Why No Bronco Cross Drilled/Slotted Rotors?

[Mikey]

I think if you guys tried cross drilled and slotted rotors on your Broncos you would be very pleased. I have a set on my 86 Capri and they work great! It would be cool if one of the big Bronco parts houses offered these. If you read articles on the benefits I think you would agree that a Bronco would be a great application.....great heat shedding ability, shortening braking distance and good water/mud throw-off capability. Also....they look really cool!!!

What do you guys think? Just a bit of extra machining to the stock rotors.....shouldn't cost too much more. My Capri's didn't.

Mikey

 

[edge4]

I have them on my 76'. I just wrote a tech article on installing them with the heavier duty Ford Thunderbird Calipers and 911 brake pads. They work great!
Broncograveyard sells the Powerstop rotors for the 76-77 Bronco.
Drilled Rotors

Edge

 

[76Broncofromhell]

Check JBG. I believe they offer them. If not, I know Raybestos offers them. I've driven cars with slotted rotors and drilled rotors and I didn't really notice a big difference on the street.

I venture to say that the reason most other Bronco owners haven't gone this route is the price. Why pay $80 per rotor when you can pay $25? I don't believe they will help in any situation except in heavy, sustained braking. The slots in the rotor allow the gasses to escape when the pad hits the rotor. Mud will have a hard time getting in a normal rotor but that relief could make it easier to get mud on the pad.

Here's the link, I believe these are Raybestos (they look like their performance brand from what I can tell)

http://broncograveyard.com/products/cat/13/33/12585XL

 

[76Broncofromhell]

Damn it, I type too slow

 

[MnkyBiz]

Will the drilled rotors work with a ford conversion, like the Duff's one? I haven't yet ordered my disc conversion, but the Duff's one is the most appealing so far!

 

[VT_Don]

rotors

Drilled rotors were originally necessary for out-gassing of organic pads. When hot from repeated or prolonged use, gas escaping from the pad prevented proper contact.
New generation, metallic pads do not emit gas. So, there is no need for holes or slots. The exception may be to eliminate every last ounce of unsprung weight. (Not an issue with goobers and thier 36" tires.)
I would even suggest that the holes are a liability. Their edges shave material from the pad. And, may act as stress risers. A hot, cast iron rotor making a stream crossing is not going to be happy.

 

[74bronc]

I am pretty sure I saw cross drilled rotors on jeepinc7 EB at the gathering in San Diego on Saturday. I made a mental note of them because I had never heard of anyone offering them for an EB. Might want to PM him and ask about them.

 

[Unregistered]

www.philsinc.com has them too.

I'm getting some for a chevy conversion soon.

 

[supermottl]

I put 4 new cross drilled rotors on my saab 9-3 DD. I will honestly say that I don't notice a difference in braking performance, and I drive that little 4 banger kinda hard on my 60+ mile/day commute. I surely wouldn't notice a difference in my EB

 

[edge4]

To respectfully disagree, I believe there is a difference.
With heavy 35+ tire set-ups, you have a huge rotational inertia built up at highway speeds. Second, with a lift kit your taller truck now puts almost all of its stopping power solely on the front brakes.
Most pads today are semi-metallic and are organic mixes. The cross drilled rotor will help with out-gassing and give the pad better contact with the rotor. They will also help reduce rotor temparature by 200deg. They will reduce brake fade and warpage of the rotor. Another benefit is better wet weather braking on your truck. The gold cadmium plating will reduce corrosion issues.
Yes, using the larger Thunderbird caliper probably made the bulk of the difference, but I will use everything possible if it can stop my Bronco quicker.
Edge

 

[72_EB]

I work for Phil's and can assest to their benefit and improved functionality over stock rotors. We've been selling them for many years now with great success. They cool better than stock rotors and therefore last longer PERIOD. The TRW/AUTOSPECIALTY Powerstop rotors are the brand we sell. Not cheap-o crossdrilled Taiwan/Chinese junk. One of our biggest markets is the Sport Utility/SUV market. We sell a ton of these rotors to folks that are warping stock rotor after stock rotor larger tires or running trailers. They do make a difference! If you want something even more elaborate, we can get into the big brake kits on a number of trucks also (Not the Early Bronco yet unfortunately, Edge is on the money with the Tbird upgrade. That is the only one I know of right now). But the Powerstop rotors are great deal for someone looking for a bolt on improvement at a lot less $ than a big brake upgrade. Again, Edge is right on with his comments on the benefits from what I have seen as well.

