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Department of Weights and Measures

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SCGT500 said:
Anyone know a close weight of a stock rotor versus a 2 piece rotor on a S550 or GT350?

Just wondering what type weight saving there is for that crazy money. Lol


...and with that, I recieved a couple spare GT Performance Pack rotors today.... 35 lbs each!!!!!

Crazy :(

Front 2 piece GT350 rotors are 30 lbs; Rears 18 lbs
 
Black Boss said:
Front 2 piece GT350 rotors are 30 lbs; Rears 18 lbs
Updated first post. That's 5 lbs heavier than the Boss front. I don't remember weighing a rear. Does anyone know what they weigh?

The front rotors must be a lot thicker than the rears. That's pretty interesting, but good since we could have used more mass on the front Boss rotors. They should hold up to the heat better.
 
8250RPM said:
I received my FORGELINE 11x19 GA1R open lugs with Michelin pilot sport cup 2 305/30ZR19 today.
The weights are.
Fronts 49.100 pounds
Rears 47.950 pounds
Thanks. Does anyone have the actual weights of the wheels?
 
cloud9 said:
Updated first post. That's 5 lbs heavier than the Boss front. I don't remember weighing a rear. Does anyone know what they weigh?
Than the stock Boss rotor? The GT350 rotors are significantly larger. I still think a Stoptech or Girodisc two piece will save a couple of pounds vs the stock rotors, maybe more. I'm also curious if the drilled rotors will crack at the holes.
 
VoodooBOSS said:
Than the stock Boss rotor? The GT350 rotors are significantly larger. I still think a Stoptech or Girodisc two piece will save a couple of pounds vs the stock rotors, maybe more. I'm also curious if the drilled rotors will crack at the holes.
Yes. Stock Boss front rotors are 25 lbs. To be honest I'm not looking for a lightweight alternative to the GT350 rotors. I'm looking for better heat dissipation and durability. That takes mass.
 
Black Boss said:
Front 2 piece GT350 rotors are 30 lbs; Rears 18 lbs

Thanks.

Though 5 lbs of rotating mass is somewhat significant, at $1000 a pair not worth it for a few weekends a year of track time. :(
 
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cloud9 said:
Updated first post. That's 5 lbs heavier than the Boss front. I don't remember weighing a rear. Does anyone know what they weigh?

The front rotors must be a lot thicker than the rears. That's pretty interesting, but good since we could have used more mass on the front Boss rotors. They should hold up to the heat better.

Thicker yes, in terms of the hub/ring ratio. The rear rotor has a larger hub (im guessing for the parking brake+weight savings) so much less steel on the rear rotor.
 

ArizonaBOSS

Because racecar.
Moderator
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Arizona, USA
On the brake rotor bit--the 15" Brembo Pro kit that is on the IMSA 350R-C cars and clears 18" wheels uses two-piece rotor assemblies that are 18lbs in the front.
 
ArizonaBOSS said:
On the brake rotor bit--the 15" Brembo Pro kit that is on the IMSA 350R-C cars and clears 18" wheels uses two-piece rotor assemblies that are 18lbs in the front.
Iron rings?? What are replacement rotor (ring) costs?
 

ArizonaBOSS

Because racecar.
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Arizona, USA
cloud9 said:
Iron rings?? What are replacement rotor (ring) costs?

Yes, iron rings w/ aluminum hats. Replacement ring cost around $375-500 per side depending on if you use StopTech or Brembo, respectively (interchangeable, as I'm told). That is for the 35mm thick, 72-vane rotors.
 

Bill Pemberton

0ld Ford Automotive Racing Terror
8,424
8,349
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
Let's see, weighed 170 lbs 5 years ago , now am at 210, so car is not here and I have about 4 months to get rid of 40 pounds of unsightly Faaaaatttt ! Still won't be down to Slim Stud Gaspar's poundage , but it is a start.

1. +1 , would be able to get back into my racing suit ( $ savings )
2. +$50 bucks a month eating less junk food ( can spend on parts)
3. + $50 bucks a month on less beer
4. - $50 bucks of fun as no beer
5. +200 -$400 to spend on parts to help the car lose more weight if I achieve the goal.

Let the games begin!
 

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