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Most "normal" cars come with straight vane rotors, with internal cooling vanes that extend straight from the center of the rotor outward, like spokes on a wagon wheel. (See drawing on lower right) These rotors are not as efficient at cooling, but they are less expensive to manufacture and car dealers only have to stock a single part for both sides of the car.
Some higher performance cars come with "directional rotors", which have curved or tilted internal cooling vanes. These curved vanes pump more air through the rotors, resulting in improved cooling efficiency. Thus, there is a left and a right rotor. When the directional rotors are properly installed, these internal vanes should lean toward the back of the car - as shown in the diagram on the lower left.
Slotted rotors
As with the plain rotors discussed above, the internal vanes should lean toward the back of the car. The direction of the slots on the outside of the rotor do not dictate whether the rotor is a left or a right. For rotors with slots machined in the same direction as the internal cooling vanes, the slots should lean toward the back of the car. For rotors with slots machined in the opposite direction as the internal cooling vanes, the slots should lean toward the front of the car. Bottom line - don't use the slots to decide which side to mount the rotor. Pay attention to the internal cooling vanes.
For slotted rotors with straight internal cooling vanes, the direction of the slots is totally up to you and what you think looks best. In this case, there is no wrong answer.
Drilled rotors
It is not possible to tell if a drilled rotor is installed properly, simply by observing the drill pattern. Different manufacturers use different patterns with spiral "arms" that appear to lean in either direction, regardless of the internal cooling fin orientation. For example, StopTech AeroRotors, used on their big brake kits, have a drill pattern that appears to lean to the front of the car. Porsche OEM rotors have a drill pattern that appears to lean to the back of the car. In both cases, the internal cooling fins are properly oriented, leaning backwards. But the drill pattern is opposite. This is why Porsche mechanics often install StopTech big brake kit rotors backwards, despite the big "L" and "R" stickers on the rotors! They're relying on the drill pattern, rather than the direction of the internal cooling vanes.
As with slotted rotors, one must check the direction of the internal cooling vanes in order to determine the proper orientation of drilled rotors.
After looking at the install kit, it looks like the fogs have to go to use it. I spent a bunch getting the fogs & like them so I think I'll be offering the brake ducts for sale.
Nah, just when I was living in the desert, rust on the rotors wasn't really A Thing(tm).
Moved to the swamp, and they'll look like that any given morning.
There's been a couple amusing threads here on Azine, that I recall, about people throwing hissy fits about rust on the rotors of their new fancy luxery acra car. Hence it's only an issue on the internet.
Yours looks good to go to me. I wouldn't give it a second thought.
I would hit them with a wire wheel on a drill though...and paint the hub hats with black caliper paint for looks.
I redid my S2k ones recently since the wheels look so perfect now.
I had a clunk, an end link loosened so while I had the wheel off I tried to use the disks, the hats are in the way for the OEM calipers so no slotted rotors until I'm ready to r&r the calipers.
I'm not sure I understand...
You mean the caliper was in the way of prepping to paint it?
I removed from the car...I also didn't tape up the caliper face...let the
pads burn the overspray off after.
I have never seen her so sad/mad/crazy. She was cursing herself for not going sooner and to make matters worse, I could not enjoy the rare as hen's teeth admission I was right. (I told her to go last week)
I'm not happy with whoever told her (I don't know yet) there was no reason to not let her travel without knowing, she was already going today.
gravity will take the air up, right? do you need to bleed those off the car to get it properly?
If each piston has it's own hydraulic chamber how would the air go DOWN?
It looks like your bleeder is a vacuum bleeder, right? It connects to the valves on the calipers and pulls fluid through and out?
If so, physics would suggest that you start from lowest to highest point since, like DeerMeat noted, trapped air will find the high point. So save the highest point for last.
Now if it's a keen pressure bleeder that pressurizes from the MC, then fuckitall. Crank up the pressure and blow that fluid across the garage from all ports at the same time, then close them off one by one and I'd think it's good to go.
When bleeding the brakes, make sure the bleed screws on the calipers are pointing straight up so there is no possibility of air bubbles getting trapped. If the calipers are mounted on an angle, you will need to unbolt one ear from the bracket. Pivot the caliper so it points straight up and place a spacer between the pads to prevent the pistons from coming out of the housing.
just ordered a fuel pump with autohausaz, they are a life saver for German ownership.
What I meant about "off the car" was unbolted but with the brake line connected...like,
turn upside down in your hand, bleed, then close off and flip over and do the other.
But as Joe and Morgan noted, since it shares the same reservoir you only need to do it from the
top one. I think even if sucking or pressurizing it wouldn't guarantee air not getting trapped in pockets
if you tried to bleed out the bottom, hence the suggestion not to bleed from there at all. LOL
just ordered a fuel pump with autohausaz, they are a life saver for German ownership.
What I meant about "off the car" was unbolted but with the brake line connected...like,
turn upside down in your hand, bleed, then close off and flip over and do the other.
But as Joe and Morgan noted, since it shares the same reservoir you only need to do it from the
top one. I think even if sucking or pressurizing it wouldn't guarantee air not getting trapped in pockets
if you tried to bleed out the bottom, hence the suggestion not to bleed from there at all. LOL
On the first one, I did all 4. Then I read all the data and just did the big one on the passenger side.
We lease server space from a Wells Fargo server farm that is 1.5 blocks from where AHAZ used to be.
11-30-2020, 08:41 PM
