Corvette Z06 Forum banner

1 - 20 of 20 Posts

·
Registered
Joined
·
403 Posts
Discussion Starter · #1 ·
PREMISE: Just got back from three days of an intensive and grueling driving school located in Chandler, AZ – you guess which one. Learned a lot in a short time. Would recommend it to anyone who is serious about knowing and understanding the limits of their vehicle – and themselves. But what I found out about the Z06 platform from their technical crew was a revelation. Here are some of my observations about cars driven and beaten in the desert seven days a week. You decide.

OBSERVATIONS:

1) Z06 wheels: after over a year of continuous abuse, did not fail. Some bent rims occurred after hitting curbs and going on off road extrusions – BUT NO CATATROPHIC FAILURES. Lesson: save your money.
2) Brakes: rotors and calipers are so robust that big brake transformations are not needed. Drilled and/or slotted rotors are not used. Just lots of TLC on their maintenance. Lesson: save your money.
3) Brake pads: PFC metallics for the track. The Z-rated pads were tried and were found to wear too quickly. Hawk HP +’s are currently being used on their Grand AM’s that are drifting cars and are under review.
4) Brake fluid: DOT 5 SPF synthetic brake fluid is the way to go on the track – but it surely isn’t cheap - $85.00 a liter! Lesson: invest your money here.
5) Brake ducts: the often raved about Doug Rippie brake duct extensions are overkill. None of the C5’s or Z06’s run them in the desert heat. Lesson: put your bucks somewhere else.
6) Brake lines: stainless braided brake lines in hot, dry conditions build up such a static charge that they arc and interfere with the ABS system! Stay with fresh rubber hoses. Cheap investment here.
7) Oil capacities: 7 ¾ quarts of Mobil 1 for the motor.
8) Transmission/Differential coolers: these are a must for anyone doing hard driving on a track where there are lots of 2nd and 3rd gear changes. Temperatures without them cook the parts from 375 to 410 degrees! Use Mobil 1 fluids. Lesson: invest your money here.
9) Transmission/Differential cooler location: mount them behind the rear wheels venting out the rear fascia horizontal slots. Some cars have thermostats; some don’t. In the AZ summer, the coolers come on at ignition. To take advantage of this prime location requires the use of a central muffler on the X-pipe. Also, be sure to add a wide rubber mud flap to protect the fans and coolers from road junk kicked up by the tires. One comment from the technical crew was that the coolers were a whole lot quieter in this aft location, versus the Doug Rippie’s that are installed inside the rear fenders adjacent to the wheel ducting. (Even in a helmet with a loud exhaust I still heard the aft units whirring kick in.)
10) Radiator: bare bones stock. Don’t get suckered into buying an expensive after market unit! In fact, the school has run their cars with the consol temperature gauge pinned at 260 all day without one hick-up. While I would not do this myself, a GM engineer told them that this situation had been foreseen.
11) Clutches: Luk twin plates are used throughout, are beaten on daily, in the heat, and by some very ham-footed idiots. They’re a good investment, but make sure that you balance them before installation.
12) Suspension: bare bones stock, although I did see some plastic bushings on the sway bars – logical given the AZ heat.
13) Tires: Goodyear-sponsored Super Car F1’s.
14) Tire pressures: 40 pounds all around on the C5’s; 35 front and 28 rear on the Z06’s.
15) Platform reliability: When I asked several mechanics about “what breaks” on the Z06, I received blank stares. Finally, when prodded, worn tie rods were once mentioned, brake pads universally, and then silence. One just flat out said that the Z06 was over-engineered.
16) By the way, my two-year-old bright yellow anniversary C5 edition ride had 19,500 miles on it and it still ran like a deer.

CONCLUSION: We lucky individuals who own Z06's just don't know how good we have it!

DISCLAIMER: The purpose of this message is not to start an opinion firestorm about this and that. Rather, this is just what I saw and heard that I believed was worth sharing with you.

