What Would Be Your Ultimate C7 Track Car Build?
12-07-2018, 04:44 PM
#81
Le Mans Master
With regard to a cage- read the fine print. I think I recall my extended warranty specifically calling out a cage. I have a garage at the track where my dedicated track car(s) live. The C7 is for the tracks I go to on member days and on other people's membership so it doesn't get nearly as much track time. I'm not going to cage it. The other cars are caged though.
12-07-2018, 09:47 PM
#82
Le Mans Master
I don't disagree with you and that's how I've operated the last 4 years. However, it also means that if you find a weak spot in the car for heavy track use your hands are tied for being able to mod the car to address it. It also is dependent on having a quality dealer tech nearby that knows what they are doing. Unfortunately, the excellent tech I worked with for most of that period moved away and I've been unable to find someone anywhere near as competent. If I'm going to reduce consumable costs I need to shed weight and that means heavy modifications. My hope is that by working with the best aftermarket companies I can build something that is reliable and that after all these years with the C7 family I have the knowledge and tools to support it.
643lb-ft on the ZR1? Typo?
12-08-2018, 04:10 PM
#83
Premium Supporting Vendor
Nope. Right on par with this article as far as torque, hp was a little higher because we dyno'ed a manual that had half 93 octane half MS109 in the tank. https://jalopnik.com/the-first-new-z...e-w-1824243496
12-08-2018, 10:35 PM
#84
Instructor
I would suggest going with a GS lightened with race seats and harnesses. Add the appropriate suspension pieces, AP racing brakes, and your wheel/tire setup for track use. For HP over the stock 6.2, go supercharger only and leave the internals stock. Higher lift cams are great for a "cruise-in" putt around car but seem to cause issues after hard track miles. There are exceptions but an Edelbrock, Magnuson, or Whipple system will get you in a nice HP range with no other supporting mods. Use the associated company's canned tune and get their warranty which includes engine replacement. This setup should be as fast or faster than a Z06. At VIR Full course, a stock GS with slicks can run 2:05-2:06 so the mods mentioned should get you in the range where you like to run...(2:00 & under). Have fun and I'm sorry about the ZR1. I met you at VIR during Audi Club after you had the exhaust issue. I have the black 2017 ZL1.
12-09-2018, 08:58 AM
#85
Safety Car
Member Since: Sep 2014
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There was actually a guy doing 2 minute flat times in a GS earlier in the year. I think Sean had some of his pdr vids, overlayed them on pi workshop with his own, and had a youtube video showing the differences in speeds on the straights and corners.
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Stephen02Z06 (12-09-2018)
12-09-2018, 10:42 AM
#86
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range96 (12-09-2018)
12-09-2018, 12:25 PM
#88
Yeah, @Koan is the quickest I've seen at VIR in a GS on slicks and he sent me data for a 2:01.66. The head to head and data comparison videos are on my YouTube channel.
https://www.youtube.com/watch?v=3jWN9mEa-eQ
https://www.youtube.com/watch?v=4nVb5n9mCRU
https://www.youtube.com/watch?v=3jWN9mEa-eQ
https://www.youtube.com/watch?v=4nVb5n9mCRU
Last edited by BrunoTheMellow; 12-09-2018 at 12:27 PM.
12-09-2018, 01:24 PM
#89
Safety Car
Member Since: Sep 2014
Location: in the country North Carolina
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Yeah, @Koan is the quickest I've seen at VIR in a GS on slicks and he sent me data for a 2:01.66. The head to head and data comparison videos are on my YouTube channel.
https://www.youtube.com/watch?v=3jWN9mEa-eQ
https://www.youtube.com/watch?v=4nVb5n9mCRU
https://www.youtube.com/watch?v=3jWN9mEa-eQ
https://www.youtube.com/watch?v=4nVb5n9mCRU
12-09-2018, 01:32 PM
#90
Track Rat
Thread Starter
I knew he was really fast in a GS. I guess he got faster in my memory. I'm trying to decide whether to keep the z06 or move into a different c7. I still have warranty until March of 20 so I'm probably going to run next year on the z06 unless something changes my mind. Too many spares, etc to go in a different direction.
Last edited by Poor-sha; 12-09-2018 at 01:33 PM.
12-09-2018, 01:53 PM
#91
Drifting
C7 Base, AP Brakes, LG suspension, 427 shortblock, port heads, big cam, ported MSD, and 18x11/12.5's once you piece together a cheap widebody from wrecked or aftermarket suppliers. This is probably the cheapest route.
A GS would be $55k, Katech 427 $20-$25K, and for $50k or less you can do mentioned above.
