ZTK rear wing
10-28-2023, 07:34 AM
#1
Racer
Thread Starter
ZTK rear wing
Hi Guys,
Can a non ZTK C7 ZR1 be converted to a ZTK car? Or is it more than cosmetics that make a ZTK ZR1? Also, do any of the aftermarket companies make a ZTK rear wing for a non ZTK C7 ZR1? I found a few vendors who make the ZTK wing for non ZR1 cars but I haven't found a rear wing for a C7 ZR1. Why, I'm thinking of buying a non ZTK C7 ZR1 and converting it to a ZTK. You think I would know this since I currently own a ZTK ZR1. Thinking of buying another one but it's not a ZTK car and I'd like to convert it.
Can a non ZTK C7 ZR1 be converted to a ZTK car? Or is it more than cosmetics that make a ZTK ZR1? Also, do any of the aftermarket companies make a ZTK rear wing for a non ZTK C7 ZR1? I found a few vendors who make the ZTK wing for non ZR1 cars but I haven't found a rear wing for a C7 ZR1. Why, I'm thinking of buying a non ZTK C7 ZR1 and converting it to a ZTK. You think I would know this since I currently own a ZTK ZR1. Thinking of buying another one but it's not a ZTK car and I'd like to convert it.
10-28-2023, 08:50 AM
#2
Safety Car
ZTK is more than just the rear wing. Off the top of my head, there's differences in the suspension as well as the tires. I would think a conversion would not be too difficult although I have no idea how the different suspension settings would affect the car at speed if you just bolted on the high wing.
10-28-2023, 11:04 AM
#3
Heel & Toe
Yes, it's possible to convert a non-ZTK C7 ZR1 to a ZTK car, but it involves more than just cosmetic changes. You would need to obtain and install the performance-enhancing components of the ZTK package, such as the larger wing, front splitter, specific tires, and suspension tuning. As for aftermarket options, you may need to check with specialized shops for ZTK-style rear wings for non-ZTK C7 ZR1s. Also visit carwooow
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danm1 (10-29-2023)
10-28-2023, 12:26 PM
#4
Pro Mechanic
Pro Mechanic
It's possible but not practical.
Not only would you need all the cosmetic and aero parts but you'd need the springs, front stab. bar mounts, the MR, stability enhancement and MagnaSteer software, the tires, and perhaps other items. Even if you could get all the hardware, you'd still have to find a way to reprogram the chassis computer. That is generally not a DIY process.
On the specific question of a high-wing on a low-wing car,–you should not just bolt the high wing on the low wing car because, if you do you'll have at higher speeds you'll have significant downforce on the rear but no change in downforce on the front that will make a car that has significant understeer– possibly to the point of being unsafe at higher speeds. What you need is both the high-wing and the front"under wing" that goes with a high wing car.
Not only would you need all the cosmetic and aero parts but you'd need the springs, front stab. bar mounts, the MR, stability enhancement and MagnaSteer software, the tires, and perhaps other items. Even if you could get all the hardware, you'd still have to find a way to reprogram the chassis computer. That is generally not a DIY process.
On the specific question of a high-wing on a low-wing car,–you should not just bolt the high wing on the low wing car because, if you do you'll have at higher speeds you'll have significant downforce on the rear but no change in downforce on the front that will make a car that has significant understeer– possibly to the point of being unsafe at higher speeds. What you need is both the high-wing and the front"under wing" that goes with a high wing car.
Last edited by Hib Halverson; 10-28-2023 at 12:43 PM.
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10-28-2023, 07:04 PM
#5
Drifting
I know aero balance is a thing, but I think you guys are thinking the car will be understeering off a cliff or whatever if you convert a low wing to a ZTK. Sure, there’s a difference. But it’s not going to have the front end just lift up and wheelie at high enough speed.
Two points:
First off, you actually can aero balance if you put the high wing on. On a low wing car, there are strakes installed in front of the front tires. These strakes actually reduce the downforce of the front underwing. Remove these strakes and add the gravel catching side plates, and voila you have the full ZTK aero. Yes sure you still don’t have the stiffer springs to make up for the extra downforce, but the aero is in fact balanced.
