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> Boxster Brakes, Which to get? S or Non S?
soloracer
post Mar 18 2007, 11:51 PM
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I am looking for a decent brake solution for my 914. Currently the car has an 80's 911 front suspension and I purchased a set of 964 C2 calipers and Carrera rotors. I thought I was doing good until I saw the bolt spacing for the 964 calipers don't match the strut mounts. I found adapters but they require sawing the mounting tabs off the calipers and buying an adapter - to the tune of $1000+. So now I am considering selling the 964 calipers and going with a full set of Boxster units. Question is though, which ones do you go with? The Boxster S or non S? Or should I just scrap the idea of Boxster brakes all together and get 993's or something else? Maybe keep the 964's and redrill the holes? Know anyone who does that sort of work?

Any and all suggestions are appreciated.
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Brando
post Mar 19 2007, 12:05 AM
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930 (big reds), 964 and 993 brakes are 3.5" bolt hole spacing. So, you'd have to weld an adapter on for those anyhow. As for Boxsters... I think they are 3.5" spacing as well, but I'm not 100% sure.
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DanT
post Mar 19 2007, 12:21 AM
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are you sure your struts/spindles are off of an 80s 911? they should be 3.5 spacing, just like the C2 brakes.
or is your problem getting the caliper to center on your rotor? You may have to go to another Porsche rotor. I know when we did a "big black" up grade to a C2 a while back we needed an adaptor to get the big blacks mounted (they mount radially instead of axially like the C2 stock brakes) and we also had to use 928 S4 rotors to work correctly with the calipers.
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Aaron Cox
post Mar 19 2007, 12:25 AM
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im working on a non s swap right now...
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smdubovsky
post Mar 19 2007, 07:49 AM
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QUOTE(Brando @ Mar 19 2007, 02:05 AM) *

930 (big reds), 964 and 993 brakes are 3.5" bolt hole spacing. So, you'd have to weld an adapter on for those anyhow. As for Boxsters... I think they are 3.5" spacing as well, but I'm not 100% sure.


930s are NOT big reds. They have 3.5" spacing. Bolt right on w/ early (<1980) turbo rotors.
964 have to have the caliper machined + adapters. W/ adapters, you can have any bolt spacing you need. (Note: I've never held one of these, just the information I gather from pelican and the pics)
993/S4 calipers require adapters but no machining. Use early (<1980) turbo rotors. (I've got a set of these on my bench)
Boxster calipers require adapters but no machining. Use carrera(84-89) rotors. Most say this is no real upgrade vs carrera calipers (though you can put boxster calipers on 3" struts becasue of the adapters)
Boxster S are 996 brakes. They also require adapters. No early rotor fits them easily. (I also have a set of these on the bench)

SMD
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Aaron Cox
post Mar 19 2007, 09:28 AM
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QUOTE(smdubovsky @ Mar 19 2007, 06:49 AM) *

(though you can put boxster calipers on 3" struts becasue of the adapters)


SMD

wrong... no one makes an adapter for 3".... and the ears get in the way of pad's and any adapter block....
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smdubovsky
post Mar 19 2007, 10:54 AM
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QUOTE(Aaron Cox @ Mar 19 2007, 11:28 AM) *

QUOTE(smdubovsky @ Mar 19 2007, 06:49 AM) *

(though you can put boxster calipers on 3" struts becasue of the adapters)


SMD

wrong... no one makes an adapter for 3".... and the ears get in the way of pad's and any adapter block....


I'll have to defer to your experience Aaron. I only have late struts. Are the 3" ears in a different location on an early strut? I've never studied one closely, but it appears they are just closer together. Why wouldn't the same tangential/radial adapter design principle work?

You are right - I have never seen an early 3" adapter 'off the shelf'. I always assumed because of the limited market and the relative ease of swapping to 3.5" struts.

SMD
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Aaron Cox
post Mar 19 2007, 10:59 AM
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craig downs and i are working on it.

this pic should show how everything gets in the way (IMG:style_emoticons/default/smile.gif)
they fit under all 15" rims i own, cookies, fuch's, BBS 15x6, 7 and 8


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Van914
post Mar 19 2007, 12:42 PM
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Call Rich Johnson in Texas. He make adapters. I do not know if he has them for 3" spacing on your struts. He may be able to make you a set.
Van914

Aaron, enjoy the rear adapters. Post some oictures when you are done.
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Aaron Cox
post Mar 19 2007, 12:44 PM
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QUOTE(Van914 @ Mar 19 2007, 11:42 AM) *

Call Rich Johnson in Texas. He make adapters. I do not know if he has them for 3" spacing on your struts. He may be able to make you a set.
Van914

Aaron, enjoy the rear adapters. Post some oictures when you are done.