A GS would be $55k, Katech 427 $20-$25K, and for $50k or less you can do mentioned above.
12-09-2018, 03:37 PM
#93
Advanced
What’s gonna happen to the used Pratt race cars? Can those be bought? What about a car like lou’s Ring car? Not to reopen the fi/na question, but you’ve got a lot of headroom to add power if need be w an fi car, that the 427 wouldn’t?. Eventually, adding a little more power is a lot cheaper than adding a bit more lightness, at least on what originates as a street car. Eventually, you don’t want a c7 you want a lotus, or you don’t want a c7, you want a viper, either smaller everything or bigger everything.
A question on the cages, it looks a bit like some of those cages are falling into the nascar trap- every time there was a new wreck, they would add another bar. They got so rigid, they became less safe, transmitting deceleration loads to the driver rather than coming apart and shedding energy on impacts. There’s substantial question whether or not a car that was originally designed w crumple zones, airbags and standard belts is safer when those systems are removed, then replaced w a rigid cage. There’s a basic difference how they deal w a given impact. If you look at rally cars, they have passive foam restraints built into the car that act like a motorcycle helmet, a rigid shell, and the delicate contents deforms the foam on impact. Those cages are tied all the way to the suspension attachment points if memory serves, then the body panels are figured out later. The benefit of a race car vs a street car. It takes a lot to carefully develop an integrated safety system vs “ putting in a cage that fits” that’s a compromise because it’s not a race car. That’s not a comment meant to denigrate what looks like a well built cage, but a question about the plan. And regarding aluminum cages, I’m not sure that they meet any fia spec, I think it’s only t45 and cds. But that may be old info.
All that said, what a great project.
And my underinformed, under experienced useless opinion on the nannies is that if you are triggering them then you can improve how you are driving the car, no? Perfect driving according to all the sensed input would result in no nanny input, right? They are helpful to almost all because they modulate many things in fractions of seconds that there are not controls for, nor could any driver keep track of. But it’s a public forum, so I’m sure I’ll be told how wrong that statement is shortly.
A question on the cages, it looks a bit like some of those cages are falling into the nascar trap- every time there was a new wreck, they would add another bar. They got so rigid, they became less safe, transmitting deceleration loads to the driver rather than coming apart and shedding energy on impacts. There’s substantial question whether or not a car that was originally designed w crumple zones, airbags and standard belts is safer when those systems are removed, then replaced w a rigid cage. There’s a basic difference how they deal w a given impact. If you look at rally cars, they have passive foam restraints built into the car that act like a motorcycle helmet, a rigid shell, and the delicate contents deforms the foam on impact. Those cages are tied all the way to the suspension attachment points if memory serves, then the body panels are figured out later. The benefit of a race car vs a street car. It takes a lot to carefully develop an integrated safety system vs “ putting in a cage that fits” that’s a compromise because it’s not a race car. That’s not a comment meant to denigrate what looks like a well built cage, but a question about the plan. And regarding aluminum cages, I’m not sure that they meet any fia spec, I think it’s only t45 and cds. But that may be old info.
All that said, what a great project.
And my underinformed, under experienced useless opinion on the nannies is that if you are triggering them then you can improve how you are driving the car, no? Perfect driving according to all the sensed input would result in no nanny input, right? They are helpful to almost all because they modulate many things in fractions of seconds that there are not controls for, nor could any driver keep track of. But it’s a public forum, so I’m sure I’ll be told how wrong that statement is shortly.
12-09-2018, 03:55 PM
#94
Drifting
Member Since: Jun 2016
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2020 Corvette of the Year Finalist (track prepared)
C7 of Year Winner (track prepared) 2019
What’s gonna happen to the used Pratt race cars? Can those be bought? What about a car like lou’s Ring car? Not to reopen the fi/na question, but you’ve got a lot of headroom to add power if need be w an fi car, that the 427 wouldn’t?. Eventually, adding a little more power is a lot cheaper than adding a bit more lightness, at least on what originates as a street car. Eventually, you don’t want a c7 you want a lotus, or you don’t want a c7, you want a viper, either smaller everything or bigger everything.
