Are the rotors sold at local/chain shops (e.g., Autovalue) fine for running laps?

[shadezofgrey]

Hey everyone,

My situation is that I want to pick up a set of rotors (and a matching set of brake pads) that I can slap on the car for lapping events at Race City, etc. I've called around to a few of the local chain stores (e.g., Autovalue, Partsource, etc) and have found that the rotors they sell tend to be sold at a cheaper price than what you could find online (not to mention being readily available and blank as opposed to being slotted/drilled/both). Thing is though that I'm not really familiar with the different brands they carry (or any brand really) nor do I know much about the design/materials used in making them. Likewise I'm wondering to what extent is the difference in price because you're paying for the name as opposed to a difference in quality. In short then I'm wondering what are peoples opinions on the el cheapo rotors you can buy locally and in turn whether they'd be fine for running laps.

FYI I've never gone lapping at the track before, so I just want to make sure that I'm not cutting costs on something that could end up making the difference between having adequate braking power during your time on the track vs goin out in a fiery death roll of glory (k well I guess that'd be kinda cool).

Thanks!

[e31]

It helps to know how much your car weighs (in otherwords: What do you drive?)

Keep in mind that in most cases the OEM brakes are good for shit after you build up some heat, so spending the extra chump change for drilled/slotted rotors to vent excess is always advised.

[tsi_neal]

track pads and cheap rotors is all you should need.

by track pads I mean real track pads not a performance street pad. I say cheap rotors because most track pads eat rotors.

Almost forgot high temp brake fluid is probably more important than the pads or rotors. a fresh and complete bleed of at worst the ford dot 3 (rated for ~500 *f)

[Aaron@Tuner]

Yep for the most part, just go for a solid rotor and get some nice track pads. If you're looking for something not too expensive, come see us for some Hawk race pads.

If you do want some "fancy" rotors, don't go for drilled as they do tend to crack with track use. Most cross-drilled rotors come with a warning that they are not to be used at the track.

Don't forget the brake fluid too! Just take her easy at the track and mix in some cooldown laps for your brakes.

[Zero102]

As said above, cheap rotors are fine so long as they are not drilled or slotted. Track pads are a must, they will be the limiting factor most likely, but also make sure you have VERY RECENTLY changed your brake fluid (when tracking a car, 6 months is considered old-age for brake fluid).

[Pollywog]

Pm me your vehicle and I'll pm you prices on rotors, their quality and availability.

[rusich]

Not to hijack the thread, but I got by rotors warped after 60,000 K of regular driving on my Hyundai Entourage. (heavy van) And I am just thinking weather the OEM brakes had defect or not.

1. Would you machine the rotors?
2. Replace rotors and pads with OEM?
3. Upgrade to aftermarket?

[Tomaz]

Nice hijack...

60k, i would do a replacement. Anytime I replace, I upgrade from factory.


So, if track guys are recommending solid rotors and race pads, what the point of slotted and drilled rotors?

[Graham_A_M]

^ looks. :facepalm: Thats it....

[g-m]

slots prevent glazing iirc by ensuring that there is always fresh pad material. Holes are pretty much for looks unless you're still using an organic pad that will outgas

[Scuderia]

^Like someone said, mostly for looks. The holes and slots obviously dissipate heat better than a solid rotor, but have a big weakness when used at the track, because the extreme heat makes the thinner parts so vulnerable to cracking.

[g-m]

thats false, they don't dissipate heat better, the solid rotors do. The vaning on the inside of the rotors are the main heat dissipation mechanism. Most rotors have straight vanes with high end rotors having directional vanes. If you buy rotors with directional vanes you must mount them correctly. Solid rotors dissipate heat better because they don't crack around the holes and they have a larger thermal mass to absorb heat.

[Scuderia]

Originally posted by g-m
thats false, they don't dissipate heat better, the solid rotors do. The vaning on the inside of the rotors are the main heat dissipation mechanism. Most rotors have straight vanes with high end rotors having directional vanes. If you buy rotors with directional vanes you must mount them correctly. Solid rotors dissipate heat better because they don't crack around the holes and they have a larger thermal mass to absorb heat.

No, that's false, the solid rotors don't. Yes, the vaning on the inside is the main mechanism, but both crossdrilled/slotted and solid rotors have the vanes, directional or not. A larger, flatter surface area creates ideal conditions for glazing and heat fade and build up of brake dust. The vents on performance rotors transfer heat and dust to themselves, leaving the solid area on the rotor to do it's job. It's all overhyped and crossdrilled/slotted rotors are not worth it, but technically speaking, they do dissipate heat a bit better.

