Crossed drilled/slotted rotors

[SPYDER_MAN99]

Hey I was thinking about putting crossed drilled/slotted rotors on my car. One of my friends put them on his 3rd gen eclipse and when he brakes they smoke a lot! I was wondering if that was just the rotors that he bought or if thats what all of them do?

Thanks You!

 

[flinguist]

I've got 'em on my car, and they don't do that. The smoking is probably caused by the type of brake pads your friend is using. Most people that know anything about brakes don't recommend drilled rotors, because there may be an increased risk of the rotors cracking under heavy use.

 

[SPYDER_MAN99]

So your saying that you should just get them slotted? and also do you think ceramic brake pads would hold up to the rotors? Thanks for the reply

 

[steve]

Slotting is the better choice for people that care about things other than looks.

Steve

 

[speedy13]

Slotting is the better choice for people that care about things other than looks.

Steve

Amen.ceramic brake pads or good,but they wear out faster then semimetallic.I would go with something harder then ceramic,specially on slotted rotors that accelerate the wear on brake pads.bottom line is,sue drilled rotors do look cool,i can't argue with that,but they are just for track cars that don't care about just throwing out rotors and brake pads since they probably get taken apart every other race or so for inspection and all they care about is faster lap times,not street durability.ya feeeel me?thats my 10 cents,my 2cents is free...

 

[ragedylaser41]

from what i've heard you might need the paycheck of micheal shumacher to pay for pads - that and why do something like this - less for the pad to grab ahold of - and you won't be on your brakes hard enough (unless you lock them up) to get them THAT hot - thats what the vents in the front of the rotors are for now - to me - on import and dsm car - it'd be a waste of money - but remember, thats just my opinion.

 

[Talesin]

The only real times you'll need anything beyond the standard rotors is if you're doing track days often, or if you switch between heavy accelleration and rapid decel often... not meaning driving in Los Angeles traffic, more the wear pattern of enjoying a downhill mountain road at exactly the speed limit. With the standard rotors, I get heavy brake stink after a good downhill run. It's hard to miss if you have a nose, and that's the only time I can see needing slotted/vented rotors... you'll be replacing them shortly if the assembly is getting that hot anyway, as the rotors start to warp.

Be very careful if you go for cross-drilled though. One of the other (non-DSM, a Honda kid) guys who enjoys the same roads I do had 'em, and had his passenger-front shatter. Managed to safely stop with the emergency brake, but it scared the living crap out of both of us as I was driving behind him at the time. He ended up needing a new caliper assembly; the rotor managed to dent the piston after the pad tore off, apparently.

 

[FullyBuiltDSM]

i was watching aomthing on the speed channel and it explained that drilled rotors actually get rid of so much of the rotor that it makes them hot really fast. they said slotted is the way to go.

 

[EclpzLvr97]

"Green stuff" pads good with slotted rotors then huh?

 

[injector]

i got the EBC green stuff because i get them 50% off where i work at and all i can say is that my car stops on a dime now, i got new rotors too but they are just regular not slotted or drilled, there is one problem to the green stuff pads tho, they are designed to be used with drilled rotors wich means the compound on the pad is HARD and it's going to eat away your rotor if you don't have drilled rotors you'll end up replacing the rotors before the pads. if you'r not going to the track and if you just want really good braking get the just EBC's green stuff they work great even with regular rotors, just remember to let the pads and rotors sink in for about 200mi before you do any kind of really hard breaking or you can get crystalising and warp your brand new rotors

 

[EclpzLvr97]

i got the EBC green stuff because i get them 50% off where i work at and all i can say is that my car stops on a dime now, i got new rotors too but they are just regular not slotted or drilled, there is one problem to the green stuff pads tho, they are designed to be used with drilled rotors wich means the compound on the pad is HARD and it's going to eat away your rotor if you don't have drilled rotors you'll end up replacing the rotors before the pads. if you'r not going to the track and if you just want really good braking get the just EBC's green stuff they work great even with regular rotors, just remember to let the pads and rotors sink in for about 200mi before you do any kind of really hard breaking or you can get crystalising and warp your brand new rotors

So uh, I'm confused. EBC green stuff is or is not good for regular rotors?