A question on the cages, it looks a bit like some of those cages are falling into the nascar trap- every time there was a new wreck, they would add another bar. They got so rigid, they became less safe, transmitting deceleration loads to the driver rather than coming apart and shedding energy on impacts. There’s substantial question whether or not a car that was originally designed w crumple zones, airbags and standard belts is safer when those systems are removed, then replaced w a rigid cage. There’s a basic difference how they deal w a given impact. If you look at rally cars, they have passive foam restraints built into the car that act like a motorcycle helmet, a rigid shell, and the delicate contents deforms the foam on impact. Those cages are tied all the way to the suspension attachment points if memory serves, then the body panels are figured out later. The benefit of a race car vs a street car. It takes a lot to carefully develop an integrated safety system vs “ putting in a cage that fits” that’s a compromise because it’s not a race car. That’s not a comment meant to denigrate what looks like a well built cage, but a question about the plan. And regarding aluminum cages, I’m not sure that they meet any fia spec, I think it’s only t45 and cds. But that may be old info.
All that said, what a great project.
And my underinformed, under experienced useless opinion on the nannies is that if you are triggering them then you can improve how you are driving the car, no? Perfect driving according to all the sensed input would result in no nanny input, right? They are helpful to almost all because they modulate many things in fractions of seconds that there are not controls for, nor could any driver keep track of. But it’s a public forum, so I’m sure I’ll be told how wrong that statement is shortly.
A question on the cages, it looks a bit like some of those cages are falling into the nascar trap- every time there was a new wreck, they would add another bar. They got so rigid, they became less safe, transmitting deceleration loads to the driver rather than coming apart and shedding energy on impacts. There’s substantial question whether or not a car that was originally designed w crumple zones, airbags and standard belts is safer when those systems are removed, then replaced w a rigid cage. There’s a basic difference how they deal w a given impact. If you look at rally cars, they have passive foam restraints built into the car that act like a motorcycle helmet, a rigid shell, and the delicate contents deforms the foam on impact. Those cages are tied all the way to the suspension attachment points if memory serves, then the body panels are figured out later. The benefit of a race car vs a street car. It takes a lot to carefully develop an integrated safety system vs “ putting in a cage that fits” that’s a compromise because it’s not a race car. That’s not a comment meant to denigrate what looks like a well built cage, but a question about the plan. And regarding aluminum cages, I’m not sure that they meet any fia spec, I think it’s only t45 and cds. But that may be old info.
All that said, what a great project.
And my underinformed, under experienced useless opinion on the nannies is that if you are triggering them then you can improve how you are driving the car, no? Perfect driving according to all the sensed input would result in no nanny input, right? They are helpful to almost all because they modulate many things in fractions of seconds that there are not controls for, nor could any driver keep track of. But it’s a public forum, so I’m sure I’ll be told how wrong that statement is shortly.
If the nannies are on and you're not triggering them you're not going to be driving anywhere near the limit.
Sport 1 Active handling remains on as well as TC.
To be "fast' the car in many scenarios has to rotate. If the nannies aren't allowing rotation. you're not gonna be fast. If you cant get power down because it's cutting throttle on corner exit you're not going to be fast.
Nannies teach that it's okay to just smash the throttle like an on/off switch with no side effects. Turn the nannies off and do that and you'll loop the car.
As far as cages are concerned, safety is a series of things.
airbags shouldn't be in a car with harnesses, cage etc.
and a cage shouldn't be in car without harnesses.
same thing with a HANS or other head and neck restraint.
there is literally a single sheet of fiberglass between me and the outside world without a cage.
Cages and their safety in street cars has been demonstrated on track many many times.
Cage design has less to do with the fabricator and more to the rule set of a given organization. Many of those organizations adhere adopt a similar set of rules regarding cages from FIA.
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village idiot (12-09-2018)
12-09-2018, 05:40 PM
#95
Burning Brakes
I love the platform and want something I can beat on heavily doing DEs, track days, and TT. Of course it needs to be fast and reliable but it should be as light as possible to reduce consumable costs. I don't want to make any compromises for street use as this will be a 100% track car
Yup, I'm just getting opinions and seeing what I might've missed or should reconsider. Here's a partial list:
- 2019 GS 1LT with Performance Data Recorder ('cause I need my data)
- Cage, seats, harnesses, gutted interior to include removing the side windows. I'm fortunate to have Piper Motorsports just up the road from me and they build great cages
- AP Racing brakes
- DSC Sport controller and Tractive DDA RTx shocks. I really loved this setup on my Z06.
- I'm talking to Jason at Katech about a build including their awesome 427 LT1.
- this car will be NA and won't have an A/C condenser (better airflow to the radiator).
Unfortunately, something has come up and I won't be tracking the ZR1 any more and I really have no need to have my track car be a street car any more.
- I took advantage of the Black Friday sale to also order a set of AMT spherical bushings.
- If I'm going to reduce consumable costs I need to shed weight and that means heavy modifications. My hope is that by working with the best aftermarket companies I can build something that is reliable and that after all these years with the C7 family I have the knowledge and tools to support it.