[Zero102]

http://www.girodisc.com/newspict/cracks.jpg

[Twin_Cam_Turbo]

I heard its better to have a rotor cast with the slots/holes than having them machined in afterwards, can anyone confirm?

[jdmgt]

depending on your car and your skill level. buying a "race" brake pad may be useless.

running a race brake pad and not getting them up to operating temp is a waste.

i run oem nsx pads and brembo slotted rotors on my civic. tracked the car for the last two years and have never got any brake fade or warped rotors.

proper brake pad bedding is the key to having good brakes.

Hawk HPS is a good street brake pad

[962 kid]

Originally posted by Zero102
http://www.girodisc.com/newspict/cracks.jpg

http://lh5.ggpht.com/gnatster/SItr-Mc1q5I/AAAAAAAAC2c/8ddLYm4h7Sg/s800/cracked%20Wilwoods.jpg

http://i68.photobucket.com/albums/i15/rbeziat/Daytona%20HPDE%20Dec%2008/DSCF1330.jpg

:rolleyes: I forgot, drilled rotors are the only brake discs than can crack


Originally posted by Twin_Cam_Turbo
I heard its better to have a rotor cast with the slots/holes than having them machined in afterwards, can anyone confirm?

Definitely true. Most of the bad rep that drilled rotors get comes from companies that drill the holes, rather than cast them in place.

[shadezofgrey]

wow, thanks for all the replies so far guys, the responses have been really helpful!

I guess the coles notes of what's been mentioned so far include:

-vanes = the more crucial design element
-slots can help in terms of some added cooling, getting rid of debris, and fighting glazing of pads
-unless I'm rockin ancient ass brake pads that give off gas I think holes aren't gonna be much use for me
-the variation in rotor design/performance *may* not be as noticeable as the variation you'd see in using decent vs. subpar brake fluid/pads
-casted + slots/holes > slots/holes that are tacked on as an afterthought

Other than that, I think my absolute lack of experience on the track means I prolly won't be exploring the limits of grip or late braking my first few times... so given that and everything else I'm guessing I should be good with the el cheapo rotors (Auto Value here I come!).

I also just wanna thank Aaron at Tunerworks, spoke with him earlier and his track experiences/general knowledge helped me get a better sense of what I'll need for braking power.

oh yeah, one last thing, read this article while I was looking up info on rotors:

http://www.g20.net/forum/showthread.php?t=91131

thought it was kinda cool as it talks about Porsche's design philosophy re: rotors and how they incorporate the use of slots/holes... with that being said though ultimately I wonder how useful they are - to put it into perspective do F1 cars, etc incorporate any of this stuff into their rotor designs?

[shadezofgrey]

Originally posted by e31
It helps to know how much your car weighs (in otherwords: What do you drive?)

Keep in mind that in most cases the OEM brakes are good for shit after you build up some heat, so spending the extra chump change for drilled/slotted rotors to vent excess is always advised.

oops just noticed this post - um, car weighs around 3000 lbs or so with driver - how does that added info help (teach me!!!)? and it's just another faceless Honda in Calgary lol (i.e., an rsx)

[Zero102]

Originally posted by shadezofgrey
Other than that, I think my absolute lack of experience on the track means I prolly won't be exploring the limits of grip or late braking my first few times...

While you may not be pushing your braking to the last possible second, or entering every corner at the top speed possible, you WILL be testing your brakes to their absolute limits because you are so new at this.

A lack of experience almost always leads to hotter brakes, once you learn the correct braking zones, entry speeds and so forth you will find yourself using your brakes a lot less than when you first start.

I am not saying you need to go with some crazy braking setup, I just want to correct the myth that you can get away with less when it comes to your brakes simply because you are new. You are fine on stock brakes, just make sure they are in perfect shape for your own safety.

[Zero102]

Originally posted by 962 kid
:rolleyes: I forgot, drilled rotors are the only brake discs than can crack

Or maybe I posted that picture because it showed the mode of failure typically experienced by a low-end aftermarket drilled rotor, with the holes way too big and too close together. Something that many people on here may be tempted to buy. (I am not saying the picture IS of one, just that the appearance of the bad ones is similar, and unfortunately, so is the mode of failure)


Of course any brake rotors can crack or fail, I don't recall saying that the other types of rotors were invincible. My point was simply that crossdrilled rotors have the highest rate of failure, usually due to mis-application and/or flawed design, and that they are by far the most popular for all the wrong reasons, so occasionally it is worth being reminded that adding crossdrilled rotors to your car does not equal better or safer brakes, ESPECIALLY for new racers.

[tsi_neal]

As its your first time to the track and your just trying it out, bleed your brakes with a reasonably high temp DOT3 or 4 and have fun. When you start to smell your brakes take a cool down lap and park the car. When you park the car DON'T apply the park brake or hold you foot on the pedal. Once the brakes are cool go out again.