Secondly, if you do already have a ZTK rear wing, it has two positions. Setting the higher angle will of course increase the downforce. So where does once set anything on the front to account for the increase on the rear?
Two points:
First off, you actually can aero balance if you put the high wing on. On a low wing car, there are strakes installed in front of the front tires. These strakes actually reduce the downforce of the front underwing. Remove these strakes and add the gravel catching side plates, and voila you have the full ZTK aero. Yes sure you still don’t have the stiffer springs to make up for the extra downforce, but the aero is in fact balanced.
Secondly, if you do already have a ZTK rear wing, it has two positions. Setting the higher angle will of course increase the downforce. So where does once set anything on the front to account for the increase on the rear?
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danm1 (10-29-2023)
10-29-2023, 01:20 PM
#6
Pro Mechanic
Pro Mechanic
"TheRobSJ"...you've actually tested this on the track or you are just speculating taking those actions would "aero balance" a low-wing car fitted with the high wing.?
If you have tested this in a race track environment, please post some of your data to support your claims about aero balancing such a configuration.
If you have tested this in a race track environment, please post some of your data to support your claims about aero balancing such a configuration.
I know aero balance is a thing, but I think you guys are thinking the car will be understeering off a cliff or whatever if you convert a low wing to a ZTK. Sure, there’s a difference. But it’s not going to have the front end just lift up and wheelie at high enough speed.
Two points:
First off, you actually can aero balance if you put the high wing on. On a low wing car, there are strakes installed in front of the front tires. These strakes actually reduce the downforce of the front underwing. Remove these strakes and add the gravel catching side plates, and voila you have the full ZTK aero. Yes sure you still don’t have the stiffer springs to make up for the extra downforce, but the aero is in fact balanced.
Secondly, if you do already have a ZTK rear wing, it has two positions. Setting the higher angle will of course increase the downforce. So where does once set anything on the front to account for the increase on the rear?
Two points:
First off, you actually can aero balance if you put the high wing on. On a low wing car, there are strakes installed in front of the front tires. These strakes actually reduce the downforce of the front underwing. Remove these strakes and add the gravel catching side plates, and voila you have the full ZTK aero. Yes sure you still don’t have the stiffer springs to make up for the extra downforce, but the aero is in fact balanced.
Secondly, if you do already have a ZTK rear wing, it has two positions. Setting the higher angle will of course increase the downforce. So where does once set anything on the front to account for the increase on the rear?
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17 Z06/Z07 (10-29-2023)
10-29-2023, 10:26 PM
#7
Drifting
"TheRobSJ"...you've actually tested this on the track or you are just speculating taking those actions would "aero balance" a low-wing car fitted with the high wing.?
If you have tested this in a race track environment, please post some of your data to support your claims about aero balancing such a configuration.
If you have tested this in a race track environment, please post some of your data to support your claims about aero balancing such a configuration.
That’s it. Whether it’s truly balanced? Well we’d need the scales for that. I’m sure there’s more downforce in the rear, especially with the wing set in the higher angle. But you can make the exact same aero profile of the ZTK car and have that same level of downforce that the Corvettes engineers specified on the front and rear.
I see tons of cars at the track that add a whole bunch of downforce in the back with a gigantic wing that looks like it came off a GT3 car. With minimal to no aero added to the front.
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ernhart333 (11-07-2023)
11-07-2023, 02:22 PM
#8
Pro Mechanic
Pro Mechanic
Sorry I have been absent from this thread for a while. Only justification I have is the "Swiftie Excuse"...a lot going on at the moment.
Today, I had some time to drill down into this high-wing installed on a low-wing car issue. Before posting this, to get additional insight to the problems created when a base ZR1 gets a high-wing, I contacted, Jim Mero, a good friend of mine who was the lead ride-and-handling development engineer on Corvette from 2004 to 2018 and whose last project was the '19 ZR1.
Chassis-wise, the key differences between a ZR1 w/o ZTK and one with ZTK are:
30% higher front spring rate
13% higher rear spring rate
higher durometer from stabilizer bar mounts
"Unstraked" front underwing with end plates.
Cup tires rather than full tread depth tires
Different MR calibration.
