Oddball caliper

[davep]

I'm still trying to ID this caliper.

[gms]

looks a lot like an early 908/ 911S, do you have more pix?
is it aluminum?
GT Brakes (http://www.stazak.com/914/gt/brakes/brakes.html)

[JKH]

early version of the 908 caliper ? Do have both L&R ?
Ask Gunnar Racing,
http://www.gunnarracing.com/

[davep]

Yes I have several pictures, plus the actual caliper.
I have actually had a chance to closely examine the 908 or 914/6 GT caliper.
I have several "S" calipers but only the one oddball.
My thread on Pelican with a couple other shots:
http://forums.pelicanparts.com/showthread.php?s=&threadid=329280

[davep]

I have disassembled this caliper, and can confirm it is 48mm bore (standard), but has no pins for the piston retractors.

[Bernie B]

It looks to me like you have a 906 & 910 brake caliper identified by its unique U pin to retain the brake pads. The 908 & 914/6 GT caliper as shown in Jeff's photo incorporates a quick change system to retain the brake pads.

[davep]

Thanks Bernie. That does seem to nail it. I was never able to find such literature before. Do you have a copy of that manual? Seeing this I would like a copy also.

[Bernie B]

Dave- I have a very nice original owner’s manual that would be pretty pricy to copy. I think I have a "shop copy" that would be significantly less. I have a pretty full plate at the moment as we are taking two 935's to RennSport III. Let's talk in a couple of weeks.

Thanx, Bernie

[JKH]

quick change pin system

[Eric_Shea]

My assesment of this caliper (as it's been here at the shop for a while now) is that it is a 908 caliper for certain.

It does carry the 910 pin system which leads me to believe it is a very early 908 prototype caliper. This (910) pin was cumbersome and more than likely replaced with the simple solution we now know to be the 908 system. This caliper also has "V" stampings. Those are reserved for prototype applications (or so I'm led to believe).

Here's why it's not the 910:

1. Exact same specs. as the S-Caliper (which we know is the 908 caliper casting)
2. Same fluid inlet cover as the 908/S-Caliper. 4 bolt square fluid inlet vs. the 3 bolt round inlet on the 910 caliper.
3. 908/S-Caliper nose vs. 910 caliper nose. The 910 caliper nose "re-appeared" on the late model S-Caliper that has the green dichromate sealant. (1972.8). This is 908/Early S-Caliper all the way.

We're going to play around with a pair of early S-Calipers I have here to see if we can match the radius for the grind (the top has been ground down by 4mm, probably for 13" hillclimb wheels). The rest (pin and latch) should be easy to replicate. Now... all I need is a few extra hours in the day. ;)

[Eric_Shea]

I stumbled across the missing link today...

Amazingly it shows the progression from Dave's first version of the 908 caliper to the more common version.

Lots of little things to notice in this picture: