They only make them one way... doesn't matter, the slots cut the pads, keeping everything flat, no grooving, no problems

There are no rights and lefts

 

they did....

though the new Challangers all come that way as well, so the slotted rotors from Chrysler must not be directional..

pretty stupid if you ask me..

read this: http://www.zeckhausen.com/how_to_properly_install_rotors.htm

 

Those rotors are directional because of the internal cooling fins. Not because of the external slots IMO. The external slots could be straight, slop forward or rearward and it wouldn't make a bit of difference. The slots are there to cut the pads and keep them flat.

I haven't looked but perhaps the DCX ones have straight internal fins so direction isn't important.

When a centrifugal fan is designed it can have blades on the impeller curved forward, (low pressure), or backwards, (high pressure), or straight, (normally used for industrial exhaust that has alot of debri in it). No matter though, they all blow air the same way, from the center of the impeller outwards, regardless of the blade direction.

Don

they did....

though the new Challangers all come that way as well, so the slotted rotors from Chrysler must not be directional..

pretty stupid if you ask me..

read this: http://www.zeckhausen.com/how_to_properly_install_rotors.htm

 

there you have it.

 

The slots are there to cut the pads and keep them flat.

I always thought the primary function of slots was to scavenge hot gasses from the pad/rotor interface to increase friction and facilitate heat generation (conversion of kinetic energy to thermal energy) and heat dissipation (venting).

Educate me.

 

true

they will serve that function at high speeds and heavy usage, Lou. Gas released from the pad acts like lube and a slot is a means of escape, giving marginally better performance.

Slots also "cut" the pad at lower speeds and act to expose new pad and remove glazing, etc.

It is important to note that the pad is more important than the rotor design in affecting brake performance. And the Mopar rotors are "any directional", it makes no difference which way they rotate.

 

Recently installed "Power Slot" front rotors. Each rotor is different in the direction they vent, so they both vent to the rear as viewed from the top. First clue was the big "L" & "R" on their respective boxes!!

Cheers CANDYAPPLE:beerchug:

 

Yep, they can be either way and it makes no difference to the gases or the pads. Aftermarket and high end folks go to the extra effort to make them directional because folks expect it. But it doesnt make any difference.

 

Matt talked a fair bit about this in his "Reloaded - Brakes" thread - but that picture Mr. I posted explains it well. And like he said - if the rotors' internal vanes are non-directional, it doesn't really matter too much; but if they are directional, then it makes a lot of difference (the direction of the vanes, not the slots).

As far as I know, all our factory rotors are non-directional.

 

If you look at the inside surface of the rotors you will find that the slots are oppsed to that on the outside surface, making them omni-directional. Just my .02.

All SRT8 rotors are universal (frts) L&R,

I beleive the rear L&R are different, as the Left (I think) has the interior parking drum brake assm. and the right does not. Check me on that though, its been awhile since I messed with my rear rotors. (Just look in the parts manual)

 

GGR's got it exactly right. Its the fins that are of concern, not the slots. The SRT rotors are omni directional because of their fin design. One part number covers both L&R front rotors.

 

well, I would like to quickly address something; not to be argumentative, but more to try to clarify. When it's said that the slotted rotors "cut" into the pads, I believe that to be a miss. I completely understand the slots vent gases, and even wear away imperfections that build up on the pad - but to say that it cuts away more material than a non-slotted rotor, I believe, is untrue. When you think about it, the slots are made into an existing flat rotor, hence making the slots not any more abrasive than non-slotted. The slots add an ability to flatten the pads, but not to cut them. Am I mistaken? Hmm... GOOD DAY!

 

well, I would like to quickly address something; not to be argumentative, but more to try to clarify. When it's said that the slotted rotors "cut" into the pads, I believe that to be a miss. I completely understand the slots vent gases, and even wear away imperfections that build up on the pad - but to say that it cuts away more material than a non-slotted rotor, I believe, is untrue. When you think about it, the slots are made into an existing flat rotor, hence making the slots not any more abrasive than non-slotted. The slots add an ability to flatten the pads, but not to cut them. Am I mistaken? Hmm... GOOD DAY!

My trunk monkey had a litter of baby trunk monkeys so I directed her to have them hang out at the four corners visually inspecting things during hard braking.

They have reported back that the slots vent gasses and help keep schmutz off the pads, but they observed no "cutting" of pad material.

But then, who are you going to trust? A bunch of trunk monkeys or the experts on this forum?

Beats me!

They may have just been monkeying around.....

 

hmm...you make a good point, Lou.

 

^^^^Well, dang! I guess I'm going to have to spank my trunk monkey babies for monkeying around and false reporting.

But....you guys aren't going to accuse me of spanking my monkey, are you?

 

^^^^On a more serious note. I recently installed a set of OEM SRT8 slotted rotors and pads but had them cryogenically treated first. Early indictions are positive.

A few young persons begged me to "take them for a ride" the other evening and I did--at great speed and requiring near max effort braking repeatedly for a 10-15 minute period with a heavy load on board.

When I got home, many new and unusual aromas were emanating from the four corners and I wondered if I had over-cooked or warped the rotors.

Next day, brakes performed flawlessly.

One session of hard braking is not a very comprehensive test, but there was no fade during the session and no warping or visible signs of excess wear the next day.

I'm going to run them at Sebring for several sessions over two days in early September, so I will have a comprehensive report by then, but so far so good.

The shop that does the cryo work tells me that all of the Clearwater area police departments, taxi companies and school districts have their rotors and pads done at his shop. The claim is that it extends the life of the rotors and pads by a factor of 3-5X.

Lou

 

Hah. You just need to find monkeys that drive. If you want I can take pictures. I'm going to the track Friday. Its a fine powder that clogs the slot.

Thats why some of the guys who slot rotors brag about how their slots terminate and help exhaust the stuff.

 

Matt, thanks for the information. Indeed, the massive amount of compression that the pads receive would, in fact, push material, no matter how slight, into the grooves causing cutting. That does make sense entirely. Foolish me.

 

Lou I hope you have better luck with your cryo treatment than I did. My suspicion is you will as I was beating mine hard ... wait that didn't come out quite right. I mean... I was spanking them really ... no wait.... um. Never mind.

My cryo'd rotors lasted a grand total of one day at Laguna Seca. I had the powered ducts then but they still cracked. Now... they did crack less than the last set of rotors I cracked in one day. Quite a bit less. They were still usable and I still have them in the garage. So if that very unsicentific result means anything I'd guesstimate a 2x-3x improvement. I temp-tested those rotors with temp-sensing paint the day I cracked them and the outer edges were going over 1200 degrees in the front at the outer edges and nearly that near the hat. I'm not sure anything can save a rotor that gets that hot.

For me, the solution was to just buy cheaper rotors and treat them as a disposable item. My cryo treatment alone ran about $65 and two new SRT rotors were about $125. They crack a little too, but not as much and at that price I don't care.

 

thanks

Lou I hope you have better luck with your cryo treatment than I did. For me, the solution was to just buy cheaper rotors and treat them as a disposable item. My cryo treatment alone ran about $65 and two new SRT rotors were about $125. They crack a little too, but not as much and at that price I don't care.

Thanks for the real world testing. I have always wondered at the whole Cryo thing.

It is amazing that SRT8 rotors can be had so cheaply.

Lou, make sure you bed the rotors before tossing them out as "warped". The whole bedding thing has completely destroyed my perception of "warped" rotors. We now re-bed at the first sign of pulsation or wobble under braking and it has fixed EVERY ONE!

 

^^^ I was going to say.. Didn't Matt try cryoing rotors...