Poor-sha

I originally posted this in the C7 Z06 section but I thought the folks in this section might find this interesting as well - particularly if they're thinking of tracking a C7 Z06. This was all HPDE and open track days so no racing or W2W.

I just wrapped up my last event of 2016 and thought I would do another recap of the year like I did last year.
https://www.corvetteforum.com/forums...rack-days.html

Here is my 2016 track season with my C7 Z06 by the numbers.

Track days: 26
Track Hours: 48.5
Laps: 1677
Track miles: 4431
Front pad sets used: 7
Rear pad sets used: 4
Front rotor sets used: 3
Rear rotor sets used: 1
Tires used: 32
Fuel consumed on track: 1067 gallons

I didn't include it in the numbers but I also did a two-day event in my F80 M3 and corded both front tires and ended up having to replace all 4 pads and rotors.

So far still no overheating with the C7Z even though I continue to get faster with this car. Below is a list of the issues I have experienced with the car.

1) Trans puking fluid out the breather. Finally GM discovered the cause was the anti-foaming agent in the fluid. My first trip to the dealer to flush the system helped but it needs to go back again as it's still doing it - just not as bad.

2) Service air bag light. This came on at my last event and I need to take to the dealer.

3) Exhaust leak and melted knock sensor harness. This happened to me once before and appears to have happened again. This ended my last event a half day early. Going to the dealer for this as well.

Other than that the car has been bullet-proof for me. Here are the stats for the life of the car (2015/2016 seasons).

Track days: 51
Track Hours: 102.5
Laps: 2574
Track miles: 9042
Front pad sets used: 12
Rear pad sets used: 8
Fuel consumed on track: 2255 gallons

Mordeth

Thanks as always for this information Poor-Sha. I am curious if you could comment on your opinion of your former C6Z track performance vs your C7Z. I know you ran a highly modified C6Z before getting the C7Z. Interested in your thoughts on the two cars ON THE TRACK. I own both cars but only want to run one on the track, so I started additional modifications to my C6Z (brakes, cooling, tires, tow hooks, shocks etc).

Great season. Simply amazing. 2500 laps!!!

Mark@AMT Motorsport

Good to hear of a car that's not over heating! What tracks and typical lap times do you see?

JeremyGSU

Wow. Great analysis and break down. 26 track days in one year is a ton IMO.

Sounds like it's been a great car.

Jay_Davis

I assume this is not a Z07, so we are talking about steel brakes and the standard Super-Sport tires.

I upgraded the rotors and pads in my Z51 to reduce the number of times I had to change them.

You do seems to go through tires pretty fast (every 6 hours). What tracks were you at?

Poor-sha

Non-Z07 car with the AP Racing endurance kit (CP9668 and 372mm rotors), GM secondary radiator, DSC Sport suspension controller, and the Tractive DDA shocks. I've tried a number of different pads but my go to continues to be the Ferodo DS 1.11.

As for tires, I broke this down in the original thread but here it is again.
- 4 sets of MPSC2 take-offs
- 1 set of A7s
- 1 set of R7s
- 2 sets of Pirelli scrubs

I spend most of my time at VIR and Summit Point but my best is a 1:59.2 at VIR Full and a 1:17.4 on Summit Main.

Poor-sha

I have to admit that on paper the C6Z had everything over the C7Z except in the aero department. My C6Z was ~500 lbs lighter, slightly more HP, had Moton double-adjustable coilovers, a Brembo BBK, real cage, containment seat, and a fire suppression system. It was a great track car.

I bought the C7Z as a street car and initially had no plans to track it more than once or twice. However, once I had the car on track I just fell in love with the way the car felt. It was just so easy to drive fast and I was far more comfortable pushing it than I was in the C6Z. Yes, it's heavier but it doesn't feel heavier on track and the massive low end torque propels the car out of corners with ease. The stock FE6 suspension was soft but with trail braking you get the car to rotate nicely. With the DSC Sport bits its just sublime and I feel like I can get the car to do whatever I want. The stock iron brakes worked fine with track pads but once I went to the AP Racing setup I started really abusing the brakes and I doubt the stock setup would hold me any longer.

I believe some of what made me more confident in the C7Z is the fact that the C7Z has some actual downforce whereas my C6Z had the ZR1 aero on it only. I also really like the fact that if something breaks I take it to the Chevy dealership and it usually doesn't cost me anything. In the end, I decided to sell the C6Z and started tracking the C7Z.

I'm sure the more experienced folks on this forum will think I'm crazy but if you already have both I would try them both out on track for a couple of events and then decide.

Mordeth

Thanks for the response and the comparison info. I am going to run both next year then, on consecutive days if I can.

TorontoC6

Poor Sha thanks very much for your insights on the C7. I very much appreciate reading your posts and have learned from them and they are one of the factors that influenced me to order a new C7 GS and plan to move from my current C6 race car to the new C7 GS (will run both next year then sell the race car).

I have been on these forums for a number of years and recently have been a little concerned by the craziness, lack of respect, and increasing hostility in the C7 section (e.g. C7 Z06 is the best car in the world..., all other cars are POS, poor people buy the GS cause they can't afford a Z06... etc. etc.). There are still a few individuals who are making a contribution to the forums rather than just boasting and battling, and you are one of them. Well done.

