slotted, drilled rotors, both or neither???

[Gomez]

What are your opinions on rotors? Slotted? Drilled? Slotted and drilled? Neither?

[rmoltis]

Well my last aspire I had drilled and slotted rotors.
And this current aspire. I went with just slotted rotors.
Both had ceramic pads.

Lemme compare them both.

The aspire with drilled and slotted rotors.
Whenever it was very wet and rainy out. They had good bite to them.
Because the water would be able to vent through the drilled holes.

Also on the highway at high speeds 105+ when I would jam on the breaks for a quick slowdown..
They would bite, then they would warm up quickly. And as it warmed up it would bite harder.
For example one time I was doing 100 racing with my gf at the time. We liked to play with each other.
Since her car had a 2.4l and mine had a 1.3.
Her car had more torque so got up to speed very quickly, but it had a limiter at 110. And would kick down to 100.
So I could hit 105 on flat grounds and hold speed and we were pretty matched once up to speed.

Well we were both racing one day on the freeway. And we were both maxed out.
And we started to pass an onramp. And I noticed a police officer next to me getting on.
I was doing 105 at least. So right as I'm lined up next to him. I slam on my brakes and within a second maybe 2 my Speedo dropped down to 60mph. And I was right on pace with the cop lookin normal.
There was no brake fade at all. It just gripped harder and harder as it warmed up.

But on a side note. In slow city driving where there wasn't enough braking to keep the pads and rotors warm.
My braking distance was increased so I would start slowing down earlier to get things warm.
The other option was slam on the brakes at every light causing them to rapidly heat up.

On another positive note. Keeping the brakes cooler made them last a very long period of time.
I think one pair of pads rotors lasted about 3 years. With at least 75k per year put on them.


Now this current aspire with slotted rotors.
I figured with slotted rotors they would stay warmer than drilled and slotted rotors.
Thus offering less reduced performance in city. As well as increased performance on highway.

They too have no brake fade from high speed slow downs.
And they too help dispell water through the slots on rainy days through the slots.
They offer slightly reduced in city performance compared to stock, but more than drilled and slots.
They offer better freeway performance compared to stock, but slightly less than drilled and slots.

And then stock pads are made to heat up very quickly even at low speeds for maximum braking all the time.
So they have excellent stopping power at low speeds.
And they have great stopping power at high speed... That is until brake fade sets in from outgassing of the pads creating a layer of gas between the pads and rotors which can greatly affect your ability to stop from high speeds.

But one vehicle I had my 95 eclipse had ceramic pads and stock rotors.
And since the ceramic pads work at a higher temperature range.
They had great bite with minimal brake fade at high speeds.

So it all depends on what you want.
A high speed slow down
A mixed high and slow speed slow down.
Or the ability to stop on a dime even at the lowest speeds, while sacrificing some high speed capability.

[MrFishah]

For a street car, you want blank rotors without vents or drills.

Drilled is a recipe for cracking, and slotted will be a cheese grater on your pads.

Neither will provide increased stopping power in the rain, and you'll never push the car hard enough to appreciate the benefits of the slots. Drilled is not applicable anywhere outside a dedicated track car where high performance extremely thick rotors are used, and inspected/replaced regularly.

[Damkid]

slotted, drilled rotors, both or neither???

I have cross drilled and slotted rotors on my festiva... They've been on there for 6+ years (they were on the car when I bought and they're still on there) and never once caused any issues

I love them, I can get my rear tires off the ground from the braking force.... This happened when I had a B6T so no one can blame the added weight of the KL causing the rear tires to lift off the ground

[Spike]

I love them, I can get my rear tires off the ground from the braking force....

Now I want drilled and slotted just so I can put a wheelie bar ON THE FRONT. Only on a Festiva.

[Gomez]

OK given the input so far I agree on the "non need" for drilled slotted on the street car thing. But I do like the cool factor and since there is no apparent negative to having both on my car I will do it just because I can and they really aren't that expensive.

PLUS with the 05 Rio set-up I might be able to do a nice "Stoppie" too. sweeeeeeeet!!!!!

Thanks guys.

[sketchman]

I have made Aspire brakes fade once. It's not fun on a public road, and no I wasn't pushing it on purpose. But you get used to the extra time you have when you have good brakes and it happens. Anyway, I'd do the drilled rotors with stock pads. That would give you stock stopping characteristics and hopefully a bit of fade protection should you need it. My 2 cents.

[Gomez]

http://www.youtube.com/watch?v=qS5dpw6Mrc4

[MrFishah]

I cannot stress enough how strongly I recommend against drilled rotors for the street. If you insist on slotted, that's fine. Drilled are bad, and will NOT increase your stopping power.

[Damkid]

I cannot stress enough how strongly I recommend against drilled rotors for the street. If you insist on slotted, that's fine. Drilled are bad, and will NOT increase your stopping power.

I've had them on my car for years and from my experience there's no reason to say they're bad.... Have you had any bad experiences with drilled rotors??

Give me a real reason why they're such a bad product cause you're the first person I've seen who's so strongly against them

[gergorian]

These days, having a drilled rotor crack is fairly rare but can happen. If you buy a quality rotor the drill holes will be chamfered which helps relieve stresses that are found in rotors that just have just straight holes drilled. The sharp edge that is present when they aren't chamfered causes stress to build up on the sharp edge and lead to cracks. I have drilled and slotted rotors on my Probe GT and the drill holes are chamfered and I have yet to see cracks in the year that I have been DD'ing them.