Grins. :coo:

PS: I still cannot wipe the grin off my face about the driving school.
 

·
Registered
Joined
·
2,459 Posts
FOXBAT said:
5) Brake ducts: the often raved about Doug Rippie brake duct extensions are overkill. None of the C5’s or Z06’s run them in the desert heat. Lesson: put your bucks somewhere else.

I have to take exception to this. I have turned my rotors blue, and boiled the fluid while autocrossing in the desert. High desert I might add, so high 90s, not the 110-115 of Phoenix.

This wasn't even pushing the car for more than 90secs at a time, and still I way overheated the brakes.
 

·
Premium Member
Joined
·
6,325 Posts
Thanks for the notes.
Another set of data points to help me set some priorities.
:ity:
 

·
Registered
Joined
·
1,383 Posts
Thanks for the report! :thumb:

However I must post some disagreements and a quick correction.

FOXBAT said:
4) Brake fluid: DOT 5 SPF synthetic brake fluid is the way to go on the track – but it surely isn’t cheap - $85.00 a liter! Lesson: invest your money here.
It's SRF and it's not DOT5, it's DOT4. Yes, its worth it, but it can be had for around $65/liter if you look hard enough. ;)

FOXBAT said:
5) Brake ducts: the often raved about Doug Rippie brake duct extensions are overkill. None of the C5’s or Z06’s run them in the desert heat. Lesson: put your bucks somewhere else.
I disagree. The DRM ducts + spindle ducts made a HUGE difference in the length of my sessions. Before them, I got pretty significant brake fade after 7-8 laps around Sebring. Now I can run for 45 minutes+ with no fade whatsoever.

FOXBAT said:
10) Radiator: bare bones stock. Don’t get suckered into buying an expensive after market unit! In fact, the school has run their cars with the consol temperature gauge pinned at 260 all day without one hick-up. While I would not do this myself, a GM engineer told them that this situation had been foreseen.
Before I installed my LG radiator/oil cooler, I saw oil temps in the 290-300 range on an 80* day at Sebring. Installed the LG unit and it runs in the 260 range now. I don't know how those cars ran at 260 all day on a stock radiator. :-? Must be the dry heat. :lol:

FOXBAT said:
CONCLUSION: We lucky individuals who own Z06's just don't know how good we have it!

PS: I still cannot wipe the grin off my face about the driving school.
:yeadog: :thumb: Glad you enjoyed it!!
 

·
Registered
Joined
·
1,388 Posts
I really enjoyed this post. Very informative. There's nothing like real-world experience to help point people in the right direction.

Thanks!

-Kirk
 

·
Premium Member
Joined
·
2,314 Posts
Look at ya. You're still grinning... ;)

Great read and glad you had fun!
 

·
Registered
Joined
·
579 Posts
Because I dont know... Can someone explain to me why they recommend:

"Tire pressures: 35 front and 28 rear on the Z06’s."

Seems funny to me.
 

·
Registered
Joined
·
3,166 Posts
Thanks for the heads up on Z06 durability and products used at this drining school.
 

·
Registered
Joined
·
236 Posts
Although I appreciate the observations, as all information is helpful - I don't agree with them as stated facts. There is a big difference between what is usable and what is a good solution. There are also huge differences in intended purpose.

Simply put a Z06 is a very great car as built for aggressive street driving, but that doesn’t mean the stock solutions are the best for competition driving. Just because a driving school uses a specific configuration, doesn’t mean it’s optimal.

In many cases a driving schools configuration is going to be based on BUSINESS requirements, not performance ones. Where they get their parts, what service agreements they have in place, and in many cases just general wear and tear.

Using stock tires would greatly reduce the “wear items” in a driving school, as the tires will last much longer then soft compound tires. They also don’t allow the car to brake as hard, which reduces brake pad/rotor wear.

