Which caliper is this??

[marcesq]

Ok, need help once again. PET program says this is the right front caliper. Part no 986 351 422.



Green arrow is pointing to the smaller of the two pistons.



Another view.


My common sense is telling me that the bleeders should be up, and the larger piston should be first in direction of travel. Another words, I think this is the left front caliper, not the right.

Don't want to install these puppies upside down

Thanks as always for the help.

[Bill Verburg]

They are Boxster calipers 36/40 leading/trailing, bleed valve goes up, 421 is supposed to be left, 422 is supposed to be right. Boxsters use trailing mount so swap the bleeds and feed to change from trailing to leading mount
You will need 4 M12x1.5x72 high strength bolts to mount them(assuming that the axial to radial adapters are drilled to standard Boxster spec)

Use Carrera rear M rears w/ matching rotors for best bias.

[marcesq]

Thanks Bill. Now I can get to work.

Hope you and your family had a great Thanksgiving.

PS: I'm the birdy in Richard's ear.

[marcesq]

Originally posted by Bill Verburg
Use Carrera rear M rears w/ matching rotors for best bias.

That is the plan.

Thanks again.

Marc

[quint22cp]

I am resurrecting this thread as I have a dilemma over my recently acquired 996 ebay calipers.

"marcesq" 's 422 caliper indicates that the smaller piston is on the right.

I have 996.352.422 calipers with the smaller piston on the left.

Now I am really confused, which is the leading piston, small or large ?

I have popped out and measured the pistons and my 422's and the small ones are at opposite ends to "marcesq" 's

Can someone clear this up and give me a definitive answer for small or large leading piston ?

[quint22cp]

.

[Bill Verburg]

No matter what car, when mounted, the small piston always leads(sees a given spot on the rotor first when moving forward), the bleed is always on top.

There are 2 possible mounting configurations

the 996 and Boxster fronts and the 930 rear use what is called a trailing mount configuration. the caliper is mounted behind the rotor.

All 911 use leading mount where the caliper is mounted ahead of the rotor.

On this 996 the front brakes are trailing and the rear are leading

[quint22cp]

Thanks for posting the picture, this helps a bunch.

regards


Pete