Front Caliper Orientation?
10-12-2012, 04:15 PM
#1
Burning Brakes
Thread Starter
Front Caliper Orientation?
I recently installed a pair of front calipers off of a '97 993 on my '82 928 (already had a '86.5 front suspension installed).
The 993 calipers are mounted on the leading (front) edge of the rotor while the 928 calipers are mounted on the trailing (rear) edge of the rotor. So, to make the 993 calipers work, I had to swap the bleed screws and cross-over pipes end-to-end. Otherwise, the 993 calipers bolt right up.
Since the conversion, I've been wondering why the 928 calipers are mounted on the trailing edge of the rotor while other Porsche's have the calipers mounted on the leading edge. Is it just packaging or is there a technical reason?
Anyone know the rational for the different placement?
James
The 993 calipers are mounted on the leading (front) edge of the rotor while the 928 calipers are mounted on the trailing (rear) edge of the rotor. So, to make the 993 calipers work, I had to swap the bleed screws and cross-over pipes end-to-end. Otherwise, the 993 calipers bolt right up.
Since the conversion, I've been wondering why the 928 calipers are mounted on the trailing edge of the rotor while other Porsche's have the calipers mounted on the leading edge. Is it just packaging or is there a technical reason?
Anyone know the rational for the different placement?
James
10-12-2012, 04:48 PM
#3
Burning Brakes
Thread Starter
Actually, I was just looking at photo's of the Panamera "Sport Turismo" and noted that the calipers on the Panamera are mounted on the leading edge. That's what spurred the question.
James
James
10-12-2012, 07:07 PM
#4
Rennlist Member
Join Date: Jul 2002
Location: Deep in the Heart of Texas!
Posts: 3,266
Likes: 0
Received 5 Likes
on
4 Posts
Only reason I can think of might be air flow for a particular car's underbody or clearance to suspension parts. My car has true Big Reds from a 993, and it was same thing, had to reverse the cross over tube and bleeders to flip the calipers for a 928 .... otherwise identical in every respect.
10-17-2012, 05:03 PM
#5
Burning Brakes
Thread Starter
Just saw some photo's of the new McLaren P1. The P1 also mounts the front caliper on the trailing side of the rotor (albeit clamping the lower portion of the rotor - as opposed to the 928 clamping the upper portion).
Any brake engineers out there who know the rational for the different caliper placement on different vehicles?
James
Any brake engineers out there who know the rational for the different caliper placement on different vehicles?
James
10-17-2012, 05:10 PM
#6
Rennlist Member
the orientation of the caliper on the rotor has no effect on stopping. The caliper could be mounted bottom center if they had wanted. It is an aethestic issue and a clearance issue for the other things in the wheel well.
10-17-2012, 05:12 PM
#7
Drifting
I would guess cooling has a bit of an issue with placement. Engineering wise they do the same thing, though the back up is either pushing or pulling depending on placement around the spindle and suspension axes, not sure that matters here though.
Other thought would be the positioning of the tie ro connection, in front of or behing the shock/spring.
Other thought would be the positioning of the tie ro connection, in front of or behing the shock/spring.
