Boxster Calipers Front V s Rear

matty74 · matty74's Garage

This is probably stupid question, but because I don't know I have to ask.

I have a set of 4 boxster calipers to go on my 911 they look very similar to one another how can I tell which are front and which are rear.

whats the defining difference?

A Quiet Boom · A Quiet Boom's Garage

Piston size, the fronts are larger. At least thats how my 996 brakes are which I'm putting on my 911.

obrut · 10-30-2006, 08:34 PM

matt

also - at least for the front calipers - don't forget to reverse the lines to swap the Left caliper for the Right and vice versa. The boxster front calipers mount on the rear of the wheel not front of the wheel (like a 911) and they have leading and trailing cylinders of different sizes.

can't recall if you need to do the same for the rear or not.

lateapex911 · 10-30-2006, 08:45 PM

Does that impact the location of the bleeders???? That could be problematic.

obrut · 10-30-2006, 09:14 PM

yes, you have to swap the lines/bleeders etc fron one caliper to the other in order to have the bleeders at the top of the caliper when mounted.

matty74 · matty74's Garage

Yeah I thought so the adapters for the rear position the calipers at the back at 3O'Clock

matty74 · matty74's Garage

I checked the part numbers as it turns out I have 2 pairs of front calipers

both pairs have 986.351.421.03 and 986.351.422.03 as part numbers.

which are fronts.

Rears are 986.351.423.03 and 986.351.424.03 so I need to find someone who has pair of rears they want to swap. I had these freighted al the way from the US.

hmd · 11-02-2006, 01:15 AM

Matty,

You may find the boxster all round would be too rear bias so you may be better off selling the extra pair and just get some Carrera rear calipers.

matty74 · matty74's Garage

Yeah that is my thinking too

matty74 · matty74's Garage

I can put on a brake bias value on the rear line that should sort it?

matty74 · matty74's Garage

A local porsche wrecker in australia has told me that the boxster calipers I have a rears.

now the part numbers are XXX.XXX.421.XX and 422 respectivley on both pairs of calipers, rears are supposed to be 423 & 424 but he tells me they are rears that the part number don't matter cause its the same casting.

Now I'm totally confused as to what I have if some one can help me identify what i have got