Drilled or Slotted?

[ho1ywars]

whats the deal, i hear people bashing both.. i hear bs about both.
drilled keeps the rotors cool, and slotted keeps the pads clean right / fresh, but wears them down? slotting doesnt cool the rotor does it?

[xEJ20x]

Slotted.

[DropTopChevy]

Go big or go home but if you dont have that choice id say drilled. They use it on the new vette and that thing stops on a dime, but its also fiberglass.

[2000MRDC2]

id say slotted I heard some **** about drilled cracking the rotors because it puts stress on the small areas between the holes

[xEJ20x]

id say slotted I heard some **** about drilled cracking the rotors because it puts stress on the small areas between the holes

I've actually heard of the drilled cracking due from heavy braking in the rain.

[ho1ywars]

id say slotted I heard some **** about drilled cracking the rotors because it puts stress on the small areas between the holes

yeah thats what i heard. but i hear slotted rotors just act like a razor, and eat through pads.

[ITSTOCK]

Drilled rotors make less of a surface and are also more prone to cracking.

I haven't heard of ANY downfalls of a slotted rotor. If you look at the REAL race cars, they are usually solid (not slotted OR drilled, but some or slotted). It's just the point that there is more surface area which allows for more stopping power and better heat dissapation.

For a street car, I really don't think it matters.

The simple facts point to the idea that the blank/smooth or the slotted rotors are the ONLY way to go.

Cross drilled AND slotted rotors suck. My brother tried brembo and baers on his car, BOTH sets ended up cracking 1 rotor.

[ITSTOCK]

Go big or go home but if you dont have that choice id say drilled. They use it on the new vette and that thing stops on a dime, but its also fiberglass.

:bigeek:

lol, well if they use it on the vette, it must be the best! In all honesty, a lot of the "drilling" is all bling baby! They look good, but don't help with performance.

[ho1ywars]

:bigeek:

lol, well if they use it on the vette, it must be the best! In all honesty, a lot of the "drilling" is all bling baby! They look good, but don't help with performance.

porshe and mercedes use them to, just drilled. im not trying to start any trouble here, just want to here everyones opinions.

[ITSTOCK]

porshe and mercedes use them to, just drilled. im not trying to start any trouble here, just want to here everyones opinions.

Same with ferarri.

I'm giving you facts, it's not really opinion :wink:

Another fact is, they look BLING (if I were buying a $160,000 car I would want something looking nice behind those rims also!) :banana:

[LSHatch]

Like you said, you can't beat a large, solid rotor.

The slots/holes/whatever help cooling a little bit, but take a lot of strength away from the rotor. Take your wheels, put a bunch of little holes in them, see how strong they are then.

[xEJ20x]

Like you said, you can't beat a large, solid rotor.

The slots/holes/whatever help cooling a little bit, but take a lot of strength away from the rotor. Take your wheels, put a bunch of little holes in them, see how strong they are then.

Those are called "Speed Holes", they make the car teh fastAr! :finga:

[MuddyREX]

I have slotted front rotors and my pads have lasted almost 60K, so I haven't noticed any increased wear. I also didn't notice any better performance between the slotted rotors and the stock ones. Wasted money IMO.

[LSHatch]

If your pads have lasted 60k, that explains a lot. Slotted rotors won't have any affect on a car that is not driven hard.

You won't notice much of a difference anyways. The biggest difference to be noticed is through new lines, fluid, and pads.

[MuddyREX]

If your pads have lasted 60k, that explains a lot. Slotted rotors won't have any affect on a car that is not driven hard.

Funny you say that, being that you have never witnessed my driving style. I put 32,000 highway miles on my car last year.

[WrxJC]

I have slotted & dimpled EBC rotors and they work EXCELLENT. I'm a hard braker and i haven't worn out anything. I put them on a year ago, car was just inspected last month. They're good. AND they make this really cool cricket sound. :)

[LSHatch]

Funny you say that, being that you have never witnessed my driving style. I put 32,000 highway miles on my car last year.