At its top speed, 205-mph, the ZTK aero components add about 900-lbs downforce, 400 at the front, from the end-plated underwing, and 500-lbs at the rear from the high-wing. Even though downforce is proportional to the square of the speed, the effect of downforce at lower speeds is less, but the aero balance between front and rear would likely be the same and, obviously, arill affects the dynamics of the car.
At Tiergarten, a high-speed, left sweeper on the Nordschleife course at Nurburgring, a ZR1/ZTK with a talented driver at the wheel will be at WOT and about 180-mph in that turn. I have seen video footage showing that, so I know it can be done.
If you were in base ZR1 fitted with the ZTK high-wing, how do you think the car is going to handle under the same circumstances? Well, before you answer, consider these situations:
> Softer front stabilizer bar mounts are like going to a smaller diameter bar and can result in a mechanical (ie: non-aero), steady state oversteer effect as well as a reduction in steering response and non-linear steering dynamics.
> 500-lbs downforce in the rear with a 13% softer rear spring will reduce the rake of the car, which is a "who-the-hell-knows" reduction in overall downforce and aero balance because the car's rake is a huge contributing factor to overall downforce.
> Less front downforce from the reduced rake and the front wing strakes combined with a 30% softer front spring.
> Incorrect damping because the MagnaRide calibration was developed for the low-wing ZR1 rather than a low-wing car with the high-wing or, for that matter, a low-wing car converted to ZTK.
All these problems could make the car pretty scary at high speed.
Prefer a more domestic example than driving the Nordschleife? Take Big Willow for instance. A quick lap has you flat-out from the exit of T6 to a slight lift in T8 and then WOT to the entrance of T9. Good drivers in well-sorted cars can do that. The above points in mind, do you think you could drive a low-wing ZR1 fitted with only the ZTK rear wing flat out from exit 6 to entrance 9?
Or, heck...what about one of those "tons of cars" with big rear wings from GT3 cars and no front aero...think their drivers could take Nordschleife Tiergarten or Big Willow, T6 to T9 as above?
At the risk of repetition, here's some of Mero's comments.
Finally, Jim said this (I added the red type style for emphasis)
My bottom line?
If the OP wants to put a high wing on a low wing car then go do track days, I think he/she ought to read the above carefully, however, if the car is for show and street driving and not tracking and the ZTK wing is desired because it looks cooler than the low wing–and, I agree, it does look better–for sure, bolt that wing on.
Today, I had some time to drill down into this high-wing installed on a low-wing car issue. Before posting this, to get additional insight to the problems created when a base ZR1 gets a high-wing, I contacted, Jim Mero, a good friend of mine who was the lead ride-and-handling development engineer on Corvette from 2004 to 2018 and whose last project was the '19 ZR1.
Chassis-wise, the key differences between a ZR1 w/o ZTK and one with ZTK are:
30% higher front spring rate
13% higher rear spring rate
higher durometer from stabilizer bar mounts
"Unstraked" front underwing with end plates.
Cup tires rather than full tread depth tires
Different MR calibration.
At its top speed, 205-mph, the ZTK aero components add about 900-lbs downforce, 400 at the front, from the end-plated underwing, and 500-lbs at the rear from the high-wing. Even though downforce is proportional to the square of the speed, the effect of downforce at lower speeds is less, but the aero balance between front and rear would likely be the same and, obviously, arill affects the dynamics of the car.
At Tiergarten, a high-speed, left sweeper on the Nordschleife course at Nurburgring, a ZR1/ZTK with a talented driver at the wheel will be at WOT and about 180-mph in that turn. I have seen video footage showing that, so I know it can be done.
If you were in base ZR1 fitted with the ZTK high-wing, how do you think the car is going to handle under the same circumstances? Well, before you answer, consider these situations:
> Softer front stabilizer bar mounts are like going to a smaller diameter bar and can result in a mechanical (ie: non-aero), steady state oversteer effect as well as a reduction in steering response and non-linear steering dynamics.
> 500-lbs downforce in the rear with a 13% softer rear spring will reduce the rake of the car, which is a "who-the-hell-knows" reduction in overall downforce and aero balance because the car's rake is a huge contributing factor to overall downforce.
