging from your description and use, I'd say no. But in this "sport" it is always better to have a margin for error, and *I* personally would swap either the factory GS pads back (they'll last longer and stop better than the Powerstop low dust pads for sure), or put in something along the lines of high performance street pads like a set of Hawk HPSes to make sure you have enough stopping power, if you don't want to deal with driving to and from the track with a set of squealing brakes the whole way.

Eventually though, if this is indeed what you'd like to do regularly, you're going to have to learn to swap pads regularly, as there is no such thing as track pads that work well on the street, or street pads that work well for the track.

2) Why does the owners manual have the following caution: Performing the brake burnish procedure on a "base" brake system can result in brake damage. Am I to assume that J56 is not a base brake system?

Someone else already said it. The burnishing procedure for Carbon Ceramic Matrix brakes are different than the burnishing procedure for the "base" brakes. CCM brakes require extreme heat generated to bond the pad material to the carbon ceramic compound. Iron rotors with pads just require 8-12 hard stops from highway speeds to nearly stopped to transfer a layer of pad material to the rotor. You do what you need to do for CCM brakes on a regular iron rotor based car, and it's likely to do some serious damage.

Plus CCM brakes are suppose to work at their best capacity when burnished, while iron rotors with basic pads SHOULD work at a pretty high capacity out of the box. They still need to be bedded in for best stopping power, but it's not like CCM brakes where once burnished they'll rip your eyes right out of your eye socket.

3) Did you guys with a GS/J56 brake system receive the additional brake hardware for track day events, i.e. cooling ducts, blocker rings etc? I did not with my 2019. Maybe I need to go back to the dealer and ask where my stuff is at??

I didn't. Ended up buying the ducts for $90.

4) I have the car lowered all the way down on stock bolts. Should I run them back up a bit in anticipation of the event, or any event in the future? Any clearance issues you guys are having with the car lowered all the way down (I'm running stock summer only tires).

This I can't answer for you. All I can say is, based on the tracks that are around me, low ground clearance isn't an issue.

Until I drove my lowered BMW at Laguna Seca.

Coming off of the famous cork screw, at the bottom of the hill, I heard a distinct "crunch!" and I knew either the front spitter or the rear diffuser was scraping against the ground, as the heavy change in elevation and full throttle has forced the rear to sit so damn low that the extended diffuser was scraping against the ground, once the decline has decreased to a more reasonable angle.

In that particular spot, I suspect even a full ride-height is going to cause the back to bottom out. So what I can tell you is, if you expect to take the car to the track more often? You're likely going to go to a specific track that ride height and ground clearance MIGHT be an issue. But even the best psychic won't be able to tell you for sure unless they drive the same car at the same track at the same speed as you're likely to achieve.

acroy

I don't drive it much as I should

2019GSTX

Thanks HACK...think I have enough good advice to set the car up correctly now and we'll see how it goes in July. A little trepidation of course but I'm sure once I'm out there it will go away quickly.

acroy….20 years in the Shady Shores, Corinth and Denton area and I can honestly say I haven't seen that car around....get that ride out! Honk if ya see me!

Poor-sha

My GS didn't come with the extra brake cooling ducts and I'm pretty sure those only come on the Z07 and the ZR1. I bought them separately but for what you're doing I wouldn't bother. It sounds like you've already decided but I would get some sort of dual track/street pad like the Ferodo DS2500 and put some Castrol SRF in for brake fluid.

Sellout

I've got nothing to add to this thread except this: Don't overfill the oil in a dry sump car. That old crap in the manual about adding 1/2 a quart of oil does not apply to a dry sump C7. All you'll get with that is oil all through the intake system.

X25

Actually, that half quart add-on suggestion is for the dry sump cars.

When 2014 models were initially released, the manual called for 10.5 quarts fill, identical to the C6 dry sump cars. But they held the release of the initial cars, and added a snippet to the user manuals, overwriting the suggestion back to 9.8 quarts, possibly due to foaming issues, etc. The manual now (instead) suggests getting back to that initial fill level only for track events.

Sellout

Ahh you're right, I just went back and re-read it. I'd be sure to remove that extra half quart before driving home. My dealership has overfilled mine by 1/2 a quart every time they've done the oil change, and it's always resulted in oil in the intake assembly on my street driven car.

Oh4GTO

How do the DS2500 compare to OEM pads?

Poor-sha

Feel is a lot like stock but they have a much higher heat range and don't melt on track like the stock pads. I am very hard on brakes and typically ran them as my street pad but I used them at VIR once when I ran out of DS 1.11 pads mid-event and was surprised at how well they held up.