All of this sacrifices performance, which is irrelevant for a driving school that is teaching technique. A given car configuration is dependant on the drivers and courses it is put on, not just the outside temperature.

MY OBSERVATIONS:

1) Z06 wheels: are generally great and handle a lot of abuse – right up until they fracture and you wipeout on the track. They will probably handle a medium-advanced driver for occasional use, or a medium driver for frequent hard use, but they still can fail. Overall they are excellent rims for a factory solution.
2) Brakes: rotors and calipers are fine for street use. I can eat up a complete set of stock rotors in 2 track days, so they aren’t exactly robust. They will fade very fast with race driving. The stock brakes CAN be easily upgraded internally with SS calipers, and will function very well for race use then with SS lines and a larger reservoir. A big brake package will show even less fade under very high race conditions.
3) Brakes Pads: Higher bite pads mean better times on a racecourse, but sacrifice wear on pads and rotors. An upgrade is a huge improvement for a race driver, but a driving school would care about costs over lap times.
4) Brake Fluid: SPF IS the best brake fluid of what I have used, although there are other decent fluids like Motuls that are much cheaper.
5) Brake Duct: Front brake duct extensions lower brake temps, which decrease fading and pad/rotor wear. They are a huge cheap improvement for people that are hard on their brakes.
6) Brake Lines: It’s easier to shield your ABS sensor then it is to take the added maintenance of rubber hoses, especially in hot climates. I have raced in AZ at 110+ temps and never had a static arc, but maybe I’m just lucky.
7) Oil: Mobil 1 or AMSOIL for me.
8) Transmission/Differential Coolers: Yes they are a must.
9) Transmission/Differential Coolers location: Anyplace that gets good cool airflow is fine. It’s not rocket science.
10) Radiator: I totally disagree with this one. Cooler engine temps equal longer lasting engines – period. Maybe if I swapped my car/engine out on a frequent basis like a driving school might I wouldn’t care, but I don’t have that luxury. My oversized radiator has a built-in oil cooler, which also is a critical component that wasn’t listed in this thread. I would consider a larger radiator a high need component for a race-prepped car.
11) Clutches: I have never used a Luk twin plate so I can’t comment, but I expect it depends on the engine HP. I use a McLeod Twin Disk personally, but my engine is nothing like stock. A good clutch designed to handle the current HP is always a good upgrade.
12) Suspension: Stock suspension is fine for minimal driving, it is also immeasurably cheaper to maintain. Again a driving school doesn’t care about performance, they need cost effective maintenance. A T1 suspension with Penske DA shock package with coil-overs is a huge, though costly upgrade.
13) Tires: Stock tires are fine for low cost aggressive driving in hot dry climates. They are nothing compared to a soft compound DoT approved tire, which are nothing compared to a true R-compound race tire. If your primary need is high mileage (low cost) then F1’s are great, but for real racing (or a high HP modded car) you NEED a soft compound tire.
14) Tire pressures: If I ran 40 lbs pressure on my tires cold they would burst when they heated up. I also don’t like that much front to rear difference, but that’s just personally taste. I run 31F/29R cold.
15) Platform reliability: A stock Z06 is very robust with decent maintenance. When you modify them it can be a different story. Still an awesome platform!

CONCLUSION: The needs for a business do not translate to the needs of an individual. A driving school is going to maintain their cars to a different set of standards then a race driver or a casual owner. It really depends on what you are doing with the car as to what you need.

DISCLAIMER: These are just MY opinions from my experiences; no statement of fact is intended.

Cheers! :cheers:
 

·
Registered
Joined
·
403 Posts
Discussion Starter · #14 ·
Technical Lessons Learned Commentary

I wish to thank all those veterans out there for all their fine comments, based on hard-earned track wisdom, and kind observations to my initial post. This is what forums are all about.

However, regarding the sheer abuse that the Z06 platform undergoes at a high performance driving school, on a nearly daily schedule, I still am amazed at the machine and the punishment that it can take.

