914-4 rear brakes with vented rotor, does anybody have/make/sell the spacers? Options

[jim912928]

Hi, I've read many threads on rear brake conversions. I just happen to have a pair of vented rear rotors off a 71 that are in excellent shape. I also have relatively new 914 rear rotors that I can have drilled. I've read where people have had spacers made so they can use their existing rears with vented rotors. Does anybody make these or have some? Or do I need to just find a place that can do them one-off? Or, I may just drill out my existing rotors for 5-lug. Just looking for easy options!

Thanks in advance,

Jim

[davep]

I just did a little checking. The rotor diameters are different, so some turning of the rotors will be needed.
914/4 rear 282 mm
914/6 rear 286 mm
911 vented 290 mm
I have used the 914/6 rotor with 914/4 calipers without problem.
I have used the 911 vented rotor with 914/6 calipers.
The 911 vented rotor will not fit in the 914/4 caliper without some machining. There is not enough material in the 914/4 caliper to consider grinding it to fit. Allow enough clearance for the rotor to grow when it is hot. I would be inclined to reduce the diameter to 282 mm. Excess diameter does nothing for you. The pads do not work out there, it is extra unsprung weight, and a greater flywheel effect.