ZedO6

Excellent recap and wow...you are a track hoe! Can you in a future post outline the details on the car like options and upgrades, or point us to a previous post with this info?

Toilets

What were the symptoms you experienced when the knock sensor melted?

Poor-sha

The car would suddenly go very low on power. Often times it wouldn't rev over 4K RPM and it was like you only had 10% of the throttle to use. There was no CEL and the temps were fine. In fact, you could bring the car in and let it sit and go back out and would be slightly better. What I found was that if you just kept lapping it would eventually get a little better.

When the dealer pulled code they would see a knock sensor performance code. Eventually I started hearing the telltale "tick tick tick" of an exhaust leak and had the dealer check that - then they found the melted connector.

I had the same issue again this last trip to VIR and I had heard the ticking before I left but decided to go anyway. The car performed well until day 4 and then it would go in to that low power mode without CEL after a couple of laps.

This time the dealer didn't find a melted knock sensor but both cats were cracked and had to be replaced.

STANG KILLA SS

how are you tracking all that info, laps, miles, gallons, hours etc?

wouldnt mind to start doing the same.

Poor-sha

I have a spreadsheet that I log each event in. The number of laps is recorded by the Aim Solo DL and I just pull that from the test database after each event. Laps x track length = miles. I take an average lap time and multiply that by laps as well to get hours on track.

The C7Z typically can't make it through two sessions without running out of gas so I have to get fuel after every session. I know from experience that the car typically burns 11 gallons in a 30-minute session and also that the DIC typically shows an average of 3.9 MPG during a track event. So hours x 22 = gallons of fuel used at that event. Finally, my spreadsheet also has a column for which front pad, rear pad, and set of tires I was running.

I've been keeping this spreadsheet since I first started and keep adding columns as I realize there is some other bit of data I want to capture.

Poor-sha

The car is mostly stock with a few mods. It's a 2015 Z06 3LZ with the M7 trans. It is a non-Z07 car (FE6 suspension) and started life with the stage 1 aero. I added the stage 2 aero though before it ever went to the track.

Most of 2015 the car was run bone stock except the recommended 15W50 oil, Castrol SRF brake fluid, and Ferodo DS 1.11 pads. In the Fall of 2015 I added the AP Racing endurance brake kit as well as the stage 3 aero bits (rear center wicker and large splitter end plates).

Over the 2015-2016 Winter I added the GM Secondary Radiator and I drained the coolant in to a clean bucket and then added it back to the system plus some distilled water to get level right. I point this out because a lot of folks seem to feel you need to dilute the coolant mixture to keep the car cool but 2015 was 100% as it left Bowling Green and 2016 it was diluted some.

I also added the DSC Sport suspension control module and Tractive DDA shocks over that Winter and we modified the GM track alignment recommendations to change the rear caster from 0 degrees to 0.8 degrees laid back.

Finally, I bought and ran a couple of events this year with the Halltech Stinger RZ intake. I do believe the intake works as I was able to tie my previous best of a 1:59.2 at VIR on a 95F day with the intake and my top speeds on the back straight seem to be 2-3 MPH higher (it's tough to be consistent on this though). However, I removed it for my last 4 day event at VIR because of warranty concerns. As you've seen, my car has over 100 hours of track time on it which is a lot for any motor - especially one pushing 650 HP. I figure it's getting near end of life and I don't want any warranty hassles when it expires so I'm leaving he intake off for now.

Other than that I have lots of sets of wheels depending on which tires I'm running (Snow, MPSS, MPSC2, slicks).

Hope this helps.

Bill Dearborn

I imagine Poor Sha has been asked that question at least one hundred times. I feel like I have been asked it at least that many. He has summed up how I feel about the car Vs my pretty much stock C6Z. The car is just so much easier to drive and I am turning lap times at VIR I didn't think I would ever see. I really liked that C6Z but even though it is quite a bit lighter than my C7Z (weighed 3564 last weekend with a 3/4 full gas tank) it didn't have that low end torque the C7Z has. Other than the increase in the cost of consumables and the fact that it can't pass the gas pump at VIR it really is much better than my C6Z.

Bill

BEZ06

Well....it's good to know mine isn't the only car that gets <4 mpg!!!

I've only had it at two events so far (VIR and Daytona), and thought maybe my car was running way too rich or something because the fuel consumption just seemed really excessive.

My ZR1 gets 5.0 to 5.6 mpg at Daytona, and at Henry Gilbert's PDG event the beginning of Oct at Daytona it just seemed like the C7 Z06 should do about the same - but I was a little concerned that it was only getting 4 mpg or less.

Butt....it's good to know that I guess it's not a problem - just the normal fuel consumption for a C7 Z06!!!

I'll be running Daytona again Dec 9-11. They have 98 octane unleaded and 112 octane leaded gas available at the Speedway for around $9-$10/gallon, and I assume it's ethanol free.

I've got some Torco accelerator and plan to use that with 93 pump gas to raise the octane to 96-98 for the event, but I'll probably only get worse mpg!!

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