Rich was the first guy i asked before mocking up the 3" setup above.., there is physically no room for an adapter on a 3" strut.... you have to mill off the ears, weld up a little thickness, mill it flat.. and THEN make an adapter.

Van - i sure will!
your wheels shipped this AM.
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ClayPerrine
post Mar 19 2007, 12:51 PM
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If you use 16 inch wheels and the adapters for the rear, plus carrera rotors, you can put them on the front. But it won't fit under 15" wheels.


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Aaron Cox
post Mar 19 2007, 12:54 PM
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QUOTE(ClayPerrine @ Mar 19 2007, 11:51 AM) *

If you use 16 inch wheels and the adapters for the rear, plus carrera rotors, you can put them on the front. But it won't fit under 15" wheels.


that is the kicker - yep, rear adaptors on the front might get ya there.
gotta use 24mm thick carrera rotors anyway (IMG:style_emoticons/default/smile.gif)

clay - with 16" wheels, would that put the caliper too far outboard and not use all fo the pad on the rotor? - ie overhang?
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ClayPerrine
post Mar 19 2007, 12:59 PM
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QUOTE(Aaron Cox @ Mar 19 2007, 01:54 PM) *

QUOTE(ClayPerrine @ Mar 19 2007, 11:51 AM) *

If you use 16 inch wheels and the adapters for the rear, plus carrera rotors, you can put them on the front. But it won't fit under 15" wheels.


that is the kicker - yep, rear adaptors on the front might get ya there.
gotta use 24mm thick carrera rotors anyway (IMG:style_emoticons/default/smile.gif)

clay - with 16" wheels, would that put the caliper too far outboard and not use all fo the pad on the rotor? - ie overhang?



I don't know. I discussed this with Wes one time, but we never pursued it. It is too easy to get the struts with the 3.5 inch bolt spacing.


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smdubovsky
post Mar 19 2007, 01:57 PM
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Aaron,
That pic says it all. Tnx. The holes still looks to be in the same relative position to the 3.5" ears. I wonder if all the boxster adapters floating around move the caliper out radially like you mention and let the pads overhang. Not so good...

QUOTE
It is too easy to get the struts with the 3.5 inch bolt spacing.


Im w/ Clay here;)
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soloracer
post Mar 19 2007, 02:32 PM
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Just to be clear, everyone here is talking about non S calipers correct? What would the difference be with using S calipers? Do you need 28mm rotors? Will 24 mm work? Do they mount the same? Since I have 17" wheels I know mine will fit.
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smdubovsky
post Mar 19 2007, 04:02 PM
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Yes, we're talking non-S.

The S/996 calipers take a goofy rotor (318x28). AFAIK, Nothing from porsche is going to fit. A 951 rotor MIGHT do it (299x28) if you are carefull to align the caliper just right to avoid overhang. I heard the OD of the hub can be turned down to fit a 951 rotors (but thats just what I hear). If you make custom hats, I suspect an aftermarket rotor could be found (but its a lot of freakin work;) Look up 996 calipers on here or pelican - Bill verburg and I had a discussion w/ lots of dimensions and pics. Someone here made 996tt calipers fit, but they machined down an aftermarket rotor.

FWIW, a 930 or 993 brake setup (both are 304x32) will yield more heatsinking than a 996 and far easier to fit.

SMD
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Luke M
post Mar 19 2007, 06:01 PM
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I have boge 3.5" spacing struts, with carrera rotors, non-s boxster calipers, and spacers all fits under a 15"wheel.


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Aaron Cox
post Mar 19 2007, 06:08 PM
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yep... that looks like the TRE kit. thats the bolt on approach...
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craig downs
post Mar 19 2007, 08:23 PM
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With that pic even with the 3.5" spindle and the adapters the calipers are still not all the way in . Looks like they have a overhang to
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LarryR
post Mar 19 2007, 08:48 PM
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QUOTE(Aaron Cox @ Mar 19 2007, 11:44 AM) *

QUOTE(Van914 @ Mar 19 2007, 11:42 AM) *

Call Rich Johnson in Texas. He make adapters. I do not know if he has them for 3" spacing on your struts. He may be able to make you a set.
Van914

Aaron, enjoy the rear adapters. Post some oictures when you are done.


Rich was the first guy i asked before mocking up the 3" setup above.., there is physically no room for an adapter on a 3" strut.... you have to mill off the ears, weld up a little thickness, mill it flat.. and THEN make an adapter.

Van - i sure will!
your wheels shipped this AM.


Any Idea when your s adapters will be ready and the cost?
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