4 Corner Winter Project

[Fully Vetted]

Dom, you've got 19" wheels to accommodate those big rotors, correct?

[XfireZ51]

Originally Posted by Fully Vetted

Dom, you've got 19" wheels to accommodate those big rotors, correct?

That's affirmative although the rears are only 13" rotors. The fronts are 14's and 18" wheels clear them and the calipers.

[Dynomite]

Originally Posted by XfireZ51

That's affirmative although the rears are only 13" rotors. The fronts are 14's and 18" wheels clear them and the calipers.

OK......on the Front you have 14 inch diameter rotors.
On the Rear you have 13 inch diameter rotors.

For the New Rotors........
1. What is the weight of the Front and Rear Rotors?
2. What is the weight of the Front and Rear tires including the rims?
3. What is the outside diameter of the Front and Rear Tires?

For the Old Rotors......
1. What is the weight of the Front and Rear Old Rotors?
2. I shall assume the same wheels (rims with tires) Before and After installation of New Rotors?

I shall assume you hit 120 mph in the quarter mile using old rotors and you want to know increase in horsepower available using lighter New Rotors?

The outside diameter of the wheels and top speed is to calculate the wheel/rotor angular acceleration (shall assume it is constant from 0 to 120 mph) in the quarter mile. It will be tricky to calculate the Moment of Inertia of the wheels but I shall assume most of the weight is concentrated toward the outer part of the tire itself. I shall also assume the Rotor weight is uniform from the center outward but in actuality the center separate hub is less weight. I shall (maybe) neglect the weight of the hub, bearings, wheel studs and bolts since such small diameter of hub.

I will also calculate the TOTAL Front and Rear Horsepower Savings on Asphalt in the quarter mile when going from the Old Rotors to the New Lighter Weight Rotors. See Item #2 for some initial Calculations Horsepower Losses from Angular Acceleration of Rotational Mass

I might also calculate the mass (moment of inertia) of the inertial DYNO Drum that would give you 10 horsepower savings (on the rear only) in the change to lighter rear total rotor mass even though the actually horsepower savings might be more or less in the quarter mile on asphalt.

[XfireZ51]

Nitto Invos

Front: 28lbs. 25.5"
Rear: 37.4 26.7"

Michelin SuperSports

Front: 28. 25.9" dia.
Rear: 35. 27.2"


OEM Rotors. OEM Rims

Front: 27.5. 25.8lbs.
Rear : 20 27.4

Performance A/FX

Front: 16.5
Rear : 14.5

Rear Axle: 3.73:1

Cliff,

I would also say that since these are 2 piece, the hub represents the majority of the weight savings.

[cvette98pacecar]

They look nice.

[XfireZ51]

Found a very interesting C&D article that was alongside the main topic of C7 Corvette Z51 v Shelby GT350. Forgetting for the moment, the topic of the main article, C&D looked at an interesting aspect of the GT350.
The Carbon Fiber Wheels that are available. They did some testing to see what the effect of 58lbs lower unsprung weight had on performance.
I have attached a pic of a table outlining this. You can see it in the Feb. edition of C&D pg. 18. Significant performance enhancement that I thought was relevant to the discussion at hand.

[XfireZ51]

[QUOTE=XfireZ51;236809]40d in Chicagoland today so took the opportunity to throw on new rotors. Offset is same as stock rotor so wheel fitment shouldn't change.

[WydGlydJim]

I've got Exotic muscle front calipers (brembo)...anyway, I bought a set of new front rotors, and the dang things rub on the calipers....first time I got down on them pretty good, the brakes actually seized, and the car would not roll until they cooled off...

So the guy at Exotic muscle just told me to start clearancing the calipers with a drimel tool.....seems like I shouldn't have to do this......anyone else ever have this problem, or hear of it....it also cause the rotors to warp, and I had to have them turned....I haven't braked hard since I clearanced them some more...makes me nervous....

[XfireZ51]

Jim,

These are Coleman rotors and as u can see from the pics, they identical with the stock rotors. Read several threads of Z06 drivers using these rotors w the Z06 calipers.

[XfireZ51]

Another "decent" day in Chicagoland today. Really looked like an early spring day. Lovely sunshine. Got the front fascia off and now the rear rotors are on.
Just need to torque the caliper bolts. Difference in weight for the rear rotors is not as dramatic as fronts.
Tomorrow is supposed to be a bit warmer so I will be putting on DRM brackets for rear trailing arms. Next weekend mount rear tires to wheels.