> Less front downforce from the reduced rake and the front wing strakes combined with a 30% softer front spring.
> Incorrect damping because the MagnaRide calibration was developed for the low-wing ZR1 rather than a low-wing car with the high-wing or, for that matter, a low-wing car converted to ZTK.
All these problems could make the car pretty scary at high speed.
Prefer a more domestic example than driving the Nordschleife? Take Big Willow for instance. A quick lap has you flat-out from the exit of T6 to a slight lift in T8 and then WOT to the entrance of T9. Good drivers in well-sorted cars can do that. The above points in mind, do you think you could drive a low-wing ZR1 fitted with only the ZTK rear wing flat out from exit 6 to entrance 9?
Or, heck...what about one of those "tons of cars" with big rear wings from GT3 cars and no front aero...think their drivers could take Nordschleife Tiergarten or Big Willow, T6 to T9 as above?
At the risk of repetition, here's some of Mero's comments.
With just a rear wing, you'll have more front lift, reduced rake, inducing aero understeer and overall decreased downforce. If somebody wanted to install the ZTK rear wing on a base C7 ZR1, I would suggest reducing risk by installing the (rest of the) ZTK (suspension pieces) and front aero components. If not, how the car would drive at max velocity is a big question mark. Honestly, that is a big risk, messing with the aerodynamics at maximum velocity. It is a complete unknown that could lead to a significant reduction in drivability at an incredibly high speed.
I think it would be foolish to put one complement of a complete system on a car capable of over 200 mph and hope for the best. We spent a lot of time tuning these cars and maximum velocity and just adding the rear wing would be a very risky situation.
If the OP wants to put a high wing on a low wing car then go do track days, I think he/she ought to read the above carefully, however, if the car is for show and street driving and not tracking and the ZTK wing is desired because it looks cooler than the low wing–and, I agree, it does look better–for sure, bolt that wing on.
Last edited by Hib Halverson; 11-07-2023 at 02:44 PM. Reason: sig line
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Basil2000 (11-07-2023)
11-08-2023, 08:10 AM
#9
Instructor
Good morning Hib:
I am a novice on the track, so please forgive the noob question. Although I have owned Vette's for many years, the ZR1 is the first one I have spent any track time in. Mine is a non-ZTK (low wing) car FYI.
I was wondering if you could just give me a sense of how differently a ZTK car would drive on the track (compared to my own). My experience is primarily at Mid Ohio FYI. I know that's a broad question, but I can't think of a better person to ask!
Compared to my previous Katech C6 Z, this car is just flat out amazing. Thanks in advance for any input.
All the best,
kev
I am a novice on the track, so please forgive the noob question. Although I have owned Vette's for many years, the ZR1 is the first one I have spent any track time in. Mine is a non-ZTK (low wing) car FYI.
I was wondering if you could just give me a sense of how differently a ZTK car would drive on the track (compared to my own). My experience is primarily at Mid Ohio FYI. I know that's a broad question, but I can't think of a better person to ask!
Compared to my previous Katech C6 Z, this car is just flat out amazing. Thanks in advance for any input.
All the best,
kev
Last edited by kevin nevius; 11-08-2023 at 09:57 AM.
11-11-2023, 02:14 PM
#10
Drifting
At its top speed, 205-mph, the ZTK aero components add about 900-lbs downforce, 400 at the front, from the end-plated underwing, and 500-lbs at the rear from the high-wing. Even though downforce is proportional to the square of the speed, the effect of downforce at lower speeds is less, but the aero balance between front and rear would likely be the same and, obviously, arill affects the dynamics of the car.
At Tiergarten, a high-speed, left sweeper on the Nordschleife course at Nurburgring, a ZR1/ZTK with a talented driver at the wheel will be at WOT and about 180-mph in that turn. I have seen video footage showing that, so I know it can be done.
If you were in base ZR1 fitted with the ZTK high-wing, how do you think the car is going to handle under the same circumstances? Well, before you answer, consider these situations:
> Softer front stabilizer bar mounts are like going to a smaller diameter bar and can result in a mechanical (ie: non-aero), steady state oversteer effect as well as a reduction in steering response and non-linear steering dynamics.
