[GrabTheWheel]

I ran with a C6 ZR1 this weekend at Laguna Seca and the owner managed to fit 18 inch Forgestar F14 wheels over his enormous carbon ceramic brakes. Not sure of the exact rotor size but it looked at least as big as the rotors on the ZL1. He was running Toyo R888R 295 fronts and 335 rears. The setup supposedly cost $1400 for the wheels and and about a $1000 for the tires. Seems too good to be true, especially since I just paid $1800 for a set of 20 inch Cup 2's that are already towards the end of their life.

Also curious for those of you running track pads like Gloc how many days are you getting out of your pads and how often are you replacing rotors? I will most likely need to swap rotors before my current set of pads are finished. What are my options? And what is the best way to tell if the rotors are toast?

[Can'tHave2MuchHP]

Certain wheel companies make 18” that fit over the Carbon Ceramics of Z07s and ZR1s. Nothing new. I’d expect to spend $3000 on Forgestars + tires. Maybe less. His numbers are correct. And his sizing is good but no where near what a ZL1 could run.

I think the carbon ceramics are bigger, therefore some 18” should fit our ZL1’s rotors but it won’t be your run of the mill 18”. They’ll have to be by a company who knows what they’re doing. I know Forgeline does an 18” setup that fits.

[chicagosam]

2009 ZR1
Front 15.5"
Rear 15"

2017 ZL1
Front 15.35"
Rear 14.4"

Be carefeul with 18's. Do your homework on the wheels you pick, the barrel, offset and the way the spokes angle will determine if your calipers will fit. I screwed up on my 18's on my wilwood equipped 67 firebird. The calipers hit the back of the spokes.

Or just go 19's, plenty of tire sizes to pick from.

[Zl1+911]

I would like to know the definitive answer here as well, as 18 are likely to be lighter and cheaper tires.

[FlowForm_Wheels]

Originally Posted by GrabTheWheel

I ran with a C6 ZR1 this weekend at Laguna Seca and the owner managed to fit 18 inch Forgestar F14 wheels over his enormous carbon ceramic brakes. Not sure of the exact rotor size but it looked at least as big as the rotors on the ZL1. He was running Toyo R888R 295 fronts and 335 rears. The setup supposedly cost $1400 for the wheels and and about a $1000 for the tires. Seems too good to be true, especially since I just paid $1800 for a set of 20 inch Cup 2's that are already towards the end of their life.

Also curious for those of you running track pads like Gloc how many days are you getting out of your pads and how often are you replacing rotors? I will most likely need to swap rotors before my current set of pads are finished. What are my options? And what is the best way to tell if the rotors are toast?

We make a 19" Wheel for the Porsche GT3 with PCCB's, and before you ignore this comment because I'm talking about another car, think about the tight clearance between the caliper and the inside part of the barrel. Our clearance on the GT3 is very tight, so tight that rocks and other debris can get stuck on the caliper. Doesn't sound like a big deal until you realize the rock is stuck between the caliper and the inner barrel of the wheel, and if you think about it while the wheel is rotating, you're probably now visualizing that rock etching into the barrel yeah? It does happen, don't think that the smallest diameter wheels are going to give you the most benefit.

Based on what we see here, we recommend 19"s for track use. Brakes are huge on this car anyway so a 19" is going to accommodate it better with less issues overall.

[Can'tHave2MuchHP]

Originally Posted by Zl1+911

I would like to know the definitive answer here as well, as 18 are likely to be lighter and cheaper tires.

The definitive answer is that you can get 18” wheels that will fit. But it’s not going to be some 18” off of a minivan. A high quality wheel company will make them slim enough in the spoke and barrel as to allow clearance for the caliper/rotor. Call up your favorite wheel brand and I guarantee they’ll make you a set or recommend a set that already fits. Like I said I know Forgestar, Forgeline, and how others make them for the larger Carbon Ceramic Corvette brakes. The only issue you may run into is a limit on width before it rubs.

Personally I have no idea why you’d want to go too small and risk damage. Stick with 20” or 19” for a brake this big.

[chicagosam]

Originally Posted by Can'tHave2MuchHP

But it’s not going to be some 18” off of a minivan.

My minivan rolls on 19s. You best roll up on me with at least that.

[cwebster]

Originally Posted by GrabTheWheel

I ran with a C6 ZR1 this weekend at Laguna Seca and the owner managed to fit 18 inch Forgestar F14 wheels over his enormous carbon ceramic brakes. Not sure of the exact rotor size but it looked at least as big as the rotors on the ZL1. He was running Toyo R888R 295 fronts and 335 rears. The setup supposedly cost $1400 for the wheels and and about a $1000 for the tires. Seems too good to be true, especially since I just paid $1800 for a set of 20 inch Cup 2's that are already towards the end of their life.