Yup, I'm just getting opinions and seeing what I might've missed or should reconsider. Here's a partial list:
- 2019 GS 1LT with Performance Data Recorder ('cause I need my data)
- Cage, seats, harnesses, gutted interior to include removing the side windows. I'm fortunate to have Piper Motorsports just up the road from me and they build great cages
- AP Racing brakes
- DSC Sport controller and Tractive DDA RTx shocks. I really loved this setup on my Z06.
- I'm talking to Jason at Katech about a build including their awesome 427 LT1.
- this car will be NA and won't have an A/C condenser (better airflow to the radiator).
Unfortunately, something has come up and I won't be tracking the ZR1 any more and I really have no need to have my track car be a street car any more.
- I took advantage of the Black Friday sale to also order a set of AMT spherical bushings.
- If I'm going to reduce consumable costs I need to shed weight and that means heavy modifications. My hope is that by working with the best aftermarket companies I can build something that is reliable and that after all these years with the C7 family I have the knowledge and tools to support it.
I tried to capture the things you have already settled on and I agree with all of them. I even see the logic of building the C7 GS although it is somewhat at odds with the most recurrent stated objective which is "to reduce weight in an effort to reduce consumables" This car is starting out heavier than I would like but this is somewhat forgivable and offset by the robust traction management system and data collection capability. Also, the DSC shock system is already adapted to the C7 with no solution yet for the C5 or C6 cars. I am incorporating many of the suggestions of others that are consistent with what I would do and then adding my personal touches in order of importance.
The build:
Base Car: C7 GS M7 1LT, Torch Red (Not sure if you need to get Z07 option pkg to add DSC controller and shocks?)
Safety:
- Race cage
- Race seats
- AMT Ultralow seat mounts
- Racing harness system
- HANS head and neck restraint
- Fire suppression system
- Tow Hooks
- rear camera system
Weight Reduction:
- Remove AC
- Remove OEM interior and sound deadening material
- Remove side glass
- Replace rear hatch glass with Lexan (Maybe install Katech CF rear hatch)
- light weight battery
- CF body panels where applicable
- Light weight race seats
- Leight weight 18" wheels. I would get the Finspeed F110 18x11 FR, 18x13 RR with knurled bead seat, RT, and Ultralite options. Satin Charcoal finish.
- As noted above Essex/AP Racing Radical CP9668/372mm Front and CP9450/365mm Rear (I don't think the GS needs the 390mm disk)
- I would take every bit of weight possible off the front of the car including the headlights if you can get away with it.
- Aftermarket exhaust system (this will also fall under power) This is a big target of opportunity for dumping weight.
- GM performance carbon fiber driveshaft and torque tube (if not already so equipped). GM says this is good for losing 15.5 lbs. There is a heat shield that goes with this kit.
- GM performance carbon fiber chassis braces
- Lighter clutch and flywheel when the engine gets upgraded (more detail under power upgrades)
Chassis:
- LG G7 Swaybars
- LG C7 Drop Spindles
- AMT Monoball A-arms
- AMT Camber Kit
- DSC Controller and Tractive DDA RTx shocks. I saw this system at PRI last year and I think this is the future of suspension. Also met Randy Pobst at the booth!
- GSpeed Corvette Extended Wheel Studs & Lug Nuts
- Granatelli Toe Link Kit
- LGM spindle duct kit.
- Your favorite track tires
- 50/50 to 48/52 F to R weight balance (you need to be careful about losing too much weight in the rear of the car vs the front.) I would mount a 10 lb fire retardant bottle in the rear end of the car and don't go crazy with the lightest battery you can find.
- Corner balancing and optimized track alignment
Body and Aero:
- LG Motorsports Carbon C7 Challenge Hood
- GSpeed front splitter and LG C7 GT2 Wing. If you can harvest the wing of the ZR1 I would use that.
- I don't know if it would work, but I I would love to put the ZR1 nose and fenders in the GS. That is one mean looking front end, it may involve too much cost and effort.
- The drop spindles will lower you 1"
- Does anyone make an effective rear diffuser? Not a fan of the Kateck solution.
- I would work very hard at smoothing up the bottom of the car paying attention to the efforts of Ferrari and a few guys that have really developed the underbody aero of the corvettes. In fact, I would work on this and a real diffuser before adding the wing.