> 500-lbs downforce in the rear with a 13% softer rear spring will reduce the rake of the car, which is a "who-the-hell-knows" reduction in overall downforce and aero balance because the car's rake is a huge contributing factor to overall downforce.
> Less front downforce from the reduced rake and the front wing strakes combined with a 30% softer front spring.
> Incorrect damping because the MagnaRide calibration was developed for the low-wing ZR1 rather than a low-wing car with the high-wing or, for that matter, a low-wing car converted to ZTK.
All these problems could make the car pretty scary at high speed.
Prefer a more domestic example than driving the Nordschleife? Take Big Willow for instance. A quick lap has you flat-out from the exit of T6 to a slight lift in T8 and then WOT to the entrance of T9. Good drivers in well-sorted cars can do that. The above points in mind, do you think you could drive a low-wing ZR1 fitted with only the ZTK rear wing flat out from exit 6 to entrance 9?
Or, heck...what about one of those "tons of cars" with big rear wings from GT3 cars and no front aero...think their drivers could take Nordschleife Tiergarten or Big Willow, T6 to T9 as above?
I honestly don’t have the energy to debate this much more. In the end, OP or anyone else (myself included) thinking about converting a low wing to a ZTK wing?
If all you ever do with your ZR1 is cars & coffee meets or whatever and will never take the car deep into the 100+mph speeds? High wing, low wing, no wing…doesn’t matter. The amount of downforce gained or lost won’t upset the handling to much of a perceptible level.
11-11-2023, 03:06 PM
#11
Pro Mechanic
Pro Mechanic
11-11-2023, 03:28 PM
#12
Drifting
As a professional writer, I would hope you know the difference of me saying “much more” versus if I had said done with this.
Years ago, my dad would go down rabbit holes with you over whatever the flavor of the month debate might have been on whatever Corvette based forum you were both on. I don’t intend to do the same.
So after this sentence, I am in fact done with this.
Years ago, my dad would go down rabbit holes with you over whatever the flavor of the month debate might have been on whatever Corvette based forum you were both on. I don’t intend to do the same.
So after this sentence, I am in fact done with this.
11-11-2023, 03:34 PM
#13
Pro Mechanic
Pro Mechanic
Good morning Hib:
I am a novice on the track, so please forgive the noob question. Although I have owned Vette's for many years, the ZR1 is the first one I have spent any track time in. Mine is a non-ZTK (low wing) car FYI.
I was wondering if you could just give me a sense of how differently a ZTK car would drive on the track (compared to my own). My experience is primarily at Mid Ohio FYI. I know that's a broad question, but I can't think of a better person to ask!
Compared to my previous Katech C6 Z, this car is just flat-out amazing. Thanks in advance for any input.
All the best,
kev
I am a novice on the track, so please forgive the noob question. Although I have owned Vette's for many years, the ZR1 is the first one I have spent any track time in. Mine is a non-ZTK (low wing) car FYI.
I was wondering if you could just give me a sense of how differently a ZTK car would drive on the track (compared to my own). My experience is primarily at Mid Ohio FYI. I know that's a broad question, but I can't think of a better person to ask!
Compared to my previous Katech C6 Z, this car is just flat-out amazing. Thanks in advance for any input.
All the best,
kev
Do you "need" the aero and stiffer springs, etc. of a ZTK?
Well...for the most part, that depends on two things.
1) The kinds of tracks you're driving. If you're on courses that allow high speeds, ZTK will be an advantage
2) How close to the car's limits your driving. If you're regularly close to the car's limits, especially on high-speed tracks, ZTK will be an advantage.
You say you're a noob to the whole tracking thing, so I wouldn't worry much about ZTK. Concentrate on learning the basics of performance driving. Once you get comfortable at an intermediate level of skill/experience, then start worrying about adding aero enhancements and stiffer suspension.
That said, there are two areas I'd change. First: tires. Tracking with the stock tires on a low-wing tire is going to result in quicking wearing those tires. I'd get a second set of wheels and put some tire intended for track use on them. Michelin Pillot Sport Cup 2 is good and there are other choices. Secondly: wheel alignment. I'd have the car aligned to at least the stock ZTK alignment specs.
