Upgrade to 930 Brake: Questions and Problems

[82SC]

Well I have been doing some research with the help of Bill Verberg and Vehiclecraft and Rennsport Sysyems about this desirable upgrade...

But I have been quoted 3000-4500!!!
Wow...I can get big red or 993/S4 brakes for less!!!

So I have basically found out that the custom work on the calipers is unavoidable...the OEM stuff like the rear rotor, brake lines, pads, fluid, master cylinder I am planning to get from Pelican or course...

But those pesky front rotor are unavoidable...they are custom and they are a chunk of the price...nearly 800 for the set.

So I have trying to see if any of you have ideas of how to source these from somewhere else....

Rennsport systems uses Brembo...I wonder if I can buy the rotor from someone else in that dimension and add their custom hats only...

What about having a machine shop make the hats...it is a plate of metal with a big hole in the middle and a bunch of holes for the screws...

Not that I want to take away their profits and business...but 300 bucks for a non-OEM part that is just a sheet of metal...on top of the already expesive calipers makes my blood boil...and 800 for a pair of rotors!!!!

I guess there are flat 930 rotors (917/935) that can be used too, but they are just as pricey...

Any one want to do some research together about different options and come up with a solution???

www.vehiclecraft.com has a great explaination on how the calipers are customized

[rattlsnak]

Hey there,. I have been researching the same thing for months, and you are right, Big Reds are much cheaper than stock 930 stuff. I have an SC body as well, and have found --through MUCH investigating, including Bill V, and VCI, etc-- that I can piece the whole set together for @ 2,500 using all factory parts except for the hats and adapters. Not a bunch different from your quotes, because there simply isnt that much mark-up in this stuff. The most expensive part is getting the rear calipers machined to fit the adapters. As I stated im just beginning to get some of the parts in, so Ill let everyone know what I came up with in a few weeks.

[Bill Verburg]

Steve Timmins is offering a nice alternative for the front using oem 993 tt rotors and Big Reds ~$1500 for the fronts + pads and lines.

http://www.instant-g.com/Products/BigRed/index.html



The rear is relatively easily done just get some oem 930 rotors and 993 rear calipers. The mods can almost be done at home for this rear combo.

[Jack Olsen]

Pelicanite Dave Bouzaglou's shop did the installation on my 930 brakes. I found a very fresh (and cheap) pair of 78-79 front rotors in the rennlist classifieds, and his shop provided the custom hats. You might want to give him a call to see what he can source for you, since it looks like you're also in Los Angeles.

I paid $650 for the set of four 930 calipers, if memory serves. So the whole deal can be done pretty affordably. You also might want to consider the C4/951 brakes Bill Verburg put on his car. (I've got a set of those I'm looking to sell.)

[82SC]

how did you find a set for so cheap!!!! Calipers I mean.
Plus I want to stick with Fuchs so the Big reds are not an option.

And what do you mean by custom hats?
I thought the front 78-79 Rotors were flat no?

What did you do about machining and the rest???

Thanks

MJ

[RarlyL8]

Stephen Kaspar of ImagineAuto had a complete 930 brake setup that he took off of "Monster" for its' latest overkill update. The package might still be available. I believe he quoted me under $2000 for everything. Not something I need just yet. Contact info is at: www.imagineauto.com

[Jack Olsen]

I got the calipers from a guy in Singapore, same place I got the 7x8x16 Fuchs for $450. I wish that guy had more parts I could use. The shop did all the machining. The 78-79 rotors were floating, but the hats make them fixed for this application. You can see a little of the work here (click for a larger image):

[Kahuna]

i always thought that those calipers and rotors were a bolt on for the front and that only the calipers required mods in the back, No?

[82SC]

well from what I understand the rears are the bolt ons the fronts need flat rotors and the calipers have to be moded all around

MJ

[Bill Verburg]

In the front, 78-89 930 calipers are a bolt on to 911 struts with 3.5" ears. The floating front rotors are a bolt on to a 911 with oem 930 hubs/hats. They will bolt to standard 911 hubs with custom flat hats. Either floating or non-floating. The hats that Dave B. made are just high strength al. properly machined to accept the rotor and hub, there is no offset involved. Any competent machine shop can do it.

The rear rotors are a bolt on. The rear calipers need work to bolt onto a 911 trailing arm. Perhaps Jack can post some pics of his setup in the back.