More Power & Driveline:
- 427 to 440 ci LT1. You have to sleeve the block to do this and I don't see why you can't go with a 4.185 bore and 4.0 inch stroke for 440 ci. The easiest and most reliable way to add torque and power is with displacement. You could port the OEM heads but I would look hard at the Edelbrock Victor Jr. LT1 heads with copper alloy seats which will allow you to run Ti valves with higher reliability. With large displacement, you really don't need to go with an aggressive valve lift to make power where you want it. Since this is a track only car I would favor duration over very high lift, stay with OEM rockers and light valves and springs for RPM headroom. Use a Mamo ported MSD intake and 103mm throttle body with Halltech CAI. ARE 2.0" long tube headers, catless mid pipes, and Burns 4.5" mufflers. I would bite the bullet and do a real dry sump system, ARE or Dailey Engineering. I could go into extreme detail on how I would execute this engine build, but suffice it to say, 650-700 reliable crank horsepower is not very hard to acheive.
- I would send the gearbox and diff to RPM for some upgrades and REM treatment. I haven't done an analysis on the TR6070 gearing, but you should give this some thought to determine how the ratios and shift points will work with your driving style and favored tracks.
- I would talk to LGM and GSpeed about engine and driveline cooling upgrades for this setup. I think they have worked harder on these issues than anyone else in the business and will offer intelligent solutions.
- MGW Shifter
I'll leave it here for now. It's been a fun little bench racing exercise on a snowy afternoon. If I were in your shoes I would do all the safety, chassis, aero, and weight reduction for the first track season before messing with the engine. Spend an entire season seeing how far you can take the GS with these modifications. I would bet you can get scary close to your best time in the ZR1, and then you can better assess how crazy you want to go with the engine. Big displacement and low stress = higher reliability and the cooling systems can be vastly simpler than a power adder solution. A real race engine will also be costly and you can split this build up over a couple of years and reduce the risk of cutting into your track season if there are delays, and there always are.
My 2¢
Scott
Last edited by Bad_AX; 12-09-2018 at 06:48 PM.
12-09-2018, 05:46 PM
#96
Advanced
If the nannies are on and you're not triggering them you're not going to be driving anywhere near the limit.
Sport 1 Active handling remains on as well as TC.
To be "fast' the car in many scenarios has to rotate. If the nannies aren't allowing rotation. you're not gonna be fast. If you cant get power down because it's cutting throttle on corner exit you're not going to be fast.
Nannies teach that it's okay to just smash the throttle like an on/off switch with no side effects. Turn the nannies off and do that and you'll loop the car.
As far as cages are concerned, safety is a series of things.
airbags shouldn't be in a car with harnesses, cage etc.
and a cage shouldn't be in car without harnesses.
same thing with a HANS or other head and neck restraint.
there is literally a single sheet of fiberglass between me and the outside world without a cage.
Cages and their safety in street cars has been demonstrated on track many many times.
Cage design has less to do with the fabricator and more to the rule set of a given organization. Many of those organizations adhere adopt a similar set of rules regarding cages from FIA.
Sport 1 Active handling remains on as well as TC.
To be "fast' the car in many scenarios has to rotate. If the nannies aren't allowing rotation. you're not gonna be fast. If you cant get power down because it's cutting throttle on corner exit you're not going to be fast.
Nannies teach that it's okay to just smash the throttle like an on/off switch with no side effects. Turn the nannies off and do that and you'll loop the car.
As far as cages are concerned, safety is a series of things.
airbags shouldn't be in a car with harnesses, cage etc.
and a cage shouldn't be in car without harnesses.
same thing with a HANS or other head and neck restraint.
there is literally a single sheet of fiberglass between me and the outside world without a cage.
Cages and their safety in street cars has been demonstrated on track many many times.
Cage design has less to do with the fabricator and more to the rule set of a given organization. Many of those organizations adhere adopt a similar set of rules regarding cages from FIA.
