: Drill and slotted rotors?



Lawrence_C
03-18-08, 08:03 PM
Anyone here got drill and slotted rotors on their catera? I was just browsing through ebay and see quiet a bit and wonder if they would make any more of an impact besides looks. I have heard bad stories about poorly made ones warping.

cateraowner
03-18-08, 08:21 PM
well it's like poorly made regular rotors they will warp. but with slotted ones there is less surface area, so you can imagine if it's poor quality it'll be more proned to warping.

slotted is made mostly for racing to cool the rotor better.. so every day driving all you'll notice is louder and it can chew your pads faster

the only reason I'd ever consider them is purely for looks. it would look great with racing mags and painted calipers..

Lawrence_C
03-18-08, 08:46 PM
the only reason I'd ever consider them is purely for looks. it would look great with racing mags and painted calipers..

yea, that's why i was considering them also

Brosepe
03-18-08, 09:35 PM
I have EBC Slotted and Dimpled Rotors with EBC Green Pads. When I first got them it took me awhile to get used to them. I was stopping at least a car length sooner at lights. My friends hated me because it became more fun to slow down than to speed up. Instead of running yellow lights I would come to sudden stops. I need to order a new set. I got them almost 2 years ago from the tirerack.com.

elvin315
03-19-08, 06:25 AM
Slotted and cross-drilled discs are very popular these days. Slotted discs literally have slots across the surface, while cross-drilled discs have holes drilled through them. In the old days when the brakes would get too hot they would vaporize pad material. The pads would ride this plasma gas trapped between them and the disc surfaces, seriously reducing braking.

To release this gas racers began drilling holes in the brake discs, but that led to cracking as the discs expanded and contracted from the extreme heat generated. Slotting reduces the chances of cracking. Now there's something called dimpling. These are partially drilled holes that, like slots, don't fully penetrate the discs. Dimples provide the benefits of holes but without the risk of fractures.

These "performance discs" also provide a safety and performance advantage in wet weather. Brakes donít work well after driving through a puddle because water gets between the brake pads and the discs. With performance discs the brake pads act like squeegees and push the water into the holes & slots that channel the water away.

Street cars don't generate the heat that race cars do but that doesn't mean they can't benefit from performance discs. Shorter braking distances in wet or dry conditions always a good thing. Despite those benefits, I suspect that because brake discs show through many popular wheel designs, people buy performance discs for that racy look.


These are the ones I'm using. They're dimpled and slotted so hopefully they won't fracture. I chose black anodized for the look. It wears off the swept area with braking but the dimples and slots remain black (actually dark grey). Also using ceramic pads. Supposedly they produce less brake dust but I wash the car often so its hard to tell if that's true. So far the stops feel shorter but without actual testing I'm only guessing. What's most definitely better is braking in the rain. Gone is that "F@#K, no brakes" moment before they dried enough to to grip.

click
http://brakeperformance.com/site/images/pic-rotor-sd.jpg (http://brakeperformance.com/site/brake_rotors.php?vtype=1&vmake=2495&vmodel=2531&vyear=2544&vdetail=2545&cPath=1_2495_2531_2544_2545_2546&ad=google)

Elvin

CateraMV6
03-19-08, 08:40 AM
Elvin that is some great educational info here, you guys better be taking nots.

On another note I would like to add some more info to that.
Sloted or dimped or even drilled rotors WILL NOT!!! improve your braking in any way... if you look at what stops your car, its the swept area of the rotor and the clamping force of the caliper, also add to that the diameter and weight of the wheel... so with that said by reducing the swept area of the rotor via the dimples or slots you are actually using less area to create the same friction.

So in order to improve braking you need to increase the frictional area of the rotor or make the rotor a larger diameter and that will reduce the moment arm created between the face of the tire and the caliper. You can also reduce the tire weight or diameter to lower that value.

Another thing you can do is use some more grippy pads which will also increase friction and improve your braking. Now if you cant do any of those, you can always increase the area of the pad by a larger caliper.
The caliper itself can provide more clamping force if you you go lets say a dual piston instead of the single on in our OEMs.
The last thing you can do is increase the Vacuum booster and that will give you more clamping force as well....

So pick one..

Increase Rotor Diameter...
Increase Rotor Swept area.
Increase Pad size.
Increase Friction by better pad material... (Racing Pads)
Increase Clamping force by caliper via:
- Larger Caliper.
- Larger Master Cylinder/Vacuum Booster.
Reduce Wheel weight.
Reduce Wheel Diameter.

So far I have experimented wtih a few of these.

Lighter wheels help just about everything, braking accelaration, steering etc.
Smaller Tiar Diameter improves accelaration as well as braking but causes higher RPMs and lower Top End SPeed...
Larger Caliper improved braking, not by much but enough to notice.

I personally think these are the easiest ones to upgrade and get the best improvements...

sccatera97
03-19-08, 10:06 PM
As you can see, the opinions of the slotted and cross drilled rotors are varied. You can make a good arguement either way. I have them and I like them but does it really help? Anything was better than 4 warped rotors I had. Do you research and decide from there.

Army_MP_From_MO
03-22-08, 11:07 PM
I was thinking about getting the dimpled and slotted rotors, but now I'm not sure. What types of brake pads have the kind of "grippy pads" would everyone recommend?

CateraMV6
03-23-08, 03:19 AM
Well the Hawk and there is another company out there HP or something like that, they make pads with a different type of compound that becomes very grippy once heated... so if you drive normally you are actually going to hate them but if you do some auto cross or track events then they might be nicer for you... just look around, Tirerack.com I think has some pads and they explain the different materials...

Army_MP_From_MO
03-23-08, 11:53 AM
Thanks for the info. I need something with excellent stopping power. Here in El Paso, everyone tailgates and cuts you off. I've never driven anywhere like this before!

elvin315
03-23-08, 03:41 PM
I've used EBC pads for years on my motorcycle, and now the Catera. I use the Red Stuff on the car. They're low dust ceramic & kelvar pads. Being low dust means that they're a hard compound so they took a long time to break in. Cold stops were longer than I expected. But now they grip hard cold or hot. I like them.

I use the Green Stuff pads on my bike. It's a Kawasaki Concours sport tour bike. It's heavy at 600 lbs not counting me and my belongings. No ABS so I don't want a compound that will lockup the tires. The Greens leave me plenty of cushion between when I apply the brakes and the chirps preceding lockup. They let me modulate the pressure.

I haven't tried the Yellow Stuff but I'm thinking about it. The Reds stop great but I can't help but wonder how they Yellows perform.

The Black Stuff pads are the standard replacements.


UD720 - EBC Ultimax Pad Set; Disc Pads; Front (General Replacement Pads)
DP2937 - EBC Greenstuff Street Sport; Disc Pads; Front (Spirited Street Driving)
DP3937C - EBC Redstuff Fast Street; Disc Pads; Front (Highly Tuned Cars and Fast Street)

Elvin

MaesMV6
05-06-08, 10:29 PM
dumb question here. whats the difference between vented and solid rotors? just wanna check before i order some and i get the wrong ones

CateraMV6
05-07-08, 12:10 AM
Well a vented rotors has vanes that run down under the braking surface to help with cooling and the solid ones are just solid hunks of metal... no internal cooling... you have to have the Sport version in order to get the vented rear brakes. THe regular cars all came with a solid rotor and the caliper is different too.
If you got a 99,00, or 01 sport chances are your car will have the vented rears if not then I would say they are solids...
Easiest thing to do is compare them to the front ones... if they look identical then they are vented...