993 brakes on Early hubs

[jgilliam914]

I am hotrodding a mid 85 911 with a 3.6 . I figured I would upgrade The brakes while I was at it .. I already have 993 black calipers and the adapter but was curious what rotors would I use??
The ones I have seem to be about a inch short of getting the full capacity of the pads and I think the 993 won’t fit on the early hub..
Thanks for your help

[Bill Verburg]

Originally Posted by jgilliam914

I am hotrodding a mid 85 911 with a 3.6 . I figured I would upgrade The brakes while I was at it .. I already have 993 black calipers and the adapter but was curious what rotors would I use??
The ones I have seem to be about a inch short of getting the full capacity of the pads and I think the 993 won’t fit on the early hub..
Thanks for your help

For the front use 32X304 annukus w/ a flat hat ala '78-79 930

It'll look something like this




in back use 930 28x307mm rotor and modify the caliers by plugging the oe mounting holes and redrilling to accommodate the rotors and clearance the throat area a tad
it'll look something like this

you will also need to ditch the stock backing plates

[turborat]

Bill,

For my ‘79 SC with 930 fender width, may I use the late 930 one piece front rotor on the OE ‘79 hubs or do I need to machine them in anyway? I’ve searched through quite a few threads on this upgrade topic and not quite found the answer to this question. I’m thinking there may be interference with the back of the rotor on steering or suspension components.

I have the ability to adjust wheel off-sets as needed. Track only car running 17” or 18” wheels. The upgrade packaged I’ve landed on is the 993 C2 calipers front and rear with 930 rotors front and back. Plenty of great info in that modification. Thanks, Paul

[Bill Verburg]

Originally Posted by turborat

Bill,

For my ‘79 SC with 930 fender width, may I use the late 930 one piece front rotor on the OE ‘79 hubs or do I need to machine them in anyway? I’ve searched through quite a few threads on this upgrade topic and not quite found the answer to this question. I’m thinking there may be interference with the back of the rotor on steering or suspension components.

I have the ability to adjust wheel off-sets as needed. Track only car running 17” or 18” wheels. The upgrade packaged I’ve landed on is the 993 C2 calipers front and rear with 930 rotors front and back. Plenty of great info in that modification. Thanks, Paul

In '79 the oe setup for an SC or Carrera was the narrow 911 hub shown above

For '80 up on 930 and later M491 t-look cars the wider late hub is used w/ the later one piece 930 rotors, in '78 & 79 930 used the multi-piece 930 rotors

So on you '79 SC iff you have 930 fenders, yes, you can use the wider late 930 hubs but you will also need the late 930 1 piece rotors

Each setup is a system that rely's on the other parts to work well w/ a given chassis

late 930 wide hub & 1 piece rotor



'78-79 930 multipiece rotor/hat assembly w/ 911 hub, 930 would also have a 21mm spacer to move the wheel out,911 would not use the spacer

[turborat]

Originally Posted by Bill Verburg

In '79 the oe setup for an SC or Carrera was the narrow 911 hub shown above

For '80 up on 930 and later M491 t-look cars the wider late hub is used w/ the later one piece 930 rotors, in '78 & 79 930 used the multi-piece 930 rotors

So on you '79 SC iff you have 930 fenders, yes, you can use the wider late 930 hubs but you will also need the late 930 1 piece rotors

Each setup is a system that rely's on the other parts to work well w/ a given chassis

late 930 wide hub & 1 piece rotor



'78-79 930 multipiece rotor/hat assembly w/ 911 hub, 930 would also have a 21mm spacer to move the wheel out,911 would not use the spacer

Ok! Thanks for reply. To be clear, cannot use the narrow SC hub with late one-piece 930 rotors. Correct? I’ll have to either source late 930 hubs or use the early multi-piece 930 rotors on the narrow SC hub. Correct!

[Bill Verburg]

Originally Posted by turborat

Ok! Thanks for reply. To be clear, cannot use the narrow SC hub with late one-piece 930 rotors. Correct? I’ll have to either source late 930 hubs or use the early multi-piece 930 rotors on the narrow SC hub. Correct!

correct

[Harpo]

Will the 993 calipers fit under my fuchs? Currently I have 15's but I'm planning to change over to 16's. Who makes a 993 adapter for the front brakes?

[Bill Verburg]

Originally Posted by Harpo

Will the 993 calipers fit under my fuchs? Currently I have 15's but I'm planning to change over to 16's. Who makes a 993 adapter for the front brakes?

15s no

16s probably

I used 964 on 930 rotors under 7 & 9 x16 Fuchs and when I measure the current 993RS(which are bigger than 993) under 17s it looks like they might fit 16s but it wold be very tight

I think that 993 caliper adapters for 993 front calipers s on 304x32 rotors on 911s are available form VCI, Rennline, Rebel and maybe Tarett

[Harpo]

So far Stompski, rennline, Tarett and Rebel Racing (996 + boxter only) don't have 993 adapter brackets. I have not yet heard back from VCI.

[Harpo]

Elephant Engineering and VCI do carry the brackets

[Harpo]

Lindsey might also have a adapter bracket


https://www.lindseyracing.com/LR/Porsche/993-351-900-00.html