Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

> Rear 5-lug rotor and caliper - identify?, Just want to make sure what I've got before I order pads
chmillman
post Nov 5 2025, 09:48 AM
Post #1


Member
**

Group: Members
Posts: 202
Joined: 15-June 24
From: Switzerland
Member No.: 28,183
Region Association: Europe



As per previous threads, my car has had a 5-lug conversion - I think correctly done. The front hubs/rotors/calipers are 914-6/early 911 ones as far as I can tell (ATE calipers), I therefore assume the rear hubs/rotors/calipers might also 914-6 or similar? Can someone confirm? TIA

Attached Image

Just for laughs, Google's Ai analysis of the photo tells me it's from a Nissan Primera P12... (IMG:style_emoticons/default/lol-2.gif)
User is online!Profile CardPM
Go to the top of the page
+Quote Post
 
Reply to this topicStart new topic
Replies(1 - 7)
peteyd
post Nov 5 2025, 11:27 AM
Post #2


Senior Member
***

Group: Members
Posts: 740
Joined: 27-March 08
From: Elora, Ontario, Canada
Member No.: 8,858
Region Association: Canada



those are 4 cylinder calipers. later ones with the dual bleeders.
User is online!Profile CardPM
Go to the top of the page
+Quote Post
chmillman
post Nov 5 2025, 04:12 PM
Post #3


Member
**

Group: Members
Posts: 202
Joined: 15-June 24
From: Switzerland
Member No.: 28,183
Region Association: Europe



OK, so they changed the hubs and rotors for 5-lug… but the 5 lug rotor has basically the same dimensions overall as the 4-lug one, so it fits with the stock -4 caliper? Is that how it works?
User is online!Profile CardPM
Go to the top of the page
+Quote Post
brant
post Nov 5 2025, 04:21 PM
Post #4


914 Wizard
**********

Group: Members
Posts: 12,092
Joined: 30-December 02
From: Colorado
Member No.: 47
Region Association: Rocky Mountains



QUOTE(chmillman @ Nov 5 2025, 03:12 PM) *

OK, so they changed the hubs and rotors for 5-lug… but the 5 lug rotor has basically the same dimensions overall as the 4-lug one, so it fits with the stock -4 caliper? Is that how it works?



pretty close...
if you stay with non vented rotors... the OD of the 5bolt rotor gets turned down a tiny amount... to work on a 4 cylinder set up.
User is online!Profile CardPM
Go to the top of the page
+Quote Post
chmillman
post Nov 6 2025, 05:53 AM
Post #5


Member
**

Group: Members
Posts: 202
Joined: 15-June 24
From: Switzerland
Member No.: 28,183
Region Association: Europe



QUOTE(brant @ Nov 5 2025, 11:21 PM) *

pretty close...
if you stay with non vented rotors... the OD of the 5bolt rotor gets turned down a tiny amount... to work on a 4 cylinder set up.


OK, that's interesting, thanks... Just trying to understand all what has been done here. The disc does have a part number on it - 901 352 401 18 - and it does appear to be a 914/6 disc...

Attached Image

Attached Image

The OD of the rotor part is around 285mm (11.2") as well as I could measure while still on the car. From the traces on the edge of the rotor, it appears that it might even be rubbing slightly on the spring clip... So maybe these weren't turned down?

Attached Image

Anyone have the outer diameter specs for a /4 rear disc vs a /6 disc? Doesn't look like much could or should be turned off, the pad-swept area on the rotor starts in about 3mm from the outer edge.

Also have been unable to find a part number on the rear caliper, just the ATE logo... Here's what it looks like from the inside. Definitely dual bleeder fittings.

Attached Image
User is online!Profile CardPM
Go to the top of the page
+Quote Post
mate914
post Nov 6 2025, 05:58 AM
Post #6


Matt
***

Group: Members
Posts: 911
Joined: 27-February 09
From: Eagles mere, PA
Member No.: 10,102
Region Association: North East States



914-6 = 911T same rear rotor until the rear vented discs came out.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Montreal914
post Nov 6 2025, 08:13 AM
Post #7


Senior Member
***

Group: Members
Posts: 1,955
Joined: 8-August 10
From: Claremont, CA
Member No.: 12,023
Region Association: Southern California



Here you go. (IMG:style_emoticons/default/smile.gif)

914 Rear rotor:
solid
diameter: 282mm
thickness: 9.4 (or 9.5?)mm
caliper piston dia: 33mm

914-6 Rear rotor:
solid
diameter: 286mm
thickness: 10.4mm
caliper piston dia: 38mm

914-6 GT Rear rotor:
vented
diameter: 286mm
thickness: ?
caliper piston dia: 38mm (same caliper as 914-6 with a spacer)
No longer available but there are ways around
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
chmillman
post Nov 6 2025, 09:49 AM
Post #8


Member
**

Group: Members
Posts: 202
Joined: 15-June 24
From: Switzerland
Member No.: 28,183
Region Association: Europe



QUOTE(Montreal914 @ Nov 6 2025, 03:13 PM) *

Here you go. (IMG:style_emoticons/default/smile.gif)

914 Rear rotor:
solid
diameter: 282mm
thickness: 9.4 (or 9.5?)mm
caliper piston dia: 33mm

914-6 Rear rotor:
solid
diameter: 286mm
thickness: 10.4mm
caliper piston dia: 38mm

914-6 GT Rear rotor:
vented
diameter: 286mm
thickness: ?
caliper piston dia: 38mm (same caliper as 914-6 with a spacer)
No longer available but there are ways around


OK, great info, thanks much! So it looks like /4 calipers manage to accomodate the extra 1mm thickness of the /6 rotors - unless the pads were shaved in my case - but the extra 4mm in diameter is just a tad too much. Too bad. Options are change the calipers or remove the rotors and turn them down. Unfortunately my toolmaker's lathe is too small for me to be able turn the rotors myself.
User is online!Profile CardPM
Go to the top of the page
+Quote Post

Reply to this topicStart new topic
3 User(s) are reading this topic (3 Guests and 0 Anonymous Users)
0 Members:

 



- Lo-Fi Version Time is now: 6th November 2025 - 04:19 PM
...