Read the Owner's Manual on Performance Traction Management (PTM) and all the various driving modes. On PTM, I recommend you try TRAC 2, first. Also take a look at Chevrolet's Track Preparation Guide which is attached to this post. Not all the recommendations in that Guide would pertain to what you're going to be doing as you learn the skills of performance driving, however once you're into to the intermediate level at the track, more of them should be considered.
If you can't afford a weekend at the Ron Fellows School, then read some books. A classic on performance driving is Alan Johnson's, Driving in Competition. Long out of print, it's still a great book on the basics. Used books stores or, maybe eBay for that. Another good one is Ross Bently's .
Good luck.
Have fun!
Last edited by Hib Halverson; 11-11-2023 at 09:23 PM.
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kevin nevius (11-15-2023)
11-12-2023, 09:00 AM
#14
Good morning Hib:
I am a novice on the track, so please forgive the noob question. Although I have owned Vette's for many years, the ZR1 is the first one I have spent any track time in. Mine is a non-ZTK (low wing) car FYI.
I was wondering if you could just give me a sense of how differently a ZTK car would drive on the track (compared to my own). My experience is primarily at Mid Ohio FYI. I know that's a broad question, but I can't think of a better person to ask!
Compared to my previous Katech C6 Z, this car is just flat out amazing. Thanks in advance for any input.
All the best,
kev
I am a novice on the track, so please forgive the noob question. Although I have owned Vette's for many years, the ZR1 is the first one I have spent any track time in. Mine is a non-ZTK (low wing) car FYI.
I was wondering if you could just give me a sense of how differently a ZTK car would drive on the track (compared to my own). My experience is primarily at Mid Ohio FYI. I know that's a broad question, but I can't think of a better person to ask!
Compared to my previous Katech C6 Z, this car is just flat out amazing. Thanks in advance for any input.
All the best,
kev
I agree with All the things Hib mentioned in the previous post(s).
I just wanted to let you know that the track calibrations for the low wing ZR1 were developed exclusively for that car. With a track alignment, the car drives incredibly well. If you search on YouTube for ZR1 Nurburgring, many of the shots you see are the low wing ZR1 on the Nürburgring.
Thank you, Jim
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kevin nevius (11-15-2023)
11-13-2023, 08:08 AM
#15
Instructor
Mr. Mero and Halverson:
Thank you so much for your replies, I respect and admire you both and I so very much appreciate your comments!
This is exactly why I love this forum so much - I enjoy the conversation, and have learned a ton since joining. Thank you both again!
Wishing you a great upcoming Thanksgiving, and Holiday season!
kev
Thank you so much for your replies, I respect and admire you both and I so very much appreciate your comments!
This is exactly why I love this forum so much - I enjoy the conversation, and have learned a ton since joining. Thank you both again!
Wishing you a great upcoming Thanksgiving, and Holiday season!
kev
11-13-2023, 01:22 PM
#16
Le Mans Master
If I did a top speed run (mile or longer) on a straight road, would I get into trouble during braking if I removed the ZTK wing for reduced drag? I remember my C6 ZR1 would 'dance' a little at the end of the straightaway during heavy braking while the C7 ZR1 ZTK feels solidly planted.
11-15-2023, 01:21 PM
#17
Race Director
Zr1
It's possible but not practical.
Not only would you need all the cosmetic and aero parts but you'd need the springs, front stab. bar mounts, the MR, stability enhancement and MagnaSteer software, the tires, and perhaps other items. Even if you could get all the hardware, you'd still have to find a way to reprogram the chassis computer. That is generally not a DIY process.
On the specific question of a high-wing on a low-wing car,–you should not just bolt the high wing on the low wing car because, if you do you'll have at higher speeds you'll have significant downforce on the rear but no change in downforce on the front that will make a car that has significant understeer– possibly to the point of being unsafe at higher speeds. What you need is both the high-wing and the front"under wing" that goes with a high wing car.
Not only would you need all the cosmetic and aero parts but you'd need the springs, front stab. bar mounts, the MR, stability enhancement and MagnaSteer software, the tires, and perhaps other items. Even if you could get all the hardware, you'd still have to find a way to reprogram the chassis computer. That is generally not a DIY process.
