I've heard drilled and slotted rotors crack more than non drilled.
What are the advantages of drilled rotors over non-drilled, are they worth the extra $$?
What are the advantages of non-drilled over drilled?
Thanks.

If you believe what the dudes on the weekend car TV shows say, the drilled and slotted rotors are much better at expelling "gasses" during the braking process and these rotors are more effective. I have never heard anybody say anything about them being more prone to cracking.

Since I think you are referring to your track car, the TV guys also point out there are many brake pad compounds from pure street to pure track (for instance, EBC's Blue Stuff, Yellow Stuff, Green Stuff, Red Stuff).

Drilled Rotors are fine for street cars.... The issue supposedly comes in when cars are being tracked with the constant extreme heat cycles weaken and they crack easier. Since there is less surface area.

Thank you.
I've read a pile of articles since I posted the question. Some seem to be results of research others someones opinion without facts to back them up. I think I've sifted through most of the BS.
It seems gassing off the old style pads was the reason they first went to drilled rotors, now with metallic and semi-metallic pads it's no longer a problem. Even NASCAR is getting away from drilled rotors although they still use slotted. They also change the brakes after a days driving.

Then there's the formulas of how much energy it takes to heat a pound of steel compared to a pound of air, the coefficient of friction in X material compared to Y material Blah blah. They all seem to agree about the cracking problems though.

When I took my front suspension off this week I was surprised to find the left rotor and pads grooved. I measured the rotor and the depth of the damage, to lathe off the rotor past the damage it will end up thinner than minimum, I'll have to buy new. The drilled ones look nicer but I'll save the money and buy stock replacements.

I turned and drilled my stock rotors for my 97 chevy 1500 and 96 grand am. The reason was to reduce warping from heat build up. The grand am rotors lasted quite a while before warping. The ones on my truck are still not warped, even after several years and est 50k miles

I used a Bridgeport machine with adapter plate with degrees on it
I have not had cracking issues even after this long. Both cars are daily drivers

I think what happens is the drilled hole end up being a weak spot in the surface. I have seen rotors with crack radiating out from drilled holes. Never seen any damage or associated problems with slots. If you want more cooling of the rotor/pads/calipers/wheel bearings, I would vent some air directly onto the rotor. That's what I did after having an extreme overheat of one side on a track day. Easy enough to do.

Yeah the air ducts seem to be the way to cool things.
Man if I had one of those Bridgeport milling machines I could have saved a lot of $$ while building my engine.
A far as truck brakes, I've had my 86 F250 for 25 years and 300,000 miles. still have the original rotors. While going down a mountain pass with my sawmill behind, I got the brakes so hot the grease started to melt out of the bearings. The rotors are still good. although my heart is a bit weaker.

It was cheaper for me to buy a kit than get what I needed separately. I got an MBM DBK6472 complete from the hard lines down with non-drilled rotors
It took me two days to install as once again I ran into aftermarket lack of quality control:
The inner bearings would not fit on the spindles, I had to take off about 0.0004" from the spindle;
The outer bearings would not go on over the lip left on the spindle from cutting the keyway;
The rear steering arm attach bolt was too short;
The front steering arm attach bolt was too long and made contact with the anti-sway bar end link;
The cotter pin holes in the spindle were drilled too near the end, I had to double up the keyed washers to get the pin to go through a castlation in the nut;
The cotter pin holes were not counter drilled, a sharp edge stripped the threads on one nut, I dressed out the spindles and used an old nut;
The holes in the splash plates were not of the correct shape, they made contact with the control arms. I used a die grinder to modify the holes;
The worst was the caliper brackets, they are so misshapen I couldn't get the pads between the bracket and the disc. A ball peen hamer, aluminium drift and an 18" cresent wrench massaged the brackets into shape. If the don't work I may have to take the things apart for the umpteen time and put the old brackets back on;
The new dust caps would not fit in the rotors;
The pads are ground in an arc shape, I don't know if that was by design or not;
The hoses are too long.

But there's good news! It quit raining today, I wont get wet going over to the big island to have two root canals done.

Welcome to my world
When guys buy these kits and drop off the car for me to install they question why it takes so long to install.

WOW! My complete kit from Master Power Brakes was awesome. Not one fitment issue.

Now getting it delivered via UPS was a nightmare. They kept laying the kits on their sides (long flat boxes labled LAY FLAT in large print) and the parts would tumble onto one another in transit. My only save was that between the 1st two damaged kits, I managed to piece together 1 undamaged kit (due to LH and RH parts).

Well so much for good news, it rained (at least it's not snow) and the first $350 is consulting fee, the root canals start tomorrow.

I got back from the big island and convinced my wife if she operated the brake pedal, I'd get the brakes bled and the car out of HER garage and into it's bird house tonight. I ran a quart of fluid through and it still goes right to the floor on first depression, I can pump it up but after a couple min. it 's back to the floor. I've done a lot of brakes in my time but this one's got me baffled. No air left that I can tell, there was still fluid in the master cylinder before I started so no air there. FTH? It has a proportioning valve under the master but no brake light on.


UPS sent my tranny from Vancouver to Nanaimo and back six time and failed to get it to Pender island each time. I finally picked it up at their depot, box broken open and parts missing and damaged.

Upon further inspection it is not a proportioning valve but a pressure differential switch. I am going to repost this as a bleed question.

Bigchief, do you run a service garage?