Wrong AP Caliper?

[Graham Sewell]

I have just picked up my Seven after having the AP big front brakes fitted and found that the bridge pipe under the caliper is fouling the offside wheel. On closer inspection it looks as though the caliper has been modified from an nearside version as:

1. the bridge pipe should have a 'kink' at the wheel side of the caliper.

2. the part number stamped on the caliper is the same as the one on the nearside (7605 3S0 CATER)

3. the arrow next to this part number is pointing downwards when the direction of movement of the disk is upward.

 

As the caliper uses unequal size pistons, this would put the small piston on the trailing side of the caliper - what would be the effects of this?

 

Obviously I am taking the issue up with the company involved but would like to know more at a technical level regarding safety, etc....

 

Cheers,

 

Graham

 

Low tech luddite - xflow and proud!

[Chelspeed]

Running the leading / trailing piston the wrong way round will lead to rapid uneven wear in the pad on the upside down caliper. The small piston will push a little on the lightly loaded end of the pad and the big piston will push hard on the highly loaded end of the pad.

 

I had this on a passat road car, VW changed the pad spec to a multi compound pad, hard on the leading edge, soft on the trailing edge. My dealer fitted them upside down and within a very few weeks the pad was like a slice of pie, gone at one end and full thickness at the other. A bit disconcerting.

 

I would think you're OK in the short term on the road to keep driving but I wouldn't compete like this and I'd keep a close eye on the pad. If deliberate then this is very shoddy work, sue the company and name and shame on the list.