Brakes: 993 to 911 caliper adapter dimensions?

[smdubovsky]

What are the caliper adapter dimensions to mount a 993 caliper on a 911 strut (using a 930 rotor)? This was posted once somewhere, but I've search for almost an hour and can't find it. The hole-to-hole dimensions are obvious, but how far are the holes from the edge of the adapter? Specifically:
1) How far from the caplier mounting edge are the strut (3.5") holes?
2) How far from the strut mounting edge are the caliper holes?

Here is the only pic I can find (which are boxster caliper adapters - but the idea is the same).



Thanks,
SMD

[smdubovsky]

Bump. Anyone?

Tnx,
SMD

[jpnovak]

I posted some in here for a 993TT set. The 993 would be similar but slightly narrower.

951 caliper modifications

[boyt911sc]

SMD,

I was in similar situation awhile back. Totally confused what adaptor/s to use with my 993 calipers. The dimension of the adaptor is determined by your brake rotor selection.

From your 993 calipers decide or select which brake rotor type you want to install. Then find a suitable adaptor and this is usually custom-made for a particular set-up. Otherwise have a machine shop fab one for you.

Finally decided to go to Probraking Kit for 993 caliper on SC's. One of the 4 options Mr. Brake Guru recommended to me. Hope this will help you.

Tony

[smdubovsky]

jpnovak,
Thanks, That might have been the thread I was remembering. Unfortunately (for me) it only covers the 993tt and 968 caliper adapter dims.

Tony,
Sorry. I thought almost all used the 930 rotors w/ the 993 calipers, but I can see how I should have been specific. I can mill my own adapters, but it wold be nice to make them before hand. I figured I could avoid reinventing the wheel since SOMEONE must have measured these things before they installed them.

Thanks,
SMD

[jpnovak]

I think the only differences are the relative width of the adapter. This will control the centering of the caliper on the rotor of choice. The other dimension is the thickness of the adapter relative to the strut mounting holes. This will control the pad placement for a given rotor diameter.

I agree. Someone must have measured their adapters.

That thread also has dimensions for a 996 caliper adapter.

btw, in another thread about 996 calipers you mentioned having a set to play with. Can you tell me what the throat width is? I am curious how wide of a rotor will fit inside the caliper. I wonder if a 930 rotor will fit with the shaving of the nubs like a 993 caliper. A good comparision would help since you seem to have both. I expect that 996/boxster S calipers will start showing up on the used market cheap. There are a lot of those cars on the road, some of them must end up going off-road.

[smdubovsky]

jpnovak,
Surfing the VCI site, it looks liek the adapters are the same for the 993tt and S4 calipers. The S4s are the same "big blacks" as the regular 993 right? If thats the case, your post DOES have all the info I need. Thanks!
SMD

Edit: I posted this reply as you were replying. Yes, I have both 996 and 993 calipers. I will try to measure the throat and take some comparison pics tonight. I have 930 R rotors already, and have bought a used set of used F 930 hubs&rotors from a fellow pelican. Don't have them yet to see exactly how much work would be required to fit them in the 996 caliper, but I can take some good measurements...

[boyt911sc]

SMB,

This is the test and fit jig set-up I made for the 993 calipers on SC.


If you want to borrow this for your project please contact me at ATD911@hotmail.com. Got the parts from fellow Pelicanites.

Tony

[SPINNY]

I looking for the same info, but for 993 rotors

[JeremyD]

I think KTL did the measurements

993 Caliper Mods- Grinding and Drilling

[DinFtown]

Originally posted by SPINNY
I looking for the same info, but for 993 rotors

You can't use 993 rotors it must be 930, or aftermarket two peice rotors on this hub if you want it done the safe way.

[SPINNY]

can you turn down a stock hub to use 993 rotors?

[ssetek]

yes thats what i did

[DinFtown]

Please do not turn down your hub...
This is very dangerous. The 911 hub is not the strongest thing in the world, and I have seen hubs that have not been weekend by removing material crack, and brake into pieces. Machining your hubs is only going to make the chance of this happening to you much greater. Can you imaging going down the road at a good speed taping your brakes to find your hub cracks and breaks in two... there goes your car, as the wheel hub pieces, and whatever else it all manage to rip off our cars all goes the other way.

If you are dead set on using only 993 parts, as in rotors, and calipers on your car the only way to do it is replace the whole hub. I can't think of the name but a company dose make replacement billet CNC machine hubs ($$$$$) for the 69-89 911 that uses the 993 front rotors, but that is the only safe way of doing it. Other then that do not atempt to use the 993 rotors in the front of you pre 89 car as you are tempting the fait of your car. I know I have seen some of the pictures on here of cracked front hubs, do a search or ask Bill V. about it if you want a second opinion. The after market two piece rotor setups are not that expensive, especially when compared with the risk you are taking weakening your hubs by turning them down.


Dave

[Bill Verburg]

The adaptor for 993/928S4 and 993t/993RS calipers is the same in all respects. The difference is in the rotors, the Big Red is ~10mm taller and uses a commensurately larger rotor( otherwise the pad hangs over the edge of the rotor)

The 993 caliper is usually used w/ a 304 -310mm x32mm rotor, the 993tt w/ a 322x32mm rotor.

As Dave mentioned the 911 hub is none to strong to begin w/ I wouldn't machine it down.

2 piece hat/rotor sets are lighter and more thermally efficient.

If you want a stock parking brake the one piece 930 or 993tt are the only rear ones that work right, 993tt needs extensive modification.