Also curious for those of you running track pads like Gloc how many days are you getting out of your pads and how often are you replacing rotors? I will most likely need to swap rotors before my current set of pads are finished. What are my options? And what is the best way to tell if the rotors are toast?

I think the key here is to ask for "high" pad clearance. This parameter causes the wheel to be constructed with a wider inside diameter where the caliper rides. Looking at the wheel off the car you'd see a sort-of channel where the caliper would be.

You can see a raised "hump" between the rims in the photo of my BC Forged wheels (2nd one down) here: New Wheels

You can see the channel more clearly in the 3rd & 4th photos of the original post in this thread: Installed BC Forged Rims & MT DRs The 6th and 10th photos (installed side views) in that same post show there's a lot of extra clearance there. I just now measured the inside diameter of my BC Forged wheels at the mating surface of the wheel and rotor (the high clearance channel) to be 17 1/4". If you measure the radius from hub center to outer edge of front wheel caliper and double it you'll can tell whether BC Forged 18's would fit.Too dark to measure the front caliper radius on mine now.

I was only buying rear wheels for drag racing at the time so I didn't compare to the front. I've been considering buying a full set of BC Forged wheels for road track racing but I was going to go with 20's. You could ask Paul Alkhasian of PK Auto Design whether other ZL1 owners have used similar wheels. I really like the BC Forged wheel styles and color options. I chose the 18x12 RS40-14 style with 43mm offset and "high" pad clearance for the drag wheels but I was thinking 20x11 front and rear for the track wheels. The only negative I had was the relatively long lead time. They're custom forged so they say expect 5-weeks plus shipping. I let Paul put my wheels and tires together for me. He even installed the GM TPMS sensors that I had shipped to him from the dealer - saved me a lot of time and headaches.

--Cal

[WEAPON-X]

We can easily do 18" Forgelines and have a track pack for purchase! I can do an 18x11 square with a spacer on the front or 18x11 and 18x12 trued up.

ZL1 is 2A for square and 2B for true on the drop down! If you guys want tires/tpms shipped to your door, we can add that as well!

https://weaponxmotorsports.com/produ...l1-1le-lt1-lt4

[Chris Edwards]

Originally Posted by WEAPON-X

We can easily do 18" Forgelines and have a track pack for purchase! I can do an 18x11 square with a spacer on the front or 18x11 and 18x12 trued up.

ZL1 is 2A for square and 2B for true on the drop down! If you guys want tires/tpms shipped to your door, we can add that as well!

https://weaponxmotorsports.com/produ...l1-1le-lt1-lt4

Anyone done an 18” GA3 on a ZL1 yet?

[MaumaroZL1]

Originally Posted by WEAPON-X

We can easily do 18" Forgelines and have a track pack for purchase! I can do an 18x11 square with a spacer on the front or 18x11 and 18x12 trued up.

ZL1 is 2A for square and 2B for true on the drop down! If you guys want tires/tpms shipped to your door, we can add that as well!

https://weaponxmotorsports.com/produ...l1-1le-lt1-lt4

I wonder what are the full dimensions on the 18x11 with 18x12 rear Forgelines they are using? I would love to swap my stock GYs and wheels out for a dedicated winter tire/wheel combo (and not using $orgelines) but people seem to be all over the place on caliper-rotor-rim spacing recommendations for the ZL1. One of the other vendors on here brought a good point about things getting stuck between rotor and rim when the spacing is too little. For a DD wheel/tire combo the idea of that happening rubs me the wrong way <of course no pun intended lol>

[SgtRick]

Originally Posted by GrabTheWheel

I ran with a C6 ZR1 this weekend at Laguna Seca and the owner managed to fit 18 inch Forgestar F14 wheels over his enormous carbon ceramic brakes. Not sure of the exact rotor size but it looked at least as big as the rotors on the ZL1. He was running Toyo R888R 295 fronts and 335 rears. The setup supposedly cost $1400 for the wheels and and about a $1000 for the tires. Seems too good to be true, especially since I just paid $1800 for a set of 20 inch Cup 2's that are already towards the end of their life.

Also curious for those of you running track pads like Gloc how many days are you getting out of your pads and how often are you replacing rotors? I will most likely need to swap rotors before my current set of pads are finished. What are my options? And what is the best way to tell if the rotors are toast?

I ran 18" Forgestar F14 whells with MT drag radials on my 2010 ZR1. No problem. I only made three 1/4 mile passes on the tires and wheels. Just sold them for $1000. I paid $375 for each wheel and the tires were around $300 each. I sold the ZR1 for the 2019 ZL1.