Brake Rotor Manufacturers

[Sheldon S.]

As I am getting closer to doing the brakes on my 71 resto, I pulled the original rotors out and measured them. They all have been turned at some time I suspect and they all measure 1.21 give or take a thou or so. Now I am in the market for some new rotors. Since they are a bit heavy for shipping to Canada I am trying to find s replacement here in Canada. Napa has several different qualities of rotors. Has anyone tried any of them? Are they similar in looks to originals or do they judge them? Does GM make a replacement still, if so does anyone have a part number and how do they rate? Any other suggestions greatly appreciated.
Thanks
Sheldon

[Joe L.]

Re: Brake Rotor Manufacturers

As I am getting closer to doing the brakes on my 71 resto, I pulled the original rotors out and measured them. They all have been turned at some time I suspect and they all measure 1.21 give or take a thou or so. Now I am in the market for some new rotors. Since they are a bit heavy for shipping to Canada I am trying to find s replacement here in Canada. Napa has several different qualities of rotors. Has anyone tried any of them? Are they similar in looks to originals or do they judge them? Does GM make a replacement still, if so does anyone have a part number and how do they rate? Any other suggestions greatly appreciated.
Thanks
Sheldon

Sheldon-------



OEM type rotors once available through the GM parts system are long-since discontinued. However, rotors are still available through the GM and Delco parts system. Basically, these are aftermarket rotors in Delco boxes. The best of those available in a STOCK-TYPE rotor (i.e. no "grooving" or "drilling") are GM #19174916, aka Delco 18A102, front, and GM #19174915, aka Delco #18A101, rear. These are actually quite economical at well under 50 bucks, each.

As far as I know, all of the Delco rotors, as well as most of the other aftermarket, no longer have the machined-in reliefs for the rivet heads or the rivet holes. There may be some specialty-type rotors out there that do, though. The lack of this feature cannot be discerned when the wheels are mounted on the car, so there should be no judging penalty.

As far as quality of these rotors or country of origin, I don't know. I believe there are some situations in which the castings are manufactured off-shore and the rotor machining is done in the US or Canada. However, keep in mind that brake rotors are a serious, safety-related component. For product liability reasons alone, I wouldn't think that any of the rotors supplied in the boxes of major parts manufacturers would be a problem.

[Gary R.]

Re: Brake Rotor Manufacturers

Sheldon,
As Joe said, finding rotors that have the rivet holes may be a problem. I have them but have to order them as the local NAPA's and supply houses don't have them with the holes. I use the holes to bolt on & dial in the rotors as well. I have used all types of rotors, GM,NOS GM, new aftermarket-both USA & Imported,slotted, drilled,slotted & Drille, Cyro treated,etc.
NOTE: I have faced spindles to .0000-0003" and installed rotors, ALL of them had runout. Some as little as 005" most over 008". 005 is not good enough for me so unless the rotor & spindle bolted or riveted then faced you will probably need to address runout.

[Jim T.]

Re: Brake Rotor Manufacturers

As I am getting closer to doing the brakes on my 71 resto, I pulled the original rotors out and measured them. They all have been turned at some time I suspect and they all measure 1.21 give or take a thou or so. Now I am in the market for some new rotors. Since they are a bit heavy for shipping to Canada I am trying to find s replacement here in Canada. Napa has several different qualities of rotors. Has anyone tried any of them? Are they similar in looks to originals or do they judge them? Does GM make a replacement still, if so does anyone have a part number and how do they rate? Any other suggestions greatly appreciated.
Thanks
Sheldon

Reference you resto on your 71, money spent on doing the right thing will give you thousands of miles of excellent braking if you do not have excessive rotor runout. If you are going to trailor your car and not drive it excessive runout will not be a problem, the rotor rotation has to move the caliper pistons in and out to pump air.
Recommend checking out www.bairs.com to see if you like their services. They can sell you new rotors and rivet them to hubs and your rear spindles with the runout corrected after the rotors are assembled to the front hubs and rear spindles.
Bairs corrected my rear rotor runout problem and several years of frustration of air in the rear calipers. They sold me good used rotors, riveted them to my 70's spindles, and trued them over 20 years ago. No more problems. My 70 continues to have excellent brakes.

[Sheldon S.]

Re: Brake Rotor Manufacturers

Is there any problem with using say the GM rotors and drilling them out for using the recessed allen screws to bolt the rotors to the hubs?
Thanks
Sheldon

[Joe L.]

Re: Brake Rotor Manufacturers

Is there any problem with using say the GM rotors and drilling them out for using the recessed allen screws to bolt the rotors to the hubs?
Thanks
Sheldon

Sheldon-------


I don't think that there would be any problem created in doing this. I fully expect that the "hat" thickness on the current rotors is the same as the originals. You can easily check this to be sure.

As a matter of fact, if using the countersunk-type, internal hex head machine screws to secure the rotors to the hub/spindle, I think you're better off starting with the "no rivet hole" rotors. With the type designed for rivets, the rivet relief is not the "best way to start" if performing a countersink for the machine screws.

The important thing will be to get the rivet holes drilled in precisely the correct location to align with the holes in the hub/spindle. The best way would be to use the hub or spindle as the "drilling guide".Then, countersink the holes with a correctly tapered countersink for the machine screws used.

If one wanted to create reliefs in the rotor hat, as original, for the installation of rivets, that's another story. In that case, it would probably be a machine shop operation that would cost you more than the rotor was worth. If one wanted to use rivets, I'd suggest seeking out rotors with the original style reliefs and rivet holes.