On the specific question of a high-wing on a low-wing car,–you should not just bolt the high wing on the low wing car because, if you do you'll have at higher speeds you'll have significant downforce on the rear but no change in downforce on the front that will make a car that has significant understeer– possibly to the point of being unsafe at higher speeds. What you need is both the high-wing and the front"under wing" that goes with a high wing car.
11-15-2023, 02:25 PM
#18
Pro Mechanic
Pro Mechanic
If I did a top-speed run (mile or longer) on a straight road, would I get into trouble during braking if I removed the ZTK wing for reduced drag? I remember my C6 ZR1 would 'dance' a little at the end of the straightaway during heavy braking while the C7 ZR1 ZTK feels solidly planted.
The top speed of a ZTK car is around 200 mph. At that speed, you'll have about 400 lbs downforce on the nose and 500 lbs in the rear. With only a mile to run, you're not going to get close to 200 but still, you will have some aero and during heavy braking weight transfers to the nose and the front ride height will decrease. As downforce on ZR1s is partially dependent on the car's rake and the rake increases as the nose lowers, downforce on the front of the car might increase. So, now...with the possibility of aero oversteer, think about what happens if you remove the high-wing and eliminate most of the rear downforce.
(your thinking)
Right, with the car heavy on the nose and light in the back, all it takes is a slight loss of longitudinal stability, and the back end steps out. Ok, now–to run the highest speed possible in a mile, you need the LT5's maximum power. You only get that in TRAC 5 and with at least 98-octane fuel if it's cool out and 100-octane fuel if it's warm out. Knowing that in TRAC 5, TCS and SES are disabled. Will ABS save your ***? Maybe ABS could mitigate a catastrophe but even if it can, it still cannot violate the laws of physics.
Oh, but wait–there's more. What about the lack of the high-wing on the car's aero during acceleration? You'll need every bit of the engine's 755-hp. What do you think will happen if at WOT, the rear tires break loose and the back end steps out, say–150 or so. With no TCS or SES, can you react quick enough? Your first instinct might be to abruptly lift and brake which aggravates the above conditions.
If you are going to try something as nutty as a high-speed run in a ZR1/ZTK with no rear wing, dude...make sure your life and health insurance are paid up.
You'd be better to convert the car to the base aero configuration, ie: straked front wing and the low rear wing. Then, find a very long, straight and smooth road and use TRAC 5. Maybe enter one of those events held in Florida on NASA's 15,000-ft "Space Shuttle Runway."
BTW, the base ZR1's top speed of 212 mph was verified at Pappenburg in Germany. Click here to see that. It's true that 215 mph is often cited as the car's top speed and under perfect conditions, it might go that fast, but 212 is the number based on two runs, north and south. Pappenburg is at near sea level and, while GM didn't release information on atmospheric conditions for those runs, it would be interesting to know what they were. When it's cold out, the engine would make more power, but when it's warm out, downforce is reduced and, thus, drag would be reduced. Ideally, air density would be such that the benefits to both engine and aero were optimal.
Let me know what you think.
The following 3 users liked this post by Hib Halverson:
11-15-2023, 08:45 PM
#19
Le Mans Master
Well...let's drill down into this latest "high-wing" quandary.
The top speed of a ZTK car is around 200 mph. At that speed, you'll have about 400 lbs downforce on the nose and 500 lbs in the rear. With only a mile to run, you're not going to get close to 200 but still, you will have some aero and during heavy braking weight transfers to the nose and the front ride height will decrease. As downforce on ZR1s is partially dependent on the car's rake and the rake increases as the nose lowers, downforce on the front of the car might increase. So, now...with the possibility of aero oversteer, think about what happens if you remove the high-wing and eliminate most of the rear downforce.
(your thinking)
Right, with the car heavy on the nose and light in the back, all it takes is a slight loss of longitudinal stability, and the back end steps out. Ok, now–to run the highest speed possible in a mile, you need the LT5's maximum power. You only get that in TRAC 5 and with at least 98-octane fuel if it's cool out and 100-octane fuel if it's warm out. Knowing that in TRAC 5, TCS and SES are disabled. Will ABS save your ***? Maybe ABS could mitigate a catastrophe but even if it can, it still cannot violate the laws of physics.
