Thanks a bunch for the tip regarding R1Concepts. I installed my new rotors today and after a 30 minute drive, the pads mated with the rotors.
I had a bit of pedal pulse for a while, but it all smoothed out.....





Also, while I had the front wheels off, I install the new Philips X-Treme halogen bulbs. They promise up to 80% more light. I will check them later tonight.....

 

Drilled drums are not so far fetched as you may think.
Probably being done long before some of you were alive..lol. Actually more effective on drums than discs really as drums really trap heat and can benefit way more than a disc ever would.

A quick search:
http://www.chtopping.com/CustomRod4/

 

I discovered that slotted disc rotors are directional. My picture above shows the rotors installed incorrectly.

I swapped the rotors this morning based on this info from Brembo....

"The discs should be installed such that the end of the slot nearest the outer edge of the disc contacts the pad first."

Hope this helps someone....

Cajun

 

GM marks the rotors -- which side they go on..

 

Unless the rotor is cast directional they remain universal regardless of the finish pattern or labels. To GMs credit they have produced some directional rotors in the past but I'm questioning the HHR market for this. The only common ones today seem to be on the Vette. There were some years ago however for the Impala/9C1 which were produced as directional also.

If these are truly directional 'hats off' to GM for doing so. They'd be only a GM produced part however and very, very unlikely such from an outside supplier.

To understand more about what makes a rotor directional here's a pic of a directional casting. This would be a right side rotor.



I've compiled quite a number of pictures over the years of rotor finishes- some good, some not so good. You can see them all here:
http://s122.photobucket.com/albums/o269/ToddTCE/Rotors/

 

Well you got me wondering Cajun, so I called R-1 and talked to tech support. I was told that I had my rotors installed correctly. I was doing google searches yesterday and a I saw them installed both ways in different applications. If you look at Hvrods pic which is a rear brake set up, it is turning the same direction as my rotors with the slots and vents angled to the rear.

However the R-1 guy said they would work in either direction but for maximum stopping power angled to the rear.

 

Heres the left disc..

 

So which direction should the slots be facing??? Any pics with them on right?? My feeble mind is not visualizing how they look correctly



Goose

 

Like was stated; it won't matter. That was the point of the link to various patterns and designs. I call it "builders choice". And of course as you'd expect each supplier makes claims to why theirs is superior.

As for "power", a rotors torque is calculated by it's diameter (combined with piston area for clamping and pad coefficient for friction) to produce total toque value. Slots, holes, dimples, vented or solid, even a pizza pan of the same size won't change the physics of the calculation for torque (power). Albeit your pizza might taste a bit funny the next time....

Choose whatever way makes you happy is all that matters. You'll note the pic link above shows the true design of a directional rotor. You'll note the castings internal air passages are such that they draw or suck air from the center eye of the rotor and vent it outward at the edge. That was the main point to convey.

 

http://www.zeckhausen.com/how_to_pro...all_rotors.htm

per this site found..
If the vanes are directional it matters..

if the vanes are Radial or Straight .. its up to you..