 

[wret]

it's going to eat away your rotor if you don't have drilled rotors you'll end up replacing the rotors before the pads.

I've heard just the opposite. Due to their high kevlar content they are reported to be easier on rotors than other compounds. Are you saying this from experience or can you site a source of this information?

 

[hereitcomes]

having drilled/slotted rotors are better for stopping power. the holes on the rotors help the brakes disperse heat evenly and faster. I used a semi-metalic on my Brembo Drilled rotors and they stoped exellent every time.
Ceramics are too hard for the metal that is used on aftermarket rotors. The pads cant grab the rotors so the either smoke, squeak, or destroy the rotor and you will have to machine it, or replace it.
Ive had great luck/experience with them and they are exellent for stopping quickly in heavy traffic. good luck guys.

 

[injector]

I've heard just the opposite. Due to their high kevlar content they are reported to be easier on rotors than other compounds. Are you saying this from experience or can you site a source of this information?

not from my expirience but from by boss, he has a toyota seqoya, a CLK 230, and a RX-7 all with EBC green stuff and drilled/slotted rotors he told me that the pads ate up the regular rotors.

So uh, I'm confused. EBC green stuff is or is not good for regular rotors?

they're good but not practical if you're on a tight budget

Ceramics are too hard for the metal that is used on aftermarket rotors. The pads cant grab the rotors so the either smoke, squeak, or destroy the rotor and you will have to machine it, or replace it.

that never happened to me or my boss even when he has all his 3 cras with regular rotors

 

[wret]

I don't have any evidence to the contrary but we should be careful not to spread statements based on such a small bit of anecdotal evidence. We cannot verify that the sequoia brake rotors wore faster with any particular pad or rotor, and even if we could we still would not have enough data to say that one of the most popular brake pads, being of a softer material, actually causes greater rotor wear.

On the subject of drilled rotors, most experts agree that they are a gimmick. The only improvement is appearance and safety is compromised. Others will argue the benefits of them all day long. I do know this: go to a Porsche club race and you will find a hard time finding a rotor that is not drilled. Yeah, yeah, they use a special process and the holes are molded into the rotor. I have used both and can detect no difference and I will probably never be driving fast enough on them to have to worry about catastrophic failure.

 

[FORMONTOYA]

my personal experience...i had ebc greenstuff and braided lines on my factory rotors. great combo, improved stopping power. the problem was not pads eating rotors but the pad being able to tolerate much more heat than the tiny 10" rotors could handle repeatedly. after 2 sets of greens the front rotors were noticably stress cracked and then i replaced the rotors with the power slot plus. the bigger rotor has no problem hanging with the greens now. the greens are good with slotted rotors, they just wear down a little quicker than with oem rotors.


jim

 

[BGGSTin]

All pro road track cars I've ever seen have only slotted rotors. LIke the Le Mans Corvette and such all run with slots only, now I'm sure they're using higher grade materials that are way out of our budget but I'm sure the same principles for slotting - only applies. I can't say why because I havn't researched it enough yet, all I know is that if it's run by pro road coarse racers, It's definitely going to be able to withstand any abuse thrown at them on the street.

 

[flinguist]

All pro road track cars I've ever seen have only slotted rotors. LIke the Le Mans Corvette and such all run with slots only, now I'm sure they're using higher grade materials that are way out of our budget but I'm sure the same principles for slotting - only applies. I can't say why because I havn't researched it enough yet, all I know is that if it's run by pro road coarse racers, It's definitely going to be able to withstand any abuse thrown at them on the street.

Not true. I was watching one of those speed channel shows, and they were upgrading the brakes on a 'Vette `(I think) for road track use with drilled rotors. The rotors were not drilled completely through though. This brake system they were installing was supposedly top of the line, and the preferred one for road track use.

