Brakes

[Unreal]

 

New coleman rotors and carbotech XP8 pads are here. Should be a nice upgrade, and took a ton of weight off the front. 

[SLAMMER]

I have been using 2 pcs. Colman rotors on the front only for 2 1/2 years. I just ordered new rings for the front and 2 pcs. rotors

including top hats for parking brake. I'm happy with the Colman rotors. I've used both Carbotec Bobcat (street)

and 10's & 12's for track days. Be sure to get as much air on those front rotors to keep them cool. 

SLAMMER

[Unreal]

Not cooling them at all. Not concerned either. 

[MidNiteFury01]

How much weight was removed?

[Guest badbobs95]

13 hours ago, SLAMMER said:

I have been using 2 pcs. Colman rotors on the front only for 2 1/2 years. I just ordered new rings for the front and 2 pcs. rotors

including top hats for parking brake. I'm happy with the Colman rotors. I've used both Carbotec Bobcat (street)

and 10's & 12's for track days. Be sure to get as much air on those front rotors to keep them cool. 

SLAMMER

WOW! You just sounded so intelligent, I"m impressed. Or did Donna write this stuff for you?  It's pick on Tim day.

[Unreal]

About 30lbs off the front of rotating weight.

[HOXXOH]

If you don't plan on them getting hot by extreme use and weight was important, then you could have dropped off a bunch more weight by using C6 base brakes (JL9) where the rotating weight is even closer to the axis. And you could have done it for a ton less money in the process. Stopping distance with base brakes and 1521 pads is shorter than OEM J56 brakes anyway.

 

However, as an appearance mod (aka not intended for track use) the Coleman's do look pretty cool.

[Bigfoot]

Looks sweet...although the surrounding dirty mess looks terrible.  

[MidNiteFury01]

4 hours ago, Unreal said:

About 30lbs off the front of rotating weight.

 

Interesting. An OEM Z06 Rotor weighs ~26lbs, removal of 30lbs (give or take 1/2lbs @ max for changes in pad mass x 2 calipers), would result in a two-piece rotor wieght of 10.5lbs each? Are you using the 325mm or 355mm rotors? 

 

Are you more concerned with acceleration rather than deceleration where there is ample runaway space such as 1/4 or 1/2 mile events? Loss of the mass is nice, but mass is your friend to a point where thermal capacitance is of utmost importance such as converting kinetic energy to thermal energy . Rotor mass dictates the ability to absorb and dissipate heat and thus the functional performance longevity. Just curious.

[Unreal]

Yep, only concerned with being able to stop once from 1/4 or 1/2 mile, then sit. Not over and over again. These are MORE than enough.

 

They do offer a HD outer ring which weighs a bit more and is thicker.

 

No idea on size. Whatever OEM is.

 

 

[MidNiteFury01]

probably the 355 if they are stock Z06 size. do you run skinny's up front to save even more wieght?

[Ted Y]

Did you consider a carbon rotor like the ZR1? 

[Unreal]

Yes skinnys up front.

 

Hell no on carbon rotors. They are same weight, and 6x the cost, and everyone I know who seriously races them swaps to iron anyways. 

 

And that is rotors alone, pads and calipers also have to be swapped, and that is stupid expensive too. 

[HOXXOH]

4 hours ago, MidNiteFury01 said:

 

Interesting. An OEM Z06 Rotor weighs ~26lbs, removal of 30lbs (give or take 1/2lbs @ max for changes in pad mass x 2 calipers), would result in a two-piece rotor wieght of 10.5lbs each? Are you using the 325mm or 355mm rotors? 

 

Are you more concerned with acceleration rather than deceleration where there is ample runaway space such as 1/4 or 1/2 mile events? Loss of the mass is nice, but mass is your friend to a point where thermal capacitance is of utmost importance such as converting kinetic energy to thermal energy . Rotor mass dictates the ability to absorb and dissipate heat and thus the functional performance longevity. Just curious.

 

The Coleman 355mm rotors weigh 16.25 each vs 26.5 for OEM, so it's close to 20 lbs total. OEM base (JL9) rotors are 18.75 each, but the calipers are nearly 4 lbs lighter and the 325mm keeps the weight closer to the axis. Of course, then you do the rears so the F/R balance is correct and save another 7+ lbs per side plus the rotational diameter bonus. Total OEM Z06 (J56) vs OEM base (JL9) weight difference is ~38 lbs not counting pad differences. Most of the more serious straight line racers go the base route, which also allows GTO spare wheels and B&M bias skinnies without the need for spacers. As you might notice, I'm very weight conscious, even to the point of using open end lugnuts to save another 1.2 lbs.

BTW, the base rotors are uni-directional and the cooling is from interior to exterior. The J55 rotors (aka Z51 or F55) not only have correct rotation on one side and not the other, but the rear's airflow is from outside to inside, which really looks funny with the duct trying to push air into the non-existant rotor inlet. 

