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I am planning to track my Z51 with mag ride if/when my car eventually arrives. If my info is correct, the curb weight of a 1LT with Z51, with a full tank of gas is 3577 lbs. If I run with 1/2 a tank of gas, weight will drop to 3519 lbs. Existing Front Rims are 25.7 lbs. and the run flat tires are about 27 lbs. Rear Rims are 32.1 lbs and rear run flat tires are about 35 lbs. My plan is to move to 19" custom fully forged rims (still working with a supplier). Rims will be JWL certified and have a 1800 lb wheel load rating. Front weights are expected to be 20.5 lbs and Rears 21.6 lbs. Moving to Michelin Pilot Sport Cup 2's. Fronts will be 265/30/19 which gives me 20mm more front tire width with a 1.9% reduction in diameter and a weight of 23 lbs. Rears will be 325/30/19 which also gives me 20 mm more rear tire width with a 1.8% reduction in diameter and a weight of 31 lbs. Because the front and rear diameter reductions are almost identical, there should be no "computer" issues. Slight higher percentage of increase in tire width at the front will help with any understeer. I plan to keep the rim offsets of 52 mm Front and 64 mm Rear exactly the same even though it will probably look better with a wider stance. Keeping the offsets the same will ensure that all the work the Corvette engineers did on suspension setting, spring rates, scrub radius, etc will remain completely unaffected. Total unsprung weight reduction will be 9.2 lbs per front rim/tire combo and 14.5 lbs per rear rim/tire combo. Total unsprung weight loss will be about 47.4 lbs. With a goal to lose a total of 100 lbs, I will replace the battery with an Anti-Gravity lithium battery for a savings of about 30 lbs (dropping weight mounted high in the chassis is also good) for a total of about 77 lbs. which leaves me 23 lbs short still but still down to about 3442 lbs. with 1/2 tank of gas. Looking then at a race seat or 2 piece rotors (estimating these will be 10 lbs each corner when the market supplies them) to get the extra 23 lbs or even better to loose over 42 lbs to get down below 3400 lbs! I think these will provide a big difference on the track........less weight and more tire on the road. I guess I could also lose a few pounds myself.... In terms of suspension settings, will probably start with moving only one of the two washers on the upper control arm and see how much negative camber I can get. Want to start at about 2 degrees negative and see what the tire wear is like. Hope to run the set up on the track and the street. May also corner balance with my 185 lbs in the drivers seat if I get really energetic! Hope to hear from others what their plans are!
 
Nice write up my plans are similar, I will be tracking at Calabogie if we ever get our cars, you didn't mention about lowering the car with z51 being easy to do (1" minimum I think), Cup 2's will be destroyed so fast thinking of other options, muffler is 75 lbs if you want to go delete, you going high wing also or standard Z51
 
I have a Z51 1LT mag ride coming....? I plan to track also but I am not good enough driver to appreciate the unsprung weight reduction. I wonder about going up in size on the tires. Do you know of anyone using these sizes on track already? I had tire rub issues in my C7 Z51 in stock size so I am reluctant to change sizing on the C8. I may just purchase an extra set of someones take off rims and use them for track. Anyone here selling their C8 Z51 rims? Also my big question at the moment is brake pads. Nothing other tan factory pads will work today. Any ideas on a track pad that works with the C8 brake monitor system? I also plan on an alignment Camber -2 front and -1.5 rear as I will not change the alignment for street too.
 
Nice write up my plans are similar, I will be tracking at Calabogie if we ever get our cars, you didn't mention about lowering the car with z51 being easy to do (1" minimum I think), Cup 2's will be destroyed so fast thinking of other options, muffler is 75 lbs if you want to go delete, you going high wing also or standard Z5
 
Lots of great info. I have a 2015 Z51 M7. The following is a list of weight reduction items I did for about a 100 lb drop;

ARH mid length headers with high flow cats
Borla catless x-pipe
B & B Bullet exhaust - the C8 exhaust weighs 76 lbs and the cats another 16 lbs
Innovator West light weight flywheel
Katech single mass light weight flywheel
DSS carbon driveshaft
LG GT coilovers
Halltech carbon cai
Removed AFM and NPP actuators
Braille light weight battery
MDS intake
Trunion upgrade
Removed some carpeting
Removed top fuel rail covers

Switching to AP brakes, forged wheels and non-runflat tires will save me about another 60 lbs. Sounds like your car will be awesome. Enjoy
 