Seriously, how many Z06 owners would put their own investment under such daily, continuous stress and strain - even on track day?

Further, whether one can say that a performance school's vehicles can or cannot be compared to a fully decked out race car was not the thrust of my post. Rather, rarely can we see, experience, or measure in a qualitative fashion what the durability of our cars is and just how much they can take. Why? Because we just love 'em just so much.

So, in a given closed environment, nearly round the clock, I reported that our platforms are withstanding terrific punishment and still they perform most admirably.
 

·
Registered
Joined
·
5,563 Posts
I appreciate your post and understand you made it to share info with all the forum members. But, I agree with Nocturne that a school is profit driven and much of what they use, or do, is based on that. So, in my opinion, what they do or use doesn't mean it is the best overall solution.

But, I have over two and a half years of racing my car in the SCCA T1 in the Midwest heat and I disagree with or have had other experiences in several cases. So, not meaning to contradict you, but just to share another opinion for others to ponder, here are my thoughts and experiences:

1) Z06 wheels: after over a year of continuous abuse, did not fail. Some bent rims occurred after hitting curbs and going on off road extrusions – BUT NO CATATROPHIC FAILURES. Lesson: save your money.
I've read several posts on various Corvette forums of stock wheels failing at speed. While I think the stock wheel is relatively safe, I also don't think it is the only, or even the best solution. In my opinion, a set of dedicated track wheels from someone like CCW or Kodiak is a good investment.

2) Brakes: rotors and calipers are so robust that big brake transformations are not needed. Drilled and/or slotted rotors are not used. Just lots of TLC on their maintenance. Lesson: save your money.
Agree somewhat. I can run a 45 minute SCCA T1 race and still activate ABS on the last lap, implying I am limited by grip (and I run R compound tires) vice braking power. But... I have DRM ducts, run Carbotech race pads (XP11 front, XP10 rear is my current pad), use Goodridge SS lines with AN fittings and run Wilwood EXP 600 Plus fluid.

With this setup, my rotors and pads last maybe three track weekends, or about 12 track sessions. My calipers only last about 8-10 track weekends before the rubber boots are gone and the calipers have spread. Calipers are on my annual replacement list.

3) Brake pads: PFC metallics for the track. The Z-rated pads were tried and were found to wear too quickly. Hawk HP +’s are currently being used on their Grand AM’s that are drifting cars and are under review.
PFC metallic pads are costly and the dust is nasty for the wheels. Carbotech pads are much less, work better in my opinion and the dust isn't metallic and doesn't rust.

4) Brake fluid: DOT 5 SPF synthetic brake fluid is the way to go on the track – but it surely isn’t cheap - $85.00 a liter! Lesson: invest your money here.
SRF is the standard, but as you say is very costly. I use Wilwood EXP 600 Plus (or Motul RBF 600) both of which are very good and much less than SRF. I probably only use about six bottles of brake fluid in a whole season and I bleed my brakes all the time. Not really cost effective for me to use the SRF given the price difference.

5) Brake ducts: the often raved about Doug Rippie brake duct extensions are overkill. None of the C5’s or Z06’s run them in the desert heat. Lesson: put your bucks somewhere else.
Every SCCA T1 car I've seen has DRM brake ducts. They lower rotor and pad temp. I noticed improved brake feel and longer pad and rotor life when I installed them. Are they absolutely required? Probably not. Are they worth $200? In my opinion, yes.

6) Brake lines: stainless braided brake lines in hot, dry conditions build up such a static charge that they arc and interfere with the ABS system! Stay with fresh rubber hoses. Cheap investment here.
Rubber lines are susceptable to damage and failure on the track. I've run Goodridge SS lines for over three years now with no problems. Static charge isn't an issue with Goodridge SS lines.