on the nanny front, and there plenty of info on this, if you are past the limit, as the settings you chose and the program dictates from the sensor data present, the nannies intervene- that said, if you are on the bleeding edge limit, hypothetically, you would be as fast as is possible, and the nannies wouldn’t intervene, as you are at the limit, not exceeding the programmed envelope. The various settings allow a larger envelope, more yaw (rotation), more tire slip, more power to be put down. I hope we agree on that? If not, well, I dunno. The learning curve is difficult to test for most drivers, who pay for their hardware, and are not Randy pobst or a development driver, especially in a car that can pull a g on a skid pad and has 650hp. It takes a long time on a track to find the limit. The nannies just keep you from paying for making SOME mistakes. Will they slow hamhanded roughshod drivers (DO NOT TAKE OFFENSE NOT INTENDED TO MEAN YOU) downsometimes? Probably, because they aren’t listening to what the car is telling them. will some drivers be faster without them? Of course. But even the fastest guys seem to do a bit better w the systems developed at Ferrari, Porsche and I think in the c7 case. Ymmv, tho. And we agreed they do reward bad habits and make you look better than you are. The designers and engineers did that on purpose, they will tell you, allowing you to safely “access” more of the cars potential ����*♂️
regarding safety systems, I think we agree. I was stating that a system has to be developed, not pieces interchanged between different philosophies. Open wheel cars have a life cell, and the cars are designed to disintegrate, dissipating as much energy as possible, over the longest duration possible( in milliseconds). That is in distinction to old thinking, which was “keep making the car stronger, more rigid, to tolerate high impact loads, and the driver will be safer”. It’s dissipation of energy, not rigidity, and both come into play. NASCAR changed that thinking when DE lost his life and the COT was introduced. Open wheel was ahead of them. This was around the time of the introduction of the HANS device.
cage design is a combination of specifications from a sanctioning body, who says you have to have these bars, made of these materials connecting this. The role of the fabricator is huge. To have a truly certified cage, I believe a manufacturer must submit sample welds as well as meet the specs.
Regarding cage safety of street cars on tracks, well I agree, there’s lots of “examples”. That’s different than controlled crash testing. No crash is controlled, street or track. You can’t predict the severity, vector, etc. But you must follow certain ideas, as we both outlined. And without careful measurement of impact loads to the occupant, there is no way to say which is better in a given scenario. I would add that the engineers at the race car manufacturers and street car manufacturers take great pains to maximize safety. I’ve seen it firsthand, and the development over time. Modern race car construction allowed an occupant to sustain a 193g hit and survive. Old school rigid cage systems pre HANS never achieved 100g I believe. A harness bar that’s lower than your helmet and 4 points is not a carefully developed system. My point is simple, and not derogatory to anyone, have a plan for your safety system, use quality material, tested ideas, engineered and fabricated well. And try not to crash. That helps, too.
A helmet is just a thin sheet of composite and foam, so is the head surround ( not the halo) in F1 and its amazing how well those work. Nothing will stop the catch fence from intruding into the life cell or cage of any car if the impact is great enough, at the weak point of a system, etc. be safe out there, it’s brutal when sh*t goes wrong.
see attached https://www.racing-reference.info/showblog?id=3018
http://www.formula1-dictionary.net/g_force.html
not trying to argue. Just trying to add what I think are facts to the discussion. If I’m wrong, I apologize.
Last edited by Plstxmd; 12-09-2018 at 06:01 PM. Reason: Added second reference
12-09-2018, 06:17 PM
#97
Drifting
Member Since: Jun 2016
Posts: 1,266
Received 310 Likes
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213 Posts
2020 Corvette of the Year Finalist (track prepared)
C7 of Year Winner (track prepared) 2019
oh yah we agree and was just providing my own opinion didn't mean to look like i was arguing.
The nannies, up until "Race" in PTM sets the "limit" very low. nannie intervention can be triggered a lot sooner by a crap driver. A driver that isn't on a racing line, turning a lot harder than they should be, smashing the gas like an on/off switch will take the car to it's "limit" a lot sooner than an experienced driver.
An experienced driver can also exploit PTM by knowing what the car is going to do. (on corner exit why not just smash the gas and let the computer gradually increase power delivery on its own, that's probably the most efficient and fastest way out of the corner in some scenarios)
I learned how to drive this car by working through the PTM settings over 2 years and now RACE vs "completely off" is no different for me in lap times.
I also didn't mean to diminish the role of the fabricator. That is absolutely critical in building the cage. I was just saying that the design as far as door bars. down bars, main hoops etc are based on standards and certifications. it obviously needs to be assembled great. Cutting corners is something you should never do on a race car safety imo.
A race prepped street car I will accept that some concessions have been made compared to a fully developed tube frame race car.