Oh, but wait–there's more. What about the lack of the high-wing on the car's aero during acceleration? You'll need every bit of the engine's 755-hp. What do you think will happen if at WOT, the rear tires break loose and the back end steps out, say–150 or so. With no TCS or SES, can you react quick enough? Your first instinct might be to abruptly lift and brake which aggravates the above conditions.
If you are going to try something as nutty as a high-speed run in a ZR1/ZTK with no rear wing, dude...make sure your life and health insurance are paid up.
You'd be better to convert the car to the base aero configuration, ie: straked front wing and the low rear wing. Then, find a very long, straight and smooth road and use TRAC 5. Maybe enter one of those events held in Florida on NASA's 15,000-ft "Space Shuttle Runway."
BTW, the base ZR1's top speed of 212 mph was verified at Pappenburg in Germany. Click here to see that. It's true that 215 mph is often cited as the car's top speed and under perfect conditions, it might go that fast, but 212 is the number based on two runs, north and south. Pappenburg is at near sea level and, while GM didn't release information on atmospheric conditions for those runs, it would be interesting to know what they were. When it's cold out, the engine would make more power, but when it's warm out, downforce is reduced and, thus, drag would be reduced. Ideally, air density would be such that the benefits to both engine and aero were optimal.
Let me know what you think.
The top speed of a ZTK car is around 200 mph. At that speed, you'll have about 400 lbs downforce on the nose and 500 lbs in the rear. With only a mile to run, you're not going to get close to 200 but still, you will have some aero and during heavy braking weight transfers to the nose and the front ride height will decrease. As downforce on ZR1s is partially dependent on the car's rake and the rake increases as the nose lowers, downforce on the front of the car might increase. So, now...with the possibility of aero oversteer, think about what happens if you remove the high-wing and eliminate most of the rear downforce.
(your thinking)
Right, with the car heavy on the nose and light in the back, all it takes is a slight loss of longitudinal stability, and the back end steps out. Ok, now–to run the highest speed possible in a mile, you need the LT5's maximum power. You only get that in TRAC 5 and with at least 98-octane fuel if it's cool out and 100-octane fuel if it's warm out. Knowing that in TRAC 5, TCS and SES are disabled. Will ABS save your ***? Maybe ABS could mitigate a catastrophe but even if it can, it still cannot violate the laws of physics.
Oh, but wait–there's more. What about the lack of the high-wing on the car's aero during acceleration? You'll need every bit of the engine's 755-hp. What do you think will happen if at WOT, the rear tires break loose and the back end steps out, say–150 or so. With no TCS or SES, can you react quick enough? Your first instinct might be to abruptly lift and brake which aggravates the above conditions.
If you are going to try something as nutty as a high-speed run in a ZR1/ZTK with no rear wing, dude...make sure your life and health insurance are paid up.
You'd be better to convert the car to the base aero configuration, ie: straked front wing and the low rear wing. Then, find a very long, straight and smooth road and use TRAC 5. Maybe enter one of those events held in Florida on NASA's 15,000-ft "Space Shuttle Runway."
BTW, the base ZR1's top speed of 212 mph was verified at Pappenburg in Germany. Click here to see that. It's true that 215 mph is often cited as the car's top speed and under perfect conditions, it might go that fast, but 212 is the number based on two runs, north and south. Pappenburg is at near sea level and, while GM didn't release information on atmospheric conditions for those runs, it would be interesting to know what they were. When it's cold out, the engine would make more power, but when it's warm out, downforce is reduced and, thus, drag would be reduced. Ideally, air density would be such that the benefits to both engine and aero were optimal.
Let me know what you think.
LOL on the insurance warning. I don't need life insurance, but have excellent health insurance coverage. It certainly would not worth to have a lifelong permanent disability as a consequence of a mishap at top speed.
I still remember the story about Car and Driver chief editor, Csaba Csere's accident in what I recall a highly modified Lingenfelter F-body car's top speed attempt at the salt flats. He had packed a lot of weight in the trunk to mitigate high speed lift until it didn't.
11-16-2023, 11:52 AM
#20
Burning Brakes
