# Axially mounted Porsche Cayenne 4 piston calipers...



## junkeravant (Jul 12, 2012)

Well I've decided to go with 2 bracket suppliers for my project. One is Apikol and the other is Creation Motorsport. Right now I'm getting a pair of Cayenne 4 piston axially mounted calipers ready to mount on my A4/B5 Avant. Using S8 rotors but I'm getting flak over it. Some people say the calipers are too big while others say they are exactly the same size as the calipers I have on my A4 now. I went out and checked and sure enough they were right. Apikol says my Calipers are bigger them my A4's. Creation says no. Both make adapter brackets for my need. Hmmm?:banghead::what:


----------



## Chickenman35 (Jul 28, 2006)

junkeravant said:


> Well I've decided to go with 2 bracket suppliers for my project. One is Apikol and the other is Creation Motorsport. Right now I'm getting a pair of Cayenne 4 piston axially mounted calipers ready to mount on my A4/B5 Avant. Using S8 rotors but I'm getting flak over it. Some people say the calipers are too big while others say they are exactly the same size as the calipers I have on my A4 now. I went out and checked and sure enough they were right. Apikol says my Calipers are bigger them my A4's. Creation says no. Both make adapter brackets for my need. Hmmm?:banghead::what:


Do you have the actual piston diameters on the Cayenne calipers that you will be using? 

Piston size is critical. Even Creation Motorsport has incorrect information on their website. They list Porsche Boxster REAR calipers ( by Part number ) as being suitable for the front of various Audi's. * THIS IS 100% WRONG!!! * 

There is a huge amount of mis-information out there on the Internet. Do a bit of searching and you'll find that a lot of that has been addressed on the Vortex, and very recently. Unfortunately Porsche part numbers can be confusing ( and again, there is mis-information on the Internet ), so it is best to physically measure caliper diameter before conversion. 

Please read the following thread *thoroughly* regarding piston sizing and and make sure that you understand how to calculate Piston area and it's affect on " Clamping force ". It should help you with your project.

http://forums.vwvortex.com/showthread.php?7003812-Porsche-caliper-issue

BTW. It's a bit hard to follow what you are saying. Can you be more specific?


> I went out and checked and sure enough they were right.


 Who was right? What were they referring to? Physical size of calipers or piston diameter? What calipers are on your car now? Stock? :beer:


----------



## junkeravant (Jul 12, 2012)

*You are absolutely right about piston size...*

It would do no good to put in a 4 piston caliper that has a piston area smaller that the ones I have on my OEM A4 caliper now. I'm getting a bad feeling that the Cayenne 4 piston caliper is either a wee bit smaller or equal to the A4's piston area. What bothers me is why Porsche would use such a small area front 4 piston caliper on such a heavy vehicle like the Cayenne? I think that is why they went with a 6 piston later in the build. No?


----------



## Chickenman35 (Jul 28, 2006)

junkeravant said:


> It would do no good to put in a 4 piston caliper that has a piston area smaller that the ones I have on my OEM A4 caliper now. I'm getting a bad feeling that the Cayenne 4 piston caliper is either a wee bit smaller or equal to the A4's piston area. What bothers me is why Porsche would use such a small area front 4 piston caliper on such a heavy vehicle like the Cayenne? I think that is why they went with a 6 piston later in the build. No?


Until you measure the piston diameter or otherwise confirm the piston size, you are just guessing and making assumptions.I looked around a bit last night but couldn't quickly find the info on the Cayenne calipers quickly. I simply don't have time to go researching Porsche calipers every few days for people. That's your job.. 

Measure the piston diameter and you will have your answer in 5 minutes. We don't have the calipers in front of us. You do. Too many times I've seen on this forum ( and others ) people who think they have bought front calipers and then later found that they have rears. Come back with the measurements and we can go from there.


----------



## junkeravant (Jul 12, 2012)

*Piston sizes were small...*

25mm & 22mm. I also checked the Porsche PN# 20 7673.04 8A They are apparently rear calipers. My goof for not asking the seller more specific questions.:banghead:


----------



## Chickenman35 (Jul 28, 2006)

Oh dear. Yes those are rear calipers and the piston diameter is really small. Those won't work at all. Sorry to hear that, but better you find out now than after you've done the complete conversion and bought brackets, new pads etc. :beer:


----------