With a quality system in place in my street car I personally believe it's as safe as I can currently get it and no way in hell would I want to get into an accident in it on highway lol.
im not sure if you are disagreeing, or reiterating?
on the nanny front, and there plenty of info on this, if you are past the limit, as the settings you chose and the program dictates from the sensor data present, the nannies intervene- that said, if you are on the bleeding edge limit, hypothetically, you would be as fast as is possible, and the nannies wouldn’t intervene, as you are at the limit, not exceeding the programmed envelope. The various settings allow a larger envelope, more yaw (rotation), more tire slip, more power to be put down. I hope we agree on that? If not, well, I dunno. The learning curve is difficult to test for most drivers, who pay for their hardware, and are not Randy pobst or a development driver, especially in a car that can pull a g on a skid pad and has 650hp. It takes a long time on a track to find the limit. The nannies just keep you from paying for making SOME mistakes. Will they slow hamhanded roughshod drivers (DO NOT TAKE OFFENSE NOT INTENDED TO MEAN YOU) downsometimes? Probably, because they aren’t listening to what the car is telling them. will some drivers be faster without them? Of course. But even the fastest guys seem to do a bit better w the systems developed at Ferrari, Porsche and I think in the c7 case. Ymmv, tho. And we agreed they do reward bad habits and make you look better than you are. The designers and engineers did that on purpose, they will tell you, allowing you to safely “access” more of the cars potential ����*♂️
regarding safety systems, I think we agree. I was stating that a system has to be developed, not pieces interchanged between different philosophies. Open wheel cars have a life cell, and the cars are designed to disintegrate, dissipating as much energy as possible, over the longest duration possible( in milliseconds). That is in distinction to old thinking, which was “keep making the car stronger, more rigid, to tolerate high impact loads, and the driver will be safer”. It’s dissipation of energy, not rigidity, and both come into play. NASCAR changed that thinking when DE lost his life and the COT was introduced. Open wheel was ahead of them. This was around the time of the introduction of the HANS device.
cage design is a combination of specifications from a sanctioning body, who says you have to have these bars, made of these materials connecting this. The role of the fabricator is huge. To have a truly certified cage, I believe a manufacturer must submit sample welds as well as meet the specs.
Regarding cage safety of street cars on tracks, well I agree, there’s lots of “examples”. That’s different than controlled crash testing. No crash is controlled, street or track. You can’t predict the severity, vector, etc. But you must follow certain ideas, as we both outlined. And without careful measurement of impact loads to the occupant, there is no way to say which is better in a given scenario. I would add that the engineers at the race car manufacturers and street car manufacturers take great pains to maximize safety. I’ve seen it firsthand, and the development over time. Modern race car construction allowed an occupant to sustain a 193g hit and survive. Old school rigid cage systems pre HANS never achieved 100g I believe. A harness bar that’s lower than your helmet and 4 points is not a carefully developed system. My point is simple, and not derogatory to anyone, have a plan for your safety system, use quality material, tested ideas, engineered and fabricated well. And try not to crash. That helps, too.
A helmet is just a thin sheet of composite and foam, so is the head surround ( not the halo) in F1 and its amazing how well those work. Nothing will stop the catch fence from intruding into the life cell or cage of any car if the impact is great enough, at the weak point of a system, etc. be safe out there, it’s brutal when sh*t goes wrong.
see attached https://www.racing-reference.info/showblog?id=3018
http://www.formula1-dictionary.net/g_force.html
not trying to argue. Just trying to add what I think are facts to the discussion. If I’m wrong, I apologize.
On a different note commenting to Scott's post above.
"Difflow" now has a second "track" diffuser for the C7.
The fences are longer and taller and the cutout for the tow hook is accessible.
I'm the first customer to have one but haven't got it installed yet as the car is getting some work done to it for next season prep.
The nannies, up until "Race" in PTM sets the "limit" very low. nannie intervention can be triggered a lot sooner by a crap driver. A driver that isn't on a racing line, turning a lot harder than they should be, smashing the gas like an on/off switch will take the car to it's "limit" a lot sooner than an experienced driver.
An experienced driver can also exploit PTM by knowing what the car is going to do. (on corner exit why not just smash the gas and let the computer gradually increase power delivery on its own, that's probably the most efficient and fastest way out of the corner in some scenarios)
I learned how to drive this car by working through the PTM settings over 2 years and now RACE vs "completely off" is no different for me in lap times.
I also didn't mean to diminish the role of the fabricator. That is absolutely critical in building the cage. I was just saying that the design as far as door bars. down bars, main hoops etc are based on standards and certifications. it obviously needs to be assembled great. Cutting corners is something you should never do on a race car safety imo.
A race prepped street car I will accept that some concessions have been made compared to a fully developed tube frame race car.