Because the HIGHWAY is anywhere near track conditions.

Like I said, if you are getting 60k out of one set of pads, you aren't driving hard on them. That is FACT.

[Gorilla Unit 33]

good thread cause im looking to upgrade my rotors and pads within the next 2 weeks

[Raven18940]

My vote is for big, unsophisticated, vented rotors. My car has one piston brake calipers all around and 12 in. rotors up front. When I stamp on the pedal it'll damn near rip your face off. :)

[the mike]

I have slotted & dimpled EBC rotors and they work EXCELLENT. I'm a hard braker and i haven't worn out anything. I put them on a year ago, car was just inspected last month. They're good. AND they make this really cool cricket sound. :)


Same here.

[9 Ball]

If you do anything, go with slotted. “ITSTOCK” pretty much covered all the good points.

Drilled rotors are more prone to cracking. The drilled rotors on my Honda cracked and it’s no where near a speed demon.

[TehWagon]

i have slotted AND drilled- i'm in for it! :lol:

seriously though- i've had them on for a few months now, no probs so far, though i can see the theory in both the negative aspects... i'll keep you guys posted :wink:

[2point4DSM]

Slotted rotors won't have any affect on a car that is not driven hard. You won't notice much of a difference anyways. The biggest difference to be noticed is through new lines, fluid, and pads.

I have to disagree. Good pads makes the single largest difference on a stock setup. Going with bigger rotors, even if you keep the the OEM pads, is the only thing that beats it.

Unless your lines are worn and your fluid is boiling then drilled/slotted rotors comes next.

I got drilled rotors on my car because at one point I was in hurry and slotted rotors weren't available right away. Anyway, when I got the package I got a little note saying, "Sorry, one of your rotors is on B/O." So I ended up getting a stock rotor for one side to drive the car 300 miles the next day. After the pads were bedded/seated the car actually pulled to the one side under moderate braking, on the highway. So I ended up becoming a spectator that weekend.

Lesson learned.

Also, drilled rotors crack. Just like everyone else mentioned. Slotted rotors is the way to go. Good thing the type of driving I do doesn't require constant hard braking, lol.

Slotted rotors will wear your pads a little faster. But slotted rotors actually increase surface area, unlike previously mentioned. Not for pad contact though but more for cooling surface area. And the job of your brakes is to convert kinetic energy to heat. Better brakes are able to dissipate that heat better.

[ho1ywars]

good thread cause im looking to upgrade my rotors and pads within the next 2 weeks

me too, i was looking at drilled ebc rotors, but now am having second thoughts.

[LSHatch]

I have to disagree. Good pads makes the single largest difference on a stock setup. Going with bigger rotors, even if you keep the the OEM pads, is the only thing that beats it.

Unless your lines are worn and your fluid is boiling then drilled/slotted rotors comes next.




I said that pads make the biggest difference. But, before going and spending money on "bling" slotted/drilled rotors, just using a solid rotor with new pads/lines/fluid will outperform the slotted. This has been tested. As much as I hate magazines, one of them conducted a test on a WRX using all different types of brake kits. I believe stock rotors with new lines, pads, and fluid came in second place. Right behind the $3000 Brembo Gran Turismo. Not too shabby.

Under hard driving, any cars stock brake fluid will get hot and the brakes will fade.

For normal street driving, it doesn't really matter. If you want the car to look pretty, do what you want. If you are trying to set up a good track/street car, go with a better solid rotor and replace the more important things.

[slavetothemuzic]

If you want to avoid the cracking associated with drilling, you can opt for dimpled instead. My rotors are EBC slotted/dimpled rotors and I've had no issues with cracking at all.

[2point4DSM]

Under hard driving, any cars stock brake fluid will get hot and the brakes will fade.

Not necessarily true. I'm sure you can boil any brake fluid but Ford has an OEM brake fluid that is suppose to perform pretty well. I'm sure there are other OEM brake fluids that are pretty good, too.

