Following on from my thread in the general section
http://www.e30zone.net/modules.php?name ... c&t=153062
this has now turned into a technical question:
How can I tell if the calipers on the front of my 325 have been changed or if they are the originals meant for ventilated discs ?
How to identify calipers....
Moderator: martauto
The vented disc is 22mm, the solid is only 12mm. The vented/ unvented parts of the brakes aren't interchangeable. For mounting the vented discs (which the 325 originally was equipped with) you need new calipers.
OK. Thanks.
So to do the job properly I will need calipers discs and pads... or the cheap option is to stick with solid discs and just replace discs and pads like for like.
Is there really any advantage for me "up grading" to the ventilated set up ? I've not really had any problems with the solid set up that the car has had since I've had it.
Just out of interest, what makes it impossible to use the vented discs with my existing calipers ? Do they not open up enough to let the disc in due to the extra width or is it an alignment problem ?
So to do the job properly I will need calipers discs and pads... or the cheap option is to stick with solid discs and just replace discs and pads like for like.
Is there really any advantage for me "up grading" to the ventilated set up ? I've not really had any problems with the solid set up that the car has had since I've had it.
Just out of interest, what makes it impossible to use the vented discs with my existing calipers ? Do they not open up enough to let the disc in due to the extra width or is it an alignment problem ?
These are sensations as hard to forget as they are to ignore.....
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Brianmoooore
- E30 Zone Team Member
- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
Vented disc is 10mm wider than the solid, so the gap between the parts of the caliper that hold the pads needs to be 10mm further apart. Pads, pistons, and everything else is the same.
Thanks for the info Brian.
It seems that all I need to do is measure the gap in the calipers then, obviously having pushed the piston back in as far as it will go and allowing for the width of brand new pads.
If I've got it right, the distance between the face of the piston and the face of the sliding hanger when fully open needs to be a minimum of 17mm (pad) + 22mm (disc) + 17mm (pad) = 56mm. If it isn't in excess of this I need new calipers.
It seems that all I need to do is measure the gap in the calipers then, obviously having pushed the piston back in as far as it will go and allowing for the width of brand new pads.
If I've got it right, the distance between the face of the piston and the face of the sliding hanger when fully open needs to be a minimum of 17mm (pad) + 22mm (disc) + 17mm (pad) = 56mm. If it isn't in excess of this I need new calipers.
These are sensations as hard to forget as they are to ignore.....