 

[VT_Don]

FYI

An interesting read. I think these people make brakes or something like that? Sorry if hot link does not work.
www.wilwood.com/faq.asp#question7

 

[Broncobowsher]

Let's see, spend more money on a part that is high maintance, using outdated technology to get that ricer image

Or just use ordanary parts that are cheaper and are known to work?

What should I do%)

 

[edge4]

Another interesting read. I guess each expert has their opinion.
I just know it stops better now than before.
TRW/Autospeciality Powerstop FYI
I will say that this is a pure street benefit. VT Don is right that mud will cause problems, if not cleaned properly.
VT Don, I may have been duped, but let me enjoy the bling factor for at least a week . ;D ;D

 

[supermottl]

Maybe you are right... I totally agree with what you are saying about rotational inertia and how much heavier 35" tires are, compared to a car. I would try them, but they are usually pricy for good set of rotors...

 

[Mikey]

Does the picture on the links show a "typical" rotor? It shows no hub. I never came across this on their website before.....oh yeah, it says it's new!

I had trouble with rotor warpage on my Capri so switched to the cross drilled and slotted. They work much better now.

Granted, the newer pad compounds REDUCE out-gassing but it still is not eliminated.

In the old days, cross drilled rotors would crack as the holes were too big and too close together. Now, they have this problem solved. They also use hole chamfering.

The newer hot sports cars are using them as OEM. They wouldn't spend the time and $$$ if they didn't work....I've worked as a design engineer...cost cutting is very important and the bean counters won't allow too much frivilty in engineering design. I'm sure the engineer sold the bean counter the fact he could use a smaller brake and sold the marketing dude on the coolness factor!

This has a great summary you have got to read:
http://www.avalonracing.net/rotors.htm

Try these for more info:
http://www.precisionbrakescompany.com/faq.html
http://www.precisionbrakescompany.com/power_stop_about.html
http://www.bendixbrakes.com/en_us/product/index.html
http://www.nationalfleetparts.com/rotors.asp

Thanks for all the comments,
Mikey

 

[iwlbcnu]

I ran Powerstop cross drilleds on my 85 stang and one cracked in 5k. I auto-x some but they should have lasted longer. Since then I have learned that unless road racing, stock is all that is needed. At the most go slotted. Cross drilled is still crack prone!

 

[Mikey]

Wow!

How long ago did you use those rotors? Were you running the 10 inch or the 11 inch rotors? What kind of pads? I converted to the 11 inch on my 86.

I bought a set of cross drilled and slotted rotors from iRotors.com who carry the Bendix brand and have had no problems driving in the mountains where many people routinely have to change warped rotors. I think I have about 6,000 miles so far. I also use the Bendix Titamnium Metallics (see the above links).

Mikey

 

[72_EB]

Mikey is right. Porsche uses crossdrilled rotors from the factory. Is a Porsche a Ricer? Don't think so. If all of us failed to embrace new technologies, we probably never would have seen fuel injected Broncos, progressive coil springs, hydroboost, electric lockers, etc. and all the new components that have made a mean machine even better!

But I've been over and over this whole debate for too long selling them. If you don't want better brakes you don't have to get them. Go to Autozone and buy some cheap-os disposable ones that you can replace when they warp. Is is your right to buy whatever you want. Cheap ones that you will replace sooner or crossdrilled that will perform better and last longer.

 

[74bronc]

I especially like the chrome plastic hub caps with the "cross drilled rotor" plastic thingy on the inside so that '84 Toyota Tercel blingers can look cool. I would love to put some of those bad boys on my Bronco!!