Keep in mind dot 3 and 4 brake fluid is hrydroscopic meaning it absorbs moisture. And one of the biggest problems is that most people don't change their brake fluid often enough and the system starts to absorb too much moisture which then causes the boiling point to drop dramatically.

Standard Brake Fluid boiling points (degrees F):

Dot 3 (commonly used in OEM applications)
dry bp 401
wet bp 284

dot 4 (made with a different ester oil and has a higher boiling point. Most higher end cars come with dot 4 due to the fact that it is a bit more pricey.)
dry bp 446
wet bp 311

Dot 5 (slilicone based and it doesn't absorb moisture. But also INCOMPATIBLE with systems that are currently running Dot 3 or 4. Very pricey.)
dry bp 500
wet bp 356

Many people have recommended SUPER BlUE Racing. You can get it off ebay for ~11 bucks a quart. It's a DOT 4 with a boiling point of 536 (higher than dot 5).

Also, brake lines don't do all that much for stopping performance. It's role in the whole setup is brake feel. Since the line is more rigid you can modulate the brakes better. But I've never heard of people saying that it actually helps the car stop an X amount shorter. Consider that as long as the stock rubber lines are not ripped it is still possible to apply the same amount of force to the pads, even if takes a 2-3mm more of brake pedal travel to compensate for the lines expanding a little bit.

Sort of like running rubber IC hoses instead of metal ones. Sure the rubber hoses expand a little bit but your not losing boost compared to switching over to metal lines, as long as the rubber isn't ripped, lol.

[wgknestrick]

The point that most are missing with the porsches and merc having "drilled" rotors is a little misleading. These rotors indead have "holes" in them, but they are cast into the rotor, not drilled. This greatly reduces stress concentrations around the holes because of the fillets around the holes. Are they as resistant as solids, (probably not), but they don't crack like "drilled" rotors. Just drilling a set of solid rotors is not suggested by anyone who sees track time.

[ho1ywars]

The point that most are missing with the porsches and merc having "drilled" rotors is a little misleading. These rotors indead have "holes" in them, but they are cast into the rotor, not drilled. This greatly reduces stress concentrations around the holes because of the fillets around the holes. Are they as resistant as solids, (probably not), but they don't crack like "drilled" rotors. Just drilling a set of solid rotors is not suggested by anyone who sees track time.
good call, i didnt know that.

[2Mopars1Ford]

According to the Hawk rep that came in our store slotted and drilled rotors were good when brake pads were inferior and vented alot of hot gases during use.
However brake pads (at least the better ones) have evolved to the point where not as much gases are created and slotted/cross drilled rotors make minimal differance.

[2point4DSM]

According to the Hawk rep that came in our store slotted and drilled rotors were good when brake pads were inferior and vented alot of hot gases during use.
However brake pads (at least the better ones) have evolved to the point where not as much gases are created and slotted/cross drilled rotors make minimal differance.

I've been running Porterfield R4S on my car and when I tried running drilled on one side and stock on the other side and it made a noticeable difference on my car.

A lot of people consider the Porterfields to be one of the best pads around along with Hawks.

[htheduck]

(Try Porterfield R4 and your slots will be gone in two days :eek: ...all depends on the weight of your car.) Hawk and Porterfield both make good compounds. However Hawk makes a few more pads with higher heat range choices than the R4. Both are good choices.

As for the original topic of this thread: go slotted or stock oe rotor if you are on the track-(unless you go BBK then that's a whole new ballgame). Since you're on the track you are usually using squeaky race pads - which will eat rotors no matter what. (Holes in rotors-as mentioned in posts before are for bling and good marketing)

As for fade-I've faded with the ATE super blue (a little)- and comtemplating if I need a higher temp fluid. I've faded the stock fluid in my SRT4 but on a different set of pads. I'm still trying to determine if some pad makes absorb more heat than others.