QuiksilvrZ

I think my Z is just about ready for 4 tires, pads all around, and brake rotors up front, but I just got the car and it has a strange setup as it sits. I don't know the width of the wheels, but the rears are wearing 285/30/20 and the fronts have 275/30/19. Pilot Sport 1's all around. The rears look somewhat stretched and I hate it, so I'm guessing that they're 20x11. The front sidewalls are straight but the inner lip has a little bit of push, so I'm guessing 19x10. I'll post pictures tomorrow to help.

So far, my thinking was that I would get PSS's. 285/35/19 and 315/35/20, but I don't know how well that would work with TC, AH, ABS, etc. Another tire I looked at was the RS-3 Version 2. It appealed to me because it was supposedly designed for better wet traction. The vast majority of the car's time is on the street, so I need something that will work in the rain as well, so the regular RS-3 is out. I also noticed that the new Pilot Sport Cup 2 has sizes that could work...305/30/20 and 275/35/19. Very expensive though. I'm not sure I could justify $2000 for one set of tires.

I have no idea at all what rotors to look at. I'd only be changing the rotors, nothing to do with the calipers. Anything that will work with factory rotors and fit with a 19" HRE 543R wheel. Pad suggestions would also be appreciated.

rjwz28

The first tires you are looking at are too tall for the car. You do not want to exceed a 30 aspect ratio on a 315/20 for this car, and 25 is actually correct. The front should be wearing a 30 profile on a 19 unless you step down to a 255, which you aren't even considering. The 315/35-20 you mentioned for the rear comes in at a huge 2.7 inches taller than your factory rubber, 1.7-2.0 inches over factory C6Z06/ZR1 fitment and 1.5 inches over the gigantic 345/30-19s people minitub/flare their cars to run.

The Hankook R-S3 V2 doesn't come in appropriate sizes for your wheel combo, so that's out.

In the Michelin Pilot Super Sport line (their most current line of daily-drivable summer max performance tires), this translates to a 305/25ZR20 rear and a 275/30ZR19 front at $1474 plus shipping from Tire Rack. The Pilot Sport 2 is older and more expensive than the Super Sport, so forget about that. I'd definitely go with the PSS combo in your case

Adam@Amp'dAutosport.com

For a quality brake pad take a look at the Carbotech 1521 compound.

Carbotech™ Bobcat 1521™ The Carbotech Bobcat 1521™ is our high performance street compound that is our most successful compound. The Bobcat compound is known for its awesome release and modulation, along with unmatched rotor friendliness. Like our AX™ & XP™ line of compounds, Bobcat 1521™ is a Ceramic based friction material offering minimal rotor damage and non-corrosive dust. Bobcat 1521™ offers outstanding performance, even when cold, low dusting and low noise with an excellent initial bite. This compound’s virtually perfect linear torque production provides incredible braking force without ABS intervention. Bobcat 1521™ operating range starts out at ambient and goes up to 900°F. Bobcat 1521™ is suitable for ALL street cars, perfect for your tow vehicle, police cruiser. The Bobcat 1521™ compound has been found to last two-three times longer than OE pads you can purchase at a dealership or national retailer. That’s one of the beauties of Carbotech Ceramic brake compounds. Bobcat 1521™ is NOT recommended for any track use.

63Corvette

"In the Michelin Pilot Super Sport line (their most current line of daily-drivable summer max performance tires), this translates to a 305/25ZR20 rear and a 275/30ZR19 front at $1474 plus shipping from Tire Rack. The Pilot Sport 2 is older and more expensive than the Super Sport, so forget about that. I'd definitely go with the PSS combo in your case"

However, i would recommend the Stoptech Street performance pads for your application. Be sure to bed or burnish them properly.

QuiksilvrZ

I actually did some searching and found the height calculator and that the factory height ddifference was 0.8 inches in diameter. Do you think I could run a 275/35/19 and a 305/30/20? I believe that's a 0.6 inch difference. I'm hesitant to run a 25 in the rear

Bill Dearborn

Why do you want to change the brake rotors? Are they below minimum thickness?

Bill

QuiksilvrZ

They're super low, somewhere in the low 1 inch range last time I checked. Again, just bought the car. I only want to replace the fronts, and I thought maybe I could go bigger with the 19's? I don't know the offsets are though.

mkiv808

I would not go more than 18/19 on these cars.

19/20 is so much more unnecessary unsprung weight and our suspensions are not tuned to deal with rock-hard ultra low profile tires.

I guess if it's a street car and never tracked and you don't do spirited backroad driving it could be OK. If you care about performance, don't do it.

PSS's are fantastic tires, that said.

QuiksilvrZ

Like I said before, I just bought the car and it came with the wheels. I really do wish I had 18/19s but it is what it is and it'll be a while before I sell the wheels or get on the track. My main question is whether a 0.6 inch diameter difference between F and R will work with TC and AH since the factory difference is 0.8 inch. I think the sizes are 275/35ZR19 and 305/30ZR20 for the 0.6 difference.

racebum

as long as it's over .4 or .5" it works

problem with taller tires is they gear the car higher and slow you down via extra weight. you get taller gears and more lbs, also adds stress to wheel bearings and suspension bushings with that weight

so, would it work? yes

but a 25 series would be a more proper fit on a 305 rear. will look much more normal too. a 30 in a 20" wheel is a lot taller wheel/tire, may look odd on the car

rjwz28

You can certainly do it with absolutely no issues, I just am not recommending it. I bought my C5Z with 255/40-18F|295/35-19R and it looked and ran great, but you're looking at an additional +.5"R and over +.9"F with the setup you suggest. Remember, the 275/30-19F|305/25-20R setup is already .5" taller all around than the 265/40-17F|295/35-18R factory setup, and therefore doesn't actually give up that much sidewall (about a quarter inch between the wheel and the pavement) versus the 275/35-18F|305/30-19R that many people swap to.

Also:

QuiksilvrZ

Right you are, so here are some photos I've taken. It'd be very helpful if you could possibly confirm my thinking that my wheels are 19x10 and 20x11.






Front at 275/30ZR19. Doesn't seem too bad.





Front again.





Rear at 285/30ZR20. No clue why the previous owner chose this size, but I don't like this stretch.





Rear.

Also as mentioned before, all tires are Pilot Sport 1.

rjwz28

Given the stretch, I'd say that you are not far off with your size guesses. I believe my wheels displayed their sizes on the inside of the hubs (offsets were stamped back there for sure), so you can check to verify, but regardless, a 275/30-19 fits your fronts well and you can definitely accommodate another 20mm on your rears without any problems whatsoever, so my tire recommendation remains the same