rjwoerheide

In the thread about the z51 badge it was mentioned that drilled brake rotors are inferior to solid or slotted ones. Is this the case? Isn't it true that drilled rotors stay cooler and therefore perform better in competition?

And if drilled rotors are inferior, why would the Z51 upgrade include worse brake rotors? I am confused by this and would love to hear some thoughts.

ken4hm

I don't know which is SUPERIOR... but my car stops real good with the holes in the rotors

C6NRED

You will get opinions on both sides of this........
There are very hot gases created at the point where the brake pad hits the rotor under hard braking. Slotted and/or cross drilled rotors are supposed to be able to vent these so that the rotors can stay cooler and therefor work better longer under severe conditions.
On the other side, you are diminishing the area on the face of the rotors, so the pads are not contacting as much surface as if the rotor was solid. Also, some of the aftermarket slotted/drilled rotors (the less expensive ones..) have had problems cracking and warping because the holes or slots were poorly drilled and the rotors end up not being balanced or working the way intended.

SilverFish

I think that's the main source of the problem. A lot of people drilled stock rotors and cracks appeared around the holes after a while. A rotor that was engineered for holes will stand up better. I have had no problems with my Z51 cross drilled rotors and I have nearly 22k miles on them. I am however on a new set of tires though...Nitro Invo.

FloydSummerOf68

The drilled rotors have a larger diameter and make up for the space that is lost from the drilling.

Typically two rotors of the same size; one being drilled and one being solid, will result in the solid rotor having better stopping power.

The problem, as mentioned, is cracking.

ThunderWheels

I have heard the same about the cracking. But I think it probably a poorly engineered rotor or aftermarkets. 27k on mine and no problem. Plus, have you seen the big honking drilled rotors on the ZR1? Yeah I know, different material but those withsatnd up to 1000 degrees and no warping. Plus they will out stop the Carrera GT 0-100-0.

Pocket Aces

The brake diameter probably has much more impact than anything else so bigger brakes with some holes or slots would be way better than smaller solid brakes by far.

moolys

push

When my stock rotors are gone I'll either be upgrading to the z06 setup, or rocking slotted.

rjwoerheide

So the increased diameter makes up for the loss of surface area, and the holes keep the rotors cooler. Ergo Z51 rotors > base solid rotors. Makes sense to me!

Mark VerMurlen

You should ask this question in the autocross & road racing section of the forum. Any of the Corvette brake packages are more than enough for average driving on public roads. Its when you start doing driver ed. days on a track that you'll start to stress your brake system.

I have experience with track days with my old C5 with solid rotors for which my front rotors would last 4-6 track days before they would crack. I don't have any experience yet with my new C6 with Z51 rotors. I'm sure that those in the road racing section can tell you what their experience is.

- Mark

AutoCutter

Holes and slots are to increase the surface cooling area as well as allowing the pad off gases to escape giving better pad contact. Holed and slotted rotors have to be properly drilled (or better yet cast formed), but the rotor needs to be seasoned. It has been my experience that holed and or slotted rotors give better braking performance from both stopping distance and pad wear. Where I see problems with holed and slotted rotors is that they cost alot more than solids and if you race a lot, solids can be a cheaper solution given the quick wear from racing.

spares

im in no way an educated car techy but FWIW just knowing of high performance sports cars and race cars more often than not you get drilled and or slotted brakes, therefore evidence points to them being superior

BigJoe

You also have to consider the source of the original comment. Anything Z51 related has to be, by definition, the same as or worse than the same part on a base Vette according to OregonC6... "toetap:

OregonC6

You must have missed that I always mention that the Z51 rear sway bar is always reported to improve performance over the smaller diameter base item. It is clearly superior.

As posts on this thread have noted drilled rotors that are somewhat larger ( like Z51 and F55 ) may have the same surface area as smaller undrilled ones.

I recall reading technical reports comparing style of brake rotor that said that the reason for the holes , that is to allow out gas generated from the pad to escape and not buffer the pad to rotor contact, is now mostly unneeded due to different pad composition.

I am familiar with reports that the Z51 option results in faster 1/4 mile times by a small margin. This is attributed to the gearing difference in the manual cars only. What I don't recall seeing are reports that compare stopping performance base vs Z51/F55. This would be interesting.

There is much technical information available on the websites of aftermarket rotor/brake suppliers. Of particular note is the two part rotors that weigh much less than the solid stock ones.

Also, reading from numerous forums and technical sites I have seen the opinion expressed by people who should know that the holes in any brake rotor today are mostly for show as this "style" has become something like the huge wings you will see on Civics and Preludes etc etc.

As for Z51 option equipment being inferior to the base car I don't recall hearing of cracked solid rotors-only drilled. Also, I recall reading that the Z51 option tires wear out very fast AND under certain circumstances can be dangerous. These circumstances are cold and wet road conditions. The tires, as I understand them, are designed for warm/hot track conditions so if that's what you have they are superior.

I have also consistently said that I think the Z51 option is priced low if you want the tires that come with it. You get the closer manual ratio, the sway bar, tires, and , for some, bragging rights that are way beyond what the option delivers.

I suggest that you go to aftermarket brake rotor suppliers websites and avail yourself of their view of drilled vs solid vs slotted vs two piece etc. From what I've read from those who track their Z51 optioned cars and Z06s many eventually "upgrade" to aftermarket brakes.

You have to ask yourself at that point, if drilled rotors make the Z51 optioned car and Z06 more track worthy, why owners convert them to other styles? Use search and you'll find photos of cracked drilled rotors pretty easy to locate.

rjwoerheide

Thanks for the thorough response OregonC6. I appreciate hearing your thoughts on this, especially as it was your comment that made me curious

danl72

crazyeddie

I bought a tube of Hole-be-gone, sold by many of the fine Forum Sponsors and I'm here to tell you that the holes are now gone. I bought the stuff on a group purchase for only 199 dollars, not including shipping of course. The only problem now is most folks think that I have a base Corvette, but I'm buying some badges from another fine Forum Sponsor for just a little under 100 dollars.
I'm sorry for thiseddie

Rob Willis

Unless your beating the heck outta them at HPDE or driving schools, the Z51 rotors are fine for 98% of normal drivers.

At the track, slotted or solid are normally preferred.

2006c6keller

This quite funny that you have to "season" the rotors. You can really "season" them easily and warp them by having VERY HOT DRY BRAKES and run through a big water puddle; boy, will that warp them.