With a quality system in place in my street car I personally believe it's as safe as I can currently get it and no way in hell would I want to get into an accident in it on highway lol.
im not sure if you are disagreeing, or reiterating?
on the nanny front, and there plenty of info on this, if you are past the limit, as the settings you chose and the program dictates from the sensor data present, the nannies intervene- that said, if you are on the bleeding edge limit, hypothetically, you would be as fast as is possible, and the nannies wouldn’t intervene, as you are at the limit, not exceeding the programmed envelope. The various settings allow a larger envelope, more yaw (rotation), more tire slip, more power to be put down. I hope we agree on that? If not, well, I dunno. The learning curve is difficult to test for most drivers, who pay for their hardware, and are not Randy pobst or a development driver, especially in a car that can pull a g on a skid pad and has 650hp. It takes a long time on a track to find the limit. The nannies just keep you from paying for making SOME mistakes. Will they slow hamhanded roughshod drivers (DO NOT TAKE OFFENSE NOT INTENDED TO MEAN YOU) downsometimes? Probably, because they aren’t listening to what the car is telling them. will some drivers be faster without them? Of course. But even the fastest guys seem to do a bit better w the systems developed at Ferrari, Porsche and I think in the c7 case. Ymmv, tho. And we agreed they do reward bad habits and make you look better than you are. The designers and engineers did that on purpose, they will tell you, allowing you to safely “access” more of the cars potential ����*♂️
regarding safety systems, I think we agree. I was stating that a system has to be developed, not pieces interchanged between different philosophies. Open wheel cars have a life cell, and the cars are designed to disintegrate, dissipating as much energy as possible, over the longest duration possible( in milliseconds). That is in distinction to old thinking, which was “keep making the car stronger, more rigid, to tolerate high impact loads, and the driver will be safer”. It’s dissipation of energy, not rigidity, and both come into play. NASCAR changed that thinking when DE lost his life and the COT was introduced. Open wheel was ahead of them. This was around the time of the introduction of the HANS device.
cage design is a combination of specifications from a sanctioning body, who says you have to have these bars, made of these materials connecting this. The role of the fabricator is huge. To have a truly certified cage, I believe a manufacturer must submit sample welds as well as meet the specs.
Regarding cage safety of street cars on tracks, well I agree, there’s lots of “examples”. That’s different than controlled crash testing. No crash is controlled, street or track. You can’t predict the severity, vector, etc. But you must follow certain ideas, as we both outlined. And without careful measurement of impact loads to the occupant, there is no way to say which is better in a given scenario. I would add that the engineers at the race car manufacturers and street car manufacturers take great pains to maximize safety. I’ve seen it firsthand, and the development over time. Modern race car construction allowed an occupant to sustain a 193g hit and survive. Old school rigid cage systems pre HANS never achieved 100g I believe. A harness bar that’s lower than your helmet and 4 points is not a carefully developed system. My point is simple, and not derogatory to anyone, have a plan for your safety system, use quality material, tested ideas, engineered and fabricated well. And try not to crash. That helps, too.
A helmet is just a thin sheet of composite and foam, so is the head surround ( not the halo) in F1 and its amazing how well those work. Nothing will stop the catch fence from intruding into the life cell or cage of any car if the impact is great enough, at the weak point of a system, etc. be safe out there, it’s brutal when sh*t goes wrong.
see attached https://www.racing-reference.info/showblog?id=3018
http://www.formula1-dictionary.net/g_force.html
not trying to argue. Just trying to add what I think are facts to the discussion. If I’m wrong, I apologize.
On a different note commenting to Scott's post above.
"Difflow" now has a second "track" diffuser for the C7.
The fences are longer and taller and the cutout for the tow hook is accessible.
I'm the first customer to have one but haven't got it installed yet as the car is getting some work done to it for next season prep.
Last edited by lobsterroboto; 12-09-2018 at 06:20 PM.
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Bad_AX (12-09-2018)
12-09-2018, 06:50 PM
#98
Advanced
I thought we were on the same page... this forum is just full of people who like to argue! And your car looks like you ARE very serious!
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lobsterroboto (12-09-2018)
12-09-2018, 07:20 PM
#99
Drifting
Member Since: Jun 2016
Posts: 1,266
Received 310 Likes
on
213 Posts
2020 Corvette of the Year Finalist (track prepared)
C7 of Year Winner (track prepared) 2019
over the last few years my opinion and overall knowledge about driving has changed considerably.
Sometimes needing a bullshit detector is needed, other times it's just knowing when I may not actually be right about something.
The autocrossing/roadracing subforum is typically a bit better and lots of the gang have been at it a while.
12-09-2018, 07:26 PM
#100
Track Rat
Thread Starter
Good stuff there Scott. Why do you think an ARE or Dailey dry sump is needed? Supposedly the ZR1 has exceeded 1.9G in testing. To be honest, my experience with the aftermarket systems is that they are kind of a pain to deal with. Catch cans filling with oil, having to more oil lines to do an oil change, special startup procedures, etc.