PeterM

The main reason for me to have the Coleman rotors installed on my 2009 was for the weight savings. The four rotors saved approximately 33 lbs of unsprung weight, which equals 198 lbs of body weight.

This savings in weight can be felt immediately upon driving the car (it's akin to removing a 198 pound passenger from the car).

I've also noticed that the car takes the rough spots in the road a lot easier and handling is more responsive. Now I'm really anxious for the Bilstein shocks from the group purchase to arrive.

I should also add that Daniel Finke from Finspeed gave me an incredible deal on the four rotors, and he is more than happy to share great advice.

I had the work done at Tirri Motors in Suffern, NY. My former Porsche tech now works there and he's also great with Corvettes. He's one of the few around these parts who actually takes the time to use a torque wrench correctly.


The stock "Anchor" next to the Coleman rotor.

DaOtherOne

They look good

Amol

Nice. What kinds of pads did you use?

PeterM

Hawk ceramics.

GMuffley

"Adding lightness"

Stingray23

I have the same exact rotors, and I also got them from Finspeed. Really nice people to deal with and a great price as well.

achilds

[QUOTE=PeterM;1577108368]The main reason for me to have the Coleman rotors installed on my 2009 was for the weight savings. The four rotors saved approximately 33 lbs of unsprung weight, which equals 198 lbs of body weight.

This savings in weight can be felt immediately upon driving the car (it's akin to removing a 198 pound passenger from the car).

I've also noticed that the car takes the rough spots in the road a lot easier and handling is more responsive. Now I'm really anxious for the Bilstein shocks from the group purchase to arrive.

I should also add that Daniel Finke from Finspeed gave me an incredible deal on the four rotors, and he is more than happy to share great advice.

I had the work done at Tirri Motors in Suffern, NY. My former Porsche tech now works there and he's also great with Corvettes. He's one of the few around these parts who actually takes the time to use a torque wrench correctly. QUOTE]

So you are saying reducing unsprung wt is a 6x reduction in sprung wt? How do you figure? I certainly understand the penalty for rotating wt, but that is a 2x difference as you pay for the rotation as well as the translation of the weight.

PeterM

[QUOTE=achilds;1577111103]For every 7-10lbs lost on any car you gain 1hp for sprung weight,

For unsprung weight (i.e. wheels or Rotors) the ratio is ~ 1:6, so 15 lbs lost ~ 90 lbs of sprung weight which is something like 9-13 HP increase. Another real benefit is the improved grip and wheel follow on rougher surfaces. Then look at it as a reduction in rotational mass...

I realize there are many opinions on this subject floating around the web, but I place my trust with an engineer friend of mine who builds crazy-fast cars without relying on tons of horsepower.

Crash_Z06

Looks great!

achilds

[QUOTE=PeterM;1577113152]I am not trying to start an arguement, I already stated you are claiming a 6:1 ratio so reiterating it doesn't explain it. The question was to provide the physics that explains the claim. Decreases in the unsprung wt will make the car handle better for sure. However let's consider what removing 100 lbs unsprung wt and using the 6:1 ratio would do: That would be equivalent to 600 lbs or 60 to 85 hp increase according to the above logic. That is huge and I don't think that is correct. Even the claim of 198 lbs leads one to equate 20 to 28 hp increase, again a pretty big increase. As far as the rotation wt reduction vs static wt reduction assuming the weight is all at the outer edge of the rotor (which isn't really true) then it would be a 2 to 1 savings. Again I'm not trying to start an inet war on this, but I am really interested in why your friend thinks this is true?

gtodoug

I don't know the physics behind this but I've heard that 6:1 number used tons of times over the years. The only difference I've seen is that as far as the hp is concerned you can only use that on the drive wheels.....so my understanding is that the weight lost off the drive wheels will register more hp. The majority of the weight savings on the rotors is off of the front rotors. IIRC it is only like 5 or 7lbs off each rear. So on the conservative side at 5lbs x2 sides a total of 10lbs or rotating weight or approx 60lbs or 6hp. Either weight it's less weight the motor is turning and putting more down to the rear wheels... Very cool!

bowtiguy

great product...I've been running mine for 3 years now. I get an entire season to season and 1/2 out of the fronts running Cobalt pads. still haven't replaced the rear discs.

Daniel will take of you too. two VERY good choices!

SS DNA

Those rotors look like high quality

DriverMod44

Do you know how much weight you lost from just the rear brakes. I currently have the fronts, that's why I ask.

Thanks

BillY2KFRC

Awesome, glad to hear your impressions about being able to actually feel the difference in handling. I will be installing mine (also ordered from Finspeed, great price!) in a couple weeks and can't wait to see how much more alive the car will feel.

BillY2KFRC

I think the savings for the rears is 6lbs per rotor.

Streetrod

So where are they made? (what town in China makes Coleman rotors?)

Wheels, rotors and what is next for us to sell out on?

They do look nice.

SR

DrtyHarry

Taking my car to Tirri Motors next week for tires, rotors (DBAs), pads, and lines. Never been there, but heard wonderful things about them. Their website looks like they have a super clean shop with some of the latest equipment. Thanks for pointing these guys out for me, Peter. They are 5 mins from me and I never knew it.

http://www.tirrimotorcars.com/equipment.html


Harry

NORTY

Do these replacement rotors use the OEM drum E-brake system?

tjd113

Nice Rotors been thinking about add them to My Z06, Note Coleman Rotors are made in the USA. Also you can get the rear Rotors with the packing brake or not they have two types of rear Rotors. Great post