 

[Fabian972]

Well if you want a good bite when you break slotted it the way to go ...you may even try slotted/dimpled combination to keep down the temp in your rotors and maintain the integrity of the rotor. Good luck

 

[Carter97GSX]

I'm running the willwood 4 piston caliper kit, it came with cross drilled and slotted rotors and it works terrific. I've jammed on the brakes at 140+ mph more times than I'd like to admit (in a highly safe area mind you) and I have had no problems. The way I see it, if I'm paying three grand for a brake kit and it comes with cross drilled and slotted rotors then those are probably the way to go. Otherwise the better brake kits would not come drilled right?

 

[BGGSTin]

Not true. I was watching one of those speed channel shows, and they were upgrading the brakes on a 'Vette `(I think) for road track use with drilled rotors. The rotors were not drilled completely through though. This brake system they were installing was supposedly top of the line, and the preferred one for road track use.

Umm...how can you say, "not true," Speed channel, well the "Speed Channel" doesn't have the credibility to me as a professional corvette Le Mans team. If I had a scanner I'd upload pictures of it that my dad took of it at MIS last year.
I don't care if you challenge the premise of drilled vs. slotted rotors...but don't challenge me by saying one of my statements was "not true."

 

[Mist3r Spool]

I have the typical Baer setup with cross-drilled and slotted rotors. I've never had any smoke when nailing the brakes. I've had them installed for about 2 1/4 years with a lot of hard braking and everything is working really well.

 

[ddavisaf]

Here is the simple truth.

Slotted- disperse the layers of gas that forms during braking allowing the pads to keep better contact with the rotor. The gas is what heats to rotor due to the combustion of the pad against the rotor. Since the gas is allowed to escape, less combusion, cooler rotors.
Drilled- Same principal, it allows the gas to escape from inbetween the pad and rotor.
Drilled and Slotted- These rotors use both techniques, however due to the amount of material removed from the rotor, they are more prone to warpping and cracking.
Which is better? Since Slotted rotors have the most material out of all three kinds the Slotted rotor will last the longest. Next the Drilled, the Drilled and Slotted.
Boom, that's it.
After this you're getting into brake system that are hybrid systems of the two, dimpled, half or quarter drilled. etc etc... Don't even worry about this....

Here is a post from the vfaq.

It is possible to buy these types of rotors. Opinions on them vary, but it is unlikely that the average owner (or weekend racer) is likely to see much improvement.

The idea behind all of these altered rotors is to keep gas from becoming trapped between the pad and the rotor. The vents, slots or drills are intended to give the gas an escape route. Also, they are thought to improve rotor cooling. Both of these factors are intended to combat brake fade, where the brakes stop performing well when hot.

Unfortunately, they can all weaken the rotor and make it more susceptible to warping and cracking. Complaints of cracking are especially common on from owners of cross-drilled rotors. And most people have problems with overall brake performance rather than brake fade.

In most cases owners would be better off upgrading to Big Brakes or performance brake pads. These will certainly provide better overall braking performance.

 

[Supercow]

I've got slotted and drilled rotor's from rotorpro's and am using ebc greenstuff's up front and hawk pads in the rear.

after a year i'm still pleased. I know that the rotor's probably didn't actually improve my braking much but no matter how hard a push it on country roads i never get any brake fade where the stock stuff had a good bit. I had to replace by stock rotors anyways so the upgrade was a no brainer.

 

[Piranha451]

I read somewhere that the reason cross drilled is not recommended for street performance rotors is due to the parallel (straight) cooling vanes whereas the racing/performance rotors have curved cooling vanes, hence the diagonal pattern of the cross drilling. With the street rotors the paralled vanes along with the diagonal pattern will take material away from the vanes as the hole is drilled through the divider, thus weakening the rotor. EBC has slotted/dimpled rotors that look quite interesting with this description on their website:

The wider slot actually draws cool air across the pad surface keeping pads and rotors cooler. They also expel dust, dirt and hot gases better than fine slots which eventually fill with rust and scale and become ineffective in our opinion.
The blind drilled holes break down surface gases when braking from speed but do not weaken the rotor cross section as can happen with through drilling, thereby lessening the chance of rotors cracking over time and heavy use.

Has anyone tried these? If so, what are your thoughts about them as I am considering them myself.