The Speed Chief

Will cross drilled rotors survive 2-3 HPDE events per year, with Carbotech pads?

I have a C6 Z51 that I use on the street, and for HPDE events. I know most people go for maximum on track performance with a solid blank rotor, but I really enjoy the look of the cross drilled rotor. And I don't always have the time to change out rotors and pads.

So, I was thinking about using cross drilled rotors for the street and track, and just replacing them once per year (or as needed). Will they survive on track? Are they guaranteed to crack?

I am moderate speed in the intermediate group, with Carbotech XP10s and XP8s.

If it really makes more sense, I could just buy solid rotors and swap each time...

Ryan

Mark@AMT Motorsport

Depends how fast you go and what kind of rotors. If you buy the cheapest rotors you can get, well, I'd get about 3 hours out of them till they cracked and that was just a plain rotor. A drilled rotor would not even last that long. So if you spend a couple hundred bucks on a quality drilled rotor, you might get 6 days out of them if you're a casual HPDE'ist.

rabrooks

Most likely not. The rears will last about twice as long. The fronts are going to crack somewhere in the second event if you brake fairly hard and your events are two day events.

But it's hard to say as each person is different.

cagotzmann

For how many years ?

My experience from Spring Mountain Ron Fellows performance schools using the C6 Grandsports or the C7 Z51 Cars (Hawk HPS Pads which are similar to Carbotech) the rotors did very well for more than 2-3 HPDE Events. eg

day 2 ,6 sessions 20 minutes each.
day 3 ,6 sessions 20 minutes each.

When I asked how often they changed rotors , "it depends on the students" but these cars are only used at the track.

SunnydayDILYSI

Dimpled rotors are a good way to get the cross drilled look with reliability closer to a blank.

rbl

If you can trash them in 3 hrs then you have bigger issues.

C6 Z51 OEM rotors are considerably thicker than others and more meat on the back side as well. They will EASILY last several HPDE events with good pads. I ran them for several years and they will develop small cracks around the holes but not even close to a crack requiring change.

I never had one failure with them and we did about 15 2 day events annually.

Mark@AMT Motorsport

You're right I missed the Z51 part. My experience was with the stock sized C5/C6 rotors, though I can't imagine the slightly larger Z51 rotors would last exponentially longer.

jaredtxrx

Bah, reread your initial post. Disregard.

Adam@Amp'dAutosport.com

You should have no issue as long as you buy a QUALITY rotor.

LateBreak

Is the look of holes in your rotors really so important that you're debating on whether to run something that you already know is subpar in performance? That might be a rhetorical question, I'm just a bit dumbfounded....

TorontoC6

You should be able to get at least 4 days from stock Z51 rotors. Depends on track - some tracks are harder on brakes than others. I ran a 2006 Z51 for 4 years and averaged almost 6 days for a set of rotors.

One thing that will increase the life span is good cooling. Get some spindle ducts and feed them with Z06 brake ducts taking cold air from the front. That should almost double the life span of your rotors (as long as you let them cool down before parking).

EdsC6Z06

I ran my OE cross drilled rotors for a while before noticing the cracks forming between the holes. Lots of guys just run cheap rotors and keep spares to swap if cracks form. Expensive rotors can crack too. I'm currently running Girodisc rotors with Carbotech pads. Been pretty good after about 4 events with 3-4 sessions per event. Some micro-cracks in the fronts but otherwise holding up. Rears look new.

The Speed Chief

If anyone knows these tracks in particular - how do you think cross drilled rotors would do on Road America and Blackhawk Farms, with a C6 Z51 and Carbotech XP 10/8's? Reasonable, or for sure going to be an issue after 2-3 days of HPDE?

I am working on setting up brake cooling now.

Aardwolf

I normally use blanks but I had some of those rotors awhile back on a different combo. I'm trying to remember and I think there were 2-3 track weekends on these before the cracks. I run Road America and BHF. On my car I found over heating problems at Blackhawk compared to RA. Much much more heat!

TKOGTO

If you have cooling, the rotors will last quite a bit more than 2-3 days. If you don't, they'll still make it thru many more than 2-3 days. The rears will last about twice as long. I ran drilled OEM rotors when I 1st started for at least 12 days. Plenty of heat checking but they did not crack.

Make sure to do a cool lap and/or drive around the paddock for a couple minutes after each session. When I have cracked rotors, it was right after parking without a sufficient cool down.

fizzer07

I know this will horrify some here, but I run carbotech xp10 and xp8 with cheap *** rotors from advance auto parts, like $120/ pair. They have a 2 year warranty, so I return them yearly for exchange. I've done it twice for the fronts and once for the rears. I run 2-4 weekends per year at the track. They will generally last at least one year before developing cracks ( not just heat checks- those develop in one weekend).
I figure even expensive ones crack so why not get cheapos?

KNSBrakes

Sometimes it ends worse than others.<br/><br/>

rabrooks

Keep in mind the car behind you that his grill will receive your discharged parts
You get no brakes and he gets a new radiator you paid for. lol

Hopefully no one gets hurt.

KNSBrakes

The Z51 has pretty large rotors - and depending on your track use may not heat up/down quite like some others or some other applications so they may in fact last 'long enough'.

My real issue with cheaper rotors or drilled rotors or especially cheaper drilled rotors is the inconsistency of the material and what drilling can do to it. It's a casting rather than a billet or forged part so mechanical properties can vary and perhaps widely.

I think that can lead to more unpredictable or more catastrophic failure and if that can be avoided or minimized I'd say it's worthwhile.

rkdc5z06

it will survive if you dont use brakes much, but basically depends on how much torture they go through.