7) Oil capacities: 7 ¾ quarts of Mobil 1 for the motor.
I'm betting they are receiving sponsorship from Mobil 1. Mobil 1 is a good oil, but it isn't necessarily the best.
Comparative Oil Test
AMSOIL vs Mobile 1 Oil Test

8) Transmission/Differential coolers: these are a must for anyone doing hard driving on a track where there are lots of 2nd and 3rd gear changes. Temperatures without them cook the parts from 375 to 410 degrees! Use Mobil 1 fluids. Lesson: invest your money here.
Agree that coolers can be important, especially in hot temps. Ditto my above comment that Mobil 1 isn't the only game in town.
AMSOIL ATF
AMSOIL Severe Gear Extreme Pressure Synthetic 75w90

10) Radiator: bare bones stock. Don’t get suckered into buying an expensive after market unit! In fact, the school has run their cars with the consol temperature gauge pinned at 260 all day without one hick-up. While I would not do this myself, a GM engineer told them that this situation had been foreseen.
Try a dyno run at 260 degrees. The car goes into auto protection mode at something like 265 degrees coolant temp. I run a DRM aluminum radiator and in 100 degree heat in full race conditions my coolant temp stays at about 200 degrees. In my opinion, the money spent on this radiator was well worth it.

15) Platform reliability: When I asked several mechanics about “what breaks” on the Z06, I received blank stares. Finally, when prodded, worn tie rods were once mentioned, brake pads universally, and then silence. One just flat out said that the Z06 was over-engineered.
My personal experiences:
- Seized a bearing destroying my motor in July 2003 (running Mobil 1 15w50)
http://www.z06vette.com/forums/showthread.php?t=41691
- Broke a timing chain in April 2004
http://www.z06vette.com/forums/showthread.php?t=61443
- Had a harmonic balancer come off destroying my 2nd motor in Sept 2004
http://www.z06vette.com/forums/showthread.php?t=68418

I've also replaced the clutch due to wanting to prevent the dreaded clutch sticking to the floor at the wrong time.

Don't get me wrong, I wouldn't be racing a Z06 if I didn't love it. The car is a great car, but it does have some minor reliability issues that should be considered prior to tracking it, or modifying the engine as my above posts indicate.
:cheers:
 

·
Registered
Joined
·
299 Posts
I see you mentioned the coolers for the trans and dif were placed in the rear where the mufflers use to live. Not the best place even with the air flow that is there. In competition if some one were to tag you there you would be done even with a lite tap and that does happen. Get them away from the outter corners of the car. My 2 cents worth.
Tony #54
 

·
Registered
Joined
·
17,744 Posts
WOW! lots of Great info here. :ity:

.
 

·
Registered
Joined
·
520 Posts
Over-engineered?!?!!?

I guess I don't need to mention shift forks then. I agree that the engine is rock solid, but they left the transmission out of that equation.
 

·
Registered
Joined
·
844 Posts
I agree completely with FOXBAT. I was given a driving school (big name) at Moroso Raceway when I purchased my Z. Although a private company, these cars were owned by GM and they used the stock clutches and brakes and had the same experience--rarely does something break--and we hammered the cars. They also said the Z is over engineered. Likewise I also agree with comments with you guys who campaign your cars that there are areas that need some extra support. Overall, we have GREAT CARS!!!!!!!!!!! :thumb:
 

·
Registered
Joined
·
752 Posts
This is one of the better threads I have read. Guess I don't see much disagreement...just different levels of recommendations and experiences based on the level and intensity of the racing.

No doubt the Z is a marvelous vehicle for street use and ocassional competion (great platform for driving schools). Also apparent that the Z can be even more competive when modified properly and when every bit of performance is needed / expected.

Hope to some day take a good driving school so I can have some seat experience and learn what my Z can really do. I really envy the experience and skills you guys are developing.

Thanks for sharing your knowlege! :jammin:
Keep it up and let us dreamers learn from your experience.
 
1 - 20 of 20 Posts
Top