JackOlsen

I'm trying to find the replacement spec for width on these. Does anyone know?

Bill Verburg

30mm

ron mcatee

Jack , per the manual, they are 20mm thick with a mnimun of 18mm when resurfaced. If someone else has different data, please let Jack know.

Bill Verburg

That would be great information if Jack had 911 20mm rotors on his car, or in his pic for that matter

rusnak

Do stock 930s use floating rotors?

Edit: ok, nevermind. I don't know what he has on his car.

Bill Verburg

stock on a '78-80 930 front was floating 304x32 w/ a 911 hub. From '80 they changed the hub and rotor is a 1 piece 304x32 design

pictured in Jacks post is the '78-80 floater

Toby Pennycuff

Jack, I think I have the specs at home. I'll look them up tonight. Seems like I remember minimums to be around 28mm, but Bill may be correct at a 30mm minimum thickness. Hold on to your hat when you source these puppies. They are NOT cheap and are increasingly difficult to find. Ditto the calipers (but I'm sure you know that already!)

rfloz

If you find a place in So Cal that will Blanchard grind/machine(?) these, please post.

The Zimmerman's that PP has are not outrageous, at least a couple of years ago when I bought some.

Steve Weiner-Rennsport Systems

I would speak with George at Ollie's.

The '78-'79 floating Zimmermans are not cheap at $426/each but thats the only thing that fits the factory hats.

JMHO, but there are better options that are more durable and offer lower replacement costs. You might do some research about this unless you are stuck on the factory ones.

JackOlsen

Thanks. It's hard to believe it -- but I'm still in spec with my aging front rotors. I bought four of the front rotors back in the day when PCNA offered a PCA discount. But I don't want to put the second set on any earlier than I need to.

For the 78-89 930 rear rotors (28mm originally), would the replacement be 26mm?

Steve Weiner-Rennsport Systems

Yessir, that correct.

Toby Pennycuff

Jack,

Call Steve and ask him about his 930 rotors. He won't say much about it in public forums, but they are GREAT! I have them on my race car AND my 930. Won't buy anything else. Call him.

Toby

JackOlsen

I've heard nothing but good things about Steve's replacement rotors. But I'm still on the factory fronts that I put in back in almost a decade ago, and they're still in spec (in terms of cracking and thickness). Then I've got the second set I bought way back when sitting on the shelf -- which will likely give me another 10 years of use.

So I'm on board with the Rennsport plan, but I'm going to have to make sure I get them before Steve grows old and retires to a tropical island.

Big brakes. Light car. (And an average of 10 track events a year.)

rfloz

Thanks for the referral to Ollie's.

Oops! on the rotor cost. My T/L is an '84 with the non-floating rotors - much cheaper.

Ed Hughes

Gotta drive to Lake Havasu to visit Ollie's nowadays.