Yes.....

WRONG!

No-one has said this and they won't......

This whole thing stems from someone noticing the rotors being the same on both sides and the pad wear issues for hardcore trackers and racers....

No need to get this blown out of proportion...

 

I'll admit its a non issue on any car that doesn't see track time, but they took the time to put a rear diff cooler and a dry sump oiling system on the 06 and they can't get the rotors right?

The car is supposed to be track ready right off the lot, instead the brakes are just driveway jewelry. I'd rather them have made the vanes straight/non-directional than have one rotor on there backwards.

 

Nobody said that....the car will brake on both sides, it just that cooling will be **** poor on the pass side, leading to premature rotor fatigue and cracking, premature pad wear, increased brake fade, etc.

I don't think its going to cause you to lose control per se, but its certainly not a desireable outcome for a $70,000 supercar.

 

Look at the rotor vane direction on the pictures in this thread....post #132 the yellow Brembos swirl counterclockwise (toward the front on the driver's side) while the Motive, post $137 do just the opposite....so who's right? Does it truly make a nickel's worth of difference?

http://forums.corvetteforum.com/show...e+part+numbers

 

No, real race cars don't use them because they stop slower than blanks. Cross drilled is a marketing gimmick. Porsche engineers have stated that the only reason they have them is because their consumers demand them. Same with the Corvettes I am sure.

http://www.ls1tech.com/forums/showthread.php?t=353903

 

well doug... allow me to learn a bit...

if the reason for cross drilled rottors is to reduce heat... and by using them backwards, they accually build up heat, thus getting hotter...

so while one side is accually cooling down, the other side is heating up...

the brakes would be less effective wouldnt they? because they are hotter...

soo... because brakes on one side are being less effective, thus giving a loss of control...

probably the only problem with this philosophy is that brake rotors get up to 2thousand degrees anyway...
but the only reason disc brakes work is because they convert the kinetic energy into heat... yet, when the brakes hit the max temperature, they become uneffective at converting kinetic energy to heat... but thats whats nice about ceramic pads is that they change temperatures so quickly...

 

Good question. Fbod vented rotors were "straight" vents and so it didn't matter. I'm going to hazard a guess that if it does matter and you put a directional on backward, the shape of the rotor wants to move air from outside to the hub which is backwards from how the air is supposed to move through the rotor. The again you could be onto something and it makes no difference, I never really thought about it.

 

The drill holes don't do squat. It is the vanes/vents that cool the disk.

 

I'm pretty sure whatever direction the vanes are designed the point, they need ot be consistant on both sides.. as in the rotors, on whatever direction the vanes point, should not be simply flipped and run in reverse.


Honestly, for a car as important and high visibility as this, GM has to step up and do two things. Replace every Z06 rotor with the correct directional rotor. Then make sure there is at least plentify supply of pads, so the people tracking their cars aren't left out cold without replacement pads.


GM doesn't want to get stung with another "half a'sd execution" perception. Come on, its a $70k car that they hvae been touting as the high performance track star.

 

They actually make it worse because 1-it takes away mass, meaning there's less rotor there to store heat, and 2-they cause stress fracture and heat risers.

Cross drilling is 100% bling, nothing more.

 

If it makes no difference then why do directional vane rotors exist at all?

GM Cheaped out, end of story. Will 90% of the owners know the difference? No, but 90% don't need the magnesium roof & engine cradle or dry sump oiling system or 505 hp LS7 either. Whether we will notice is not the point.

 

My guess is that some engineer found a few degrees of difference up at around 1k deg+++ and thought, hey why not? The "fan effect" is just a bonus....but possibly more effective than direction. I'd guess the extra mass of longer vanes in the directional rotors helps a tiny bit too.

Until someone can find the actual engineering data that shows that it truly makes an appreciable difference, I ain't losing any sleep over it.

My guess again, GM couldn't support the extra cost with real data and chose to spend their efforts elsewhere......the cooling of brakes is helped 1000X more by GM's efforts at brake ducting.

 

The performance gain was minimal when compared to the cost.

 

Well, again Doug, then why not just cast 1 rotor PN# with straight vanes, at least that way both sides are equal rather than the potential for a temp differential. The ducting on the pass. side isn't going to do much good if the rotor is pumping air opposite of the duct.

It would seem uber obvious to me, granted I'm not a bean counter or an engineer, just a lowly consumer, that if separate L and R rotors were cost prohibitive, then maybe we should stick to a uni-directional rotor. DUH!!

 

so rotate your pads!