Anyone using cross drilled rotors???

[bskylerj]

I was wondering if anyone is using crossed drilled roorts on the front of your truck? I have a 71 Chyenne Super with discs and would like to get some cross drilled rotors for it. Where is the best place to buy and what kind of price did you pay? I have drop spindles on it so I do not want to change them out to run these. Mine is the 5 bolt pattern. Thanks for the help.

[Longhorn Man]

I have not run slotted nor cross drilled rotors, so this is second hand info, however, keep in mind, the average drilled rotors like to crack between teh holes. I've seen plenty come in to the shop like that, and these are on heavy pick ups and suburbans and the like. The DO help, but they are a one time use rotor, as they can not be turned (to my knowledsg...I know WE can't turn them, we damaged out machine learning this).

[bskylerj]

Thanks Longhorn Man. I have heard that also but like the look of them as this year my truck is going to be mostly for show. I could also get away with the slotted rotors. I have not heard many bad things about them. Have you?

[N2TRUX]

You can do a Google search and gets tons of info. Let me give some of my experience. I know cross drilled rotors look cool. I plan to run them on my 82 Blazer, but they are not vey practical. They do tend to stress crack, but this can be prevented if you have them cryogenic treated before you run them.

They "can" be resurfaced (turned) if you have a brake lathe with the proper cutting bit. The common style of cutting bit is pointed and tends to chatter. If you use a cutting bit that is "bull nose" or rounded and go slow it will turn them just fine.

Another big controversial issue about cross drilled rotors is the amount of swept surface you loose. In high performance or racing applications the benefits of the cooling effect outweighs the surface lost from drilling. In most applications the rotors are larger than stock as well, so you actually have more surface area.

In average driving use or applications where the rotor size has not been increased cross drilling becomes a trade off. You have the cool look but you do loose some braking performance by having less surface area.

If you want the best of both worlds consider using slotted rotors instead of cross drilled. Since slotted rotors have machined slots in them that do not go completely through, they "almost never" suffer from stress cracking. If they are cryogenic treated they are very durable.

Slotted rotors also offer the advantage of running cooler as well as pulling trapped gases away from the pad that causes them to float on the rotor. They can be turned on a lathe with a conventonial bit as well. You do have to make smaller cuts until you get a smooth surface.

Just my .02 based on my experience...let the flaming begin...

[Longhorn Man]

Good info there.

We have a truck at the shop that is notorious for crappy brakes. the bosse's rig, 99 k1500 blazer. (old body stye). The brakes on that, with all new stuff, properly adjusted, bled, new EVERYTHING sucked to say the least. He got some rotors that are both drilled, and slotted, stock sized. I was thinking he wasted his money, but I have to say, they helped quite a bit. IMO, they still feel like crap, however, it will stop much quicker and with less panic from the driver.

If the truck is more of a show thing, then just call up NAPA or whomever you want to get your rotors from, and do it up.

[71SWBChevy]

It is recommended for street applications to only go slotted due to the fact that drilled will crack between holes easily. If you look at the racing scene none of the major racers are still using drilled rotors, they are now going with dimpled rotors which won't crack like drilled but still leave places for gas to escape to.

[Longhorn Man]

Some of the high end ones won't crack, but my understanding is they cost more than anyone is willing to pay.
But I have no first hand info on that though.

[bskylerj]

Thanks for the info. This is why I wanted to ask you guys. The Napa's do not carry any slotted rotors for my truck. They have a stock style rotor with the grove in it. I would like the extra stopping power as my big block with the supercharger is pushing close to 700 horsepower. I think I will go with the slotted ones.