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Thanks. Calabogie is really tough on tires. I will run mostly at Mosport (CTMP) but not averse to doing a Calabogie/Tremblant double header. Don't want to drop the car much.....maybe 1/2 inch as I will still want to drive on the street. Will see where it sits when the camber gets dialed in, then go from there. I like the Sport Cup 2's because they are great track tires and I can just move them from the left side to the right side to even out the wear and I can drive to and from the track with them. I am targeting 2000 track kms of life IF I can get the car set up right. Since I will be driving to and from the track, not many better options. Toyo R888R's have same sizes but heavier and not as "weather" tolerant a tire for the drives to and from the track. If I "adjust" the front sizing to 265/35/19 I can bring the Eagle F1 SuperCar 3R tires into play. A 1.9% increase in tire diameter, so probably will still not set the computer off. At some point, I will look at the exhaust system, as I am sure there is weight to be lost there. A simple titanium muffler, cat back system would probably do the trick, but will wait to see what the aftermarket brings. Probably do the 2 piece rotors first as it is unsprung weight. Will remove the stock rotors and pad, replace with 2 piece rotors and save the stock pads and rotors. Trying to keep everything else pretty stock as the car is new and I don't want to mess with it much. Best bang for the buck is always tires and wheels. Just need a car to put the plan into action!!!!
 
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Thanks. Calabogie is really tough on tires. I will run mostly at Mosport (CTMP) but not averse to doing a Calabogie/Tremblant double header. Don't want to drop the car much.....maybe 1/2 inch as I will still want to drive on the street. Will see where it sits when the camber gets dialed in, then go from there. I like the Sport Cup 2's because they are great track tires and I can just move them from the left side to the right side to even out the wear and I can drive to and from the track with them. I am targeting 2000 track kms of life IF I can get the car set up right. Since I will be driving to and from the track, not many better options. Toyo R888R's have same sizes but heavier and not as "weather" tolerant a tire for the drives to and from the track. If I "adjust" the front sizing to 265/35/19 I can bring the Eagle F1 SuperCar 3R tires into play. A 1.9% increase in tire diameter, so probably will still not set the computer off. At some point, I will look at the exhaust system, as I am sure there is weight to be lost there. A simple titanium muffler, cat back system would probably do the trick, but will wait to see what the aftermarket brings. Probably do the 2 piece rotors first as it is unsprung weight. Will remove the stock rotors and pad, replace with 2 piece rotors and save the stock pads and rotors. Trying to keep everything else pretty stock as the car is new and I don't want to mess with it much. Best bang for the buck is always tires and wheels. Just need a car to put the plan into action!!!!
I hope your right about the Cup2 but IMHO no way you will get anywhere close to 2000 km of track use from a set, I've seen them gone that fast on the street, see the 10 minute mark in the video shows they are destroyed after (3) 15 min. sessions in one day with the track settings


 
I hope your right about the Cup2 but IMHO no way you will get anywhere close to 2000 km of track use from a set, I've seen them gone that fast on the street, see the 10 minute mark in the video shows they are destroyed after (3) 15 min. sessions in one day with the track settings



Saw this video. Not normal to have tires gone after three sessions. Somethings not right. Sport Cups don't go away that quickly. After getting my Cayman S set up, I was able to get about 2000 track kms. on a set. Going a bit easy on them first session or two helps or if I can, I drive them around town before tracking them to sort of "heat cycle" them. Seems to help. I was down at about 800 track km until I got the car's set up dialed in better.
 