I drive normally and have been intentionally hard on them at times and have noticed no fade and as I said before no cracks, as well as allowing water to escape when it rains. Choose as you wish but I would recommend them as they are better than having a solid surface as they allow for gasses to escape under hard braking which on a normal rotor can cause issues with pad bite under hard panic braking, especially from high speeds ( like on the highway.)

[MrFishah]

Of course! Just to be clear, I'm not trying to be an antagonist, and I'm not going to deny that you've had success over the years. I'm trying to relay my experience, and the experience of others, in the preaching that there are no real advantages to drilled rotors on a street car and there are potential disadvantages.

I could try to relay all of the advice I've been given by people in the industry, but I'm afraid I'd loose something in translation.

For whatever it's worth, we run our LeMons Race car with Solid (vented) rotors for up to 24 hours at a time and we have no issues whatsoever stopping in the wet or with brake fade.

Here are a few threads from another forum I'm on with people much smarter than myself:

http://www.impalassforum.com/vBulletin/showthread.php?t=322025&highlight=drilled+rotors

In a nutshell (not my writing):

The focus on thermal capacity (of the rotors--whether front OR rear) should explain itself as you read these threads, as regards the B-body, and my personal position regarding drilled and/or slotted OE rotors.

Pad choice has much to do with fade--some work at lower temps, some at higher temps. Once a rotor & pad (combined) reaches a temp above it's design limit (I can't tell you what that is), troubles like fade, "warping" (rotor thickness variation) and other deteriorative conditions begin to impact brake performance. Pad choice directly impacts what this temperature will be, and the rotor's ability to deal with the heat generated AT THAT TEMPERATURE has everything to do with how the combination performs--a rotor that can't shed heat well enough to maintain the ideal or lower temp means fade and worse. My conclusion is that for any truly aggressive operation of a B-body, where speeds may exceed 100 to 120 MPH, the car as built is borderline rotor deficient, at the least, and removal of ANY material from "new spec" (ie. drilling or slotting) lowers the thermal capacity to an unacceptable level. Throw on a set of "plus-size" (20" or larger) wheels, and it only gets worse.

"And finally, the maximum Plus Size applications for pickup trucks and sport utility vehicles (this applies to B-body, too) result in wheel and tire combinations that are significantly heavier than the vehicle's Original Equipment (O.E.) tires and wheels. This increase in weight can lead to longer stopping distances, as well as increased suspension and brake wear."

As to your last question, I can only think of a few new cars with drilled rotors "standard", and they are typically high-dollar (Mercedes, Porsche etc, and Corvette) and they are, for the most part, equipped with far more brake-to-weight compared to the stock B-body system.

Corvette drilled rotors (C6 Z51 & Z06) are both thicker and larger in diameter than the OE B-body brakes by a significant margin, and they're stopping a vehicle that weighs at least 800# less than the typical B-body. I have far less issue with using such rotors than drilled OE-size B-body rotors....but still don't or won't recommend them.

The typical service approach with the top-line European or other cars with drilled or slotted rotors is a matter of replacing them at each brake service interval, not turning them or just replacing pads. The factory/franchised dealers for these cars take a much different approach to the performance of this vital safety system maintenance than the average Chevy owner who does much of their own work in order to avoid paying a dealer or shop they don't--for whatever reason--trust, or as a matter of finances. The guy that can afford a Mercedes or Porsche just pays the bill at the dealer and knows he's got "as-new" brake performance until the next time that maintenance is needed.

FWIW, the new (C7) Corvette has done away with drilled rotors, I'm pretty sure. Have not confirmed, and have not tried to find out why....but there WERE some issues with the C6 drilled rotors reported from time to time over the 8+ years they were used.

For anyone saying "but they're used on racecars"....the budget and system maintenance approach for a normal between-events service of a pro-level race team will include complete service and/or replacement of the brake components, especially anything that is a wear component, like rotors.

That is not how any typical B-body owner approaches the same system maintenance for daily street use. Drilled rotors on racecars are used once and taken out of service--whether offered up as used parts for sale, or to be used as door stops or jackstand bases.

[zoom zoom]

I have slotted rotors on babyspire and I love them. Roughly 10k maybe a hair less on them. They take a minute to get warmed up but after you slow down twice from 35mph they're good to go. Stock pads and I have noticed a bit of brake dust on my rims so thats something to consider.

I am looking for another source for slotted rotors, if you find em hook me up with a link please! (Aspire rotors)

[sketchman]

Fishah, what kind of pads do you use on the race car?

I have solid rotors right now and stock cheapo OE pads. I have made them fade AND warped the rotors. They are warped right now as I decide what to do before I pull the parts to change to Blue. I like the stopping character of stock pads. I don't want to think about the pads reacting 2 different ways on the street in traffic, etc.

Giving the overheated pads a place to send their vaporizing selves should help shouldn't it?

[MrFishah]

We use a racing compound. Carbotech XP8.

It's not a compound that I'd recommend for the street, but we have used aggressive street pads before without fading issues. For full disclosure, we have 11.5" MiniCooper Rotors with Dual Piston Subaru Calipers, so we aren't exactly talking about stock Festiva brakes.

My opinion still stands though, that high quality solid rotors with the right pads are the best for a street car and even a car that sees the occasional track day.

More important than slotting/drilling rotors, is to inspect all your brake lines (hard and soft), flush and bleed fluid to make sure it's pure, and potentially switch to a higher quality brake fluid. All of these things will go farther towards improving your braking ability than slotting/drilling rotors will.

----

Also, have you considered running ducting to your brakes? Aimed directly at the Calipers? That may help if heat is your main issue.

Also x2, when you say you're running solid rotors, I assume you mean they're still vented right? If you have solid rotors without venting, I've found your problem