I won't regularly take any car to the track without the right brakes but if its only once or twice you can still have fun, it will just be 3-4 laps at a time...

[sillysod]

All i have to say is don't buy the super cheap chineese brake rotors from cdn tire unless you really enjoy steering wheel shudder everytime you touch the brakes after your track day.

[shadezofgrey]

Originally posted by Zero102


While you may not be pushing your braking to the last possible second, or entering every corner at the top speed possible, you WILL be testing your brakes to their absolute limits because you are so new at this.

A lack of experience almost always leads to hotter brakes, once you learn the correct braking zones, entry speeds and so forth you will find yourself using your brakes a lot less than when you first start.

I am not saying you need to go with some crazy braking setup, I just want to correct the myth that you can get away with less when it comes to your brakes simply because you are new. You are fine on stock brakes, just make sure they are in perfect shape for your own safety.

ohhhhh yeah. lol, good point, thanks for the heads up, didn't think of it that way

[shadezofgrey]

Originally posted by tsi_neal
As its your first time to the track and your just trying it out, bleed your brakes with a reasonably high temp DOT3 or 4 and have fun. When you start to smell your brakes take a cool down lap and park the car. When you park the car DON'T apply the park brake or hold you foot on the pedal. Once the brakes are cool go out again.

I won't regularly take any car to the track without the right brakes but if its only once or twice you can still have fun, it will just be 3-4 laps at a time...

yep, I plan to drain the brake fluid + throw on new rotors + pads right beforehand.

btw, what would happen if I did leave the brakes/hand brake on? would stuff that shouldn't end up sticking together due to the heat? at any rate thanks for the heads up on that + what to do once I smell burnt brakes.. really glad to be learning this ahead of time lol

[shadezofgrey]

just thought I'd throw out somethin else that I was thinkin about...

how exactly do people go about breaking in brand new set of track pads/rotors? do a few warm up laps on the track (assuming it's permitted) to get the pads worn in? buy pre-worn (or whatever it's called) pads? repeatedly drive up to/slow down from excessively illegal speeds on public roads? what exactly? I'm pretty much good with anything but option c - I don't really feel like doing anything dumb

thanks

[tsi_neal]

Originally posted by shadezofgrey


btw, what would happen if I did leave the brakes/hand brake on? would stuff that shouldn't end up sticking together due to the heat? at any rate thanks for the heads up on that + what to do once I smell burnt brakes.. really glad to be learning this ahead of time lol

Yea thats pretty much it, at worst the pads will perminantly glue themselves to the rotor. more likely they will leave deposits making the brakes pulse.



Originally posted by shadezofgrey
just thought I'd throw out somethin else that I was thinkin about...

how exactly do people go about breaking in brand new set of track pads/rotors? do a few warm up laps on the track (assuming it's permitted) to get the pads worn in? buy pre-worn (or whatever it's called) pads? repeatedly drive up to/slow down from excessively illegal speeds on public roads? what exactly? I'm pretty much good with anything but option c - I don't really feel like doing anything dumb

thanks


Different manufactures have different requirements, but basically its 10-20 stops in increasing speed and brake effort untill you get brake fade, then park the car till the brakes are cool. The idea is you want to SLOWLY put heat in the pads and get a nice layer of pad transfer without glazing, doing a couple quick hard stops will get the heat in but without the layer of pad transfer is more likley to glaze the pads. Its probably best to do it in the first session of the day, tell the other guys on track that you will be so they can give you space.

[YamahaV8]

For a aftermarket rotor available from a parts store I have tried and like ATE rotors. I have never tracked with them but I was happy with there performance on my overweight, under-braked car I had. I also had ceramic pads which probably helped a lot too though. I don't know if the grooves those rotors have will have the same tendency to crack as slotted rotors under heavy use.

[Zero102]

To bed in new brake pads you should find a road with a speed limit of at least 80km/hr that is not busy.
Accelerate to 80-100km/hr, then while holding the accelerator ride the brakes for 5-10 seconds to heat them up, then brake down to 10, then repeat for at least 4-5 stops. If you do this quickly enough on the last 1-2 stops you should start getting brake fade. From 80 km/hr this may not happen unless you really step on the brakes and stomp on the accelerator to get back up to speed, but if you can go 100km/hr or higher it is pretty easy to do.

Once this has happened, proceed at speeds not below 20-30km/hr until the brakes have had a chance to fully cool (minimum 3-5km). If you must stop then stop early and roll slowly ahead or you risk making an uneven layer of pad material on the rotor and you will have pulsing brakes.