One road track guy I talked to a few years back, uses base rotors and very aggressive pads. He said he goes through rotors about every third race day, but the rotors were purchased with a lifetime guarantee, so he just takes them back for free replacements. 

[MidNiteFury01]

3 hours ago, HOXXOH said:

 

The Coleman 355mm rotors weigh 16.25 each vs 26.5 for OEM, so it's close to 20 lbs total. OEM base (JL9) rotors are 18.75 each, but the calipers are nearly 4 lbs lighter and the 325mm keeps the weight closer to the axis. Of course, then you do the rears so the F/R balance is correct and save another 7+ lbs per side plus the rotational diameter bonus. Total OEM Z06 (J56) vs OEM base (JL9) weight difference is ~38 lbs not counting pad differences. Most of the more serious straight line racers go the base route, which also allows GTO spare wheels and B&M bias skinnies without the need for spacers. As you might notice, I'm very weight conscious, even to the point of using open end lugnuts to save another 1.2 lbs.

BTW, the base rotors are uni-directional and the cooling is from interior to exterior. The J55 rotors (aka Z51 or F55) not only have correct rotation on one side and not the other, but the rear's airflow is from outside to inside, which really looks funny with the duct trying to push air into the non-existant rotor inlet. 

One road track guy I talked to a few years back, uses base rotors and very aggressive pads. He said he goes through rotors about every third race day, but the rotors were purchased with a lifetime guarantee, so he just takes them back for free replacements. 

 

Great information. In college we ran F-Body Mustangs and we did everything possible to lighten the car and induce weight transfer to the rear (mind you we were college students with limited budgets) upon acceleration. To assist with lightening do you remove the passenger seat, remove windshield washer fluid (8.5#'s), etc.? You might find this post helpful if you've not researched it yourself;

 

http://www.corvetteforum.com/forums/c6-z06-discussion/2711750-z06-oem-and-aftermarket-parts-weight-list.html

[Desertdawg]

18 hours ago, Unreal said:

Yep, only concerned with being able to stop once from 1/4 or 1/2 mile, then sit. Not over and over again.

 

 

 

When I did the 1/2 mile, I ran 3 consecutive runs with waiting in line each time. I turned my stock z51 fronts blue. Be careful with cooling time between runs. 

 

[Guest Mikey]

My secret way to reduce the weight is to always "take a good poop".  TMI?

[TheCMSH]

See kids, this is a lesson on how to get a new tagline  

[HOXXOH]

17 hours ago, MidNiteFury01 said:

 

Great information. In college we ran F-Body Mustangs and we did everything possible to lighten the car and induce weight transfer to the rear (mind you we were college students with limited budgets) upon acceleration. To assist with lightening do you remove the passenger seat, remove windshield washer fluid (8.5#'s), etc.? You might find this post helpful if you've not researched it yourself;

 

http://www.corvetteforum.com/forums/c6-z06-discussion/2711750-z06-oem-and-aftermarket-parts-weight-list.html

 

Yes, that's a great thread. I have my own weight list of parts for a base car.

When I'm halfway serious, both seats are out (use a 26# race seat), I run 21# Hoosiers on 20# A-molds on back and 13# M&H bias skinnies on 13# GTO spares on front and less than 1/4 tank of gas. Check WW fluid shows up on the DIC daily, so I should probably add an ounce or two next month maybe.

 

When I get serious, I'm about 200# lighter than a bare bones Z06.

 

[Unreal]

I wanted to stay with z06 brakes to keep stopping power up. That is why I didn't go base brakes. Almost same weight, but got a much larger rotor and better caliper, plus when daily I'll enjoy the bigger brakes. 

[HOXXOH]

On 1/9/2016 at 11:59 PM, MidNiteFury01 said:

 

Great information. In college we ran F-Body Mustangs and we did everything possible to lighten the car and induce weight transfer to the rear (mind you we were college students with limited budgets) upon acceleration. To assist with lightening do you remove the passenger seat, remove windshield washer fluid (8.5#'s), etc.? You might find this post helpful if you've not researched it yourself;

 

http://www.corvetteforum.com/forums/c6-z06-discussion/2711750-z06-oem-and-aftermarket-parts-weight-list.html

 

Here's another thread discussing brakes, stopping distances, large vs stock, and ZR1 vs Z06 vs F55 vs Z51 vs base.

It's far less about size than it is about tires, pads, the amount of weight you're trying to stop, and if it's once or repetitively.

Brakes and tires are both places where bigger is not always better.

http://www.corvetteforum.com/forums/c6-corvette-general-discussion/2312444-stopping-distances.html

[MidNiteFury01]

Thanks for the link.  Good references. There's a lot of truth to the matter in the importance of tires. Not only do they allow for acceleration they also stop the vehicle. Brakes simply turn mechanical energy to thermal energy, thus creating wheel torque, but its the tires which stop the car.