I have a Z51 1LT mag ride coming....? I plan to track also but I am not good enough driver to appreciate the unsprung weight reduction. I wonder about going up in size on the tires. Do you know of anyone using these sizes on track already? I had tire rub issues in my C7 Z51 in stock size so I am reluctant to change sizing on the C8. I may just purchase an extra set of someones take off rims and use them for track. Anyone here selling their C8 Z51 rims? Also my big question at the moment is brake pads. Nothing other tan factory pads will work today. Any ideas on a track pad that works with the C8 brake monitor system? I also plan on an alignment Camber -2 front and -1.5 rear as I will not change the alignment for street too.
Congrats on the car......hope it arrives sometime before the snow flies. Suggest that you track once with the stock tires and then you will have a baseline to compare any changes. I think you will find the difference "transformational" when you lose about 10 lbs per corner. Even just getting rid of the runflats should result in a noticeable improvement. No, I haven't heard about anybody using these sizes yet, but not sure the "trackies" have really go ahold of the cars yet. I would have moved to 18" rims, but not sure of the fit yet, but I suspect that they will and the aftermarket will come up with a good set of 18" rims for these cars. That will open up more tire choices and pricing should be better. If you can get take offs, that is great but you shouldn't run this tire size up front as you need a rim width of at least 9" instead of the stock 8.5". I have ordered rims with a 9.5" width for the front and 12" width rim for the rear. Since I am only adding a total of 20 mm tire width, both front and back, only really adding 10 mm to the outside and inside of the wheel assembly. I doubt that the factory left less than 10mm clearance anywhere and with the wheels being slightly small I am pretty confident it will be fine. If there is any rubbing, I suspect it will be very limited and only occurring during full lock parking lot maneuvers. I think there will be track pads available soon from the aftermarket. Will let them sort out any issues, but I don't think that it will be that big of a deal for the big brake players to figure it out.
 
Nice write up my plans are similar, I will be tracking at Calabogie if we ever get our cars, you didn't mention about lowering the car with z51 being easy to do (1" minimum I think), Cup 2's will be destroyed so fast thinking of other options, muffler is 75 lbs if you want to go delete, you going high wing also or standard Z51
Sorry, forgot to add........High wing ordered.
 
Saw this video. Not normal to have tires gone after three sessions. Somethings not right. Sport Cups don't go away that quickly. After getting my Cayman S set up, I was able to get about 2000 track kms. on a set. Going a bit easy on them first session or two helps or if I can, I drive them around town before tracking them to sort of "heat cycle" them. Seems to help. I was down at about 800 track km until I got the car's set up dialed in better.
Cayman S would be way easier on tires, 350 HP / 2900 lbs with low torque , the reason I'm thinking 888R's is because on the street they would be way more lethal than the Cup2 from a dig. 0-60 with 325 maybe 2.6/2.7
 
Cayman S would be way easier on tires, 350 HP / 2900 lbs with low torque , the reason I'm thinking 888R's is because on the street they would be way more lethal than the Cup2 from a dig. 0-60 with 325 maybe 2.6/2.7
I like the 888R's. Great track tire though I am not as comfortable in the wet with the 888R's as the Cup 2's. When the Cup 2's still have adequate tread left they actually have great grip in the wet, provided the water is not ponding. In terms of tire wear on the Cup 2's, I don't think that there will be too much of a difference between the Porsche and the C8. My PDK Cayman S is around 3000 lbs with 235's up front and 265's in back. With my 3400 lb C8, the C8 is about 13% heavier. With 265's up front, I will have added about 13% more tire width than the Cayman. With 325's in back I will have added about 23% more tire width than the Cayman. Assuming roughly the same F/R weight distribution for both cars AND IF I can get the suspension set up right, front tire wear should be about the same as the Cayman due to the proportional increase in tire width to compensate for the extra weight. With the same proportial adjustment plus an extra 10% in the rear tire width I am hopeful that this will compensate somewhat for the increased torque and give me about the same rear tire wear as the Cayman also. Unfortunately, all speculation and calculations until the rubber hits the road!
 
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If I remember correctly the C6 only had one part number for the front rotors as well, and they were directionally vaned. I recall the C7 also only has 1 PN, but they are not directionally vaned, so it doesn't matter. It'd be pretty silly if they made the same mistake on the C8. (Sorry, didn't watch the video, so perhaps it has the answer)
 
If I remember correctly the C6 only had one part number for the front rotors as well, and they were directionally vaned. I recall the C7 also only has 1 PN, but they are not directionally vaned, so it doesn't matter. It'd be pretty silly if they made the same mistake on the C8. (Sorry, didn't watch the video, so perhaps it has the answer)
I gotta figure GM could get something as simple as this right. In terms of brake pads, I think I will wait until Pagid, PFC, Hawk, Raybestos bring their high performance pads out before I commit. Stock pads until then.
 
Anyone tracking the car and looked at removal of the parking brake for track days? I think it is about 6 lbs each (unsprung weight) and if they are a simple electrical connection and a couple of bolts, it will be coming off at the same time as I install the rear brake ducts and change tires. Don't use the parking brake at the track anyway though I do wonder what computer nanny lights will light up!
 
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