The 964/993/993tt etc calipers are much more difficult in the front but easier in the back. The same rotors as used with the 930 calipers should be used, all comments about them are the same. There is the additional option of a 322x32 mm rotor in the front when the 993(S4) or 993tt(Big Red) caliper is used. The machining in the front and the caliper adaptor are very specialized. I would not trust too many machine shops to do the work as specialized numerical control programs are required. Any of the Brembos can easily be adapted to the back of a 911 as long as the 930 309x28 mm rotor is used. You retain the parking brake and the rotor is a straight bolt on. The only caliper mods are simple, the main one can be seen in my post above. The oem mounts need to be plugged and redrilled a bit closer together.

[82SC]

Jack's setup does not look as machined as I thought. On vehicle craft they have pics of the machining and they grind the lettering and fins (cooling!!) down pretty far....

is this necessary? I know redrilling the holes are...

http://www.vehiclecraft.com/Brakes/930T_mod.htm

the grinding actually looks pretty severe


Also if I had a shop machine me a rotor...what would I have to do to make the hat floating or not...and what do you use to attach the hats and rotors??

[pbs911]

http://cgi.ebay.com/ebaymotors/aw-cgi/eBayISAPI.dll?ViewItem&item=597875815

[Jack Olsen]

For clearance with 15-inch or 16-inch Fuchs, on the rears, at least, machining the fins down makes sense. The pictures of my fronts do not show the 1/4-inch spacers needed for the Fuchs to clear the calipers. With those in place, no machining was needed. In the back, everything was very tight on my car, but appeared to fit. On the track, though, there was enough wheel flex for me to get some contact between calipers and wheels, so we went back and machined off the outer fins.

Every car is a little bit different, though, so YMMV. Bouzaglou's shop has also done the rears with a different mount altogether, putting the calipers behind (instead of in front of) the axles. Some guys prefer it this way, I guess.

Here's one of my rear calipers, before the final machining was done:

[Bill Verburg]

The rotors need no machining. the difference between floating and non is in the method of connecting the rotor to the hat. Floating rotors use slots on the inner circumference of the rotor, a 't-lock' nut(item #4& 5) is used with an inner ring(#3) and outer lockplate(#2) which allows for a slight amount of radial and transverse movement of the rotor relative to the hub. This allows the rotor to run true to the pads(cooler) but is relatively noisy for street use.



A non floating rotor can have the same slots but have t-locks that have no play. Thus the rotor is not allowed to float. Alternatively the rotor can have holes tapped into it (in lieu of slots)which are used to solidly fix its position relative to the hub.

[82SC]

Jack: Are you running what wheels are you running? 8" or 7" with that 1/4" spacer? Does your front wheel extend past the arch? I am guessing a 7" with spacer is the prefered setup to avoid overly extending rims. And 8" or 9"'s on your rears?
I wonder what combination would be best with SC...or is it safe to assume that wil your flares etc...your wheel well dimensions are the same as an SC...

Bill: you should just make a powerpoint presentation about brakes...actually it would nice to have a brakes explained and brake upgrade tech article...Wayne is always keen on adding things like that...you are the brake guru...

Here is some info I collected just for reference when people seach on this subject:

Does not matter the rim type (944 Fuchs or 911) front either need machining and a small spacer or no machining and a larger spacer. The Carrera 5 spoke with arching rims can be used with no spacer and no machining

930 SETUP (911 Fuchs 7" or 8" on front; 8" or 9" on rear)
FRONT
930 caliper modified new mounting holes old mounting hole ground off
930 front rotors 304x32mm need to be flat (custom machining) can be floating or non. Either a brembo rotor, custom rotor or a 917/935 OEM 78-79 full floating Zimmermans
OE short lines
Probably need a spacer for clearance
May need to machine off cooling fins depend on spacer size

REAR
930 calipers need same mounting hole mods
930 rear rotors 309x28 are bolt on
Short lines (custom)
May need to machine fins or use spacer

upgrade master cylinder Mercedes 23mm for non boosted brakes and OEM 930 for boosted brake cars

Bruse Anderson also talks about changing the pedal assembly with one that has dual cylinder? Doesn't seem like that is necessary

hmmm anything I am missing

[Bill Verburg]

The dual mc is only necessary where basic bias is incorrect. If you use the 78-89 caliper f/r basic bias is great. It can be more tricky with the newer Brembos because the they came in three different sizes with variations in piston size which are not externally visable.