AP 6 Piston Front Brake Kit

Updated 2/6/04


When these systems were first introduced, I believe they were priced from around $3500 to $4000.  However, at one particular Stillen open house, they had advertised the system for $1995.  I hemmed and hawed for awhile, before making the decision to buy at that price.  So when I finally made that decision, imagine my disappointment when I was told that there had been a mistake and that the sales sign was a mistake.  I was disappointed, but at the same time, I thought that was $1995 that I would save.  So no biggie for me.  However, a little later in the day, Frank S, the VP of sales, came up to me and said they would honor the price for me as sort of a favor for the bad experience that I had had with their rear strut tower brace.  Frank also asked if I were willing to write a review for the system.  So thinking about it for a second, I took them up on the offer.  What a mistake that would turn out to be.

So with my new super duper brake system we went back to my friend's house and installed the system on my Z.  Installation was a breeze except for the stainless line that connects the caliper to the brake line.  This line was easily 1/2" too short.  After much wrestling with the line, we finally got it to fit.  However, it was way too tight and I was definitely afraid of it breaking due to the extra tension on the line.  However, I had no choice, as we were doing this installation in Southern California and I needed to get back home to Northern California.  My friend, who works closely with Stillen fed back the issue on the short line so that it would be fixed in the future.  I replaced the line later with a slightly longer one.

Other than that, the system worked fine, except for some pretty loud squealing - problem #2.  I figured that after further bedding, the noise would go away.  After driving more, the noise was still not going away.  I called Stillen and talked to someone in the brake department who said it was a race system and to expect some noise.  Ok, so please tell me which pad you were using, so I can try another one.  Well sorry I am told,, but we can't tell you what pad is used.  Ok, no problem again, as I figured that I would take the pad off and see if I can learn anything more.

Oh oh.  Problem number #3.  I could not get the caliper bridge bolts off of the calipers in order to take the pads out.  The only way to get the pads out was to remove the whole caliper.  What a pain in the rear that was.  By the way, the pad was made by Pagid as the Pagid name was on the backing plate of the pad.  After talking to another Stillen retailer, I was informed that the bridge bolt were made of stainless steel and that the helicoil is most likely made of stainless as well.  Stainless on stainless hardware has a history of seizing.  I had experienced that first hand in my own job.  Oh well, I guess I was going to have to continue to take the entire calipers off in order to change pads.

Well, I called back Stillen and talked to the manager of the brake department, who said that they were working with AP on an anti-vibration shim to try and quiet the systems down.  He said since I was one of the first people with the system, that he would send me some shims to try out.  Well guess what, to this day, the shims never came

Well the noise was still there and it was loud.  I mean it was so loud that as you came to a stop at an intersection, people were all turning to look where the loud noise was coming from.  This was not acceptable, so I started talking to some real experts from the auto industry who suggested using an anti squeal compound or a different pad.  I tried the anti squeal compound first and although it helped, the noise was still way too loud.  Finally I tried a different pad and had success.  Not only were the pads quiet, but they were a lot cleaner than the original Pagid pads.  These were Hawk HPS pads if you are interested.  The only hassle during these experiments was having to take the entire caliper off again in order to change the pads.  I really didn't like doing this, as it is really inconvenient, especially when you're going to the track often, and doing a lot of pad changes. 

So after a few months of constant caliper removal, I broke down and was determined to get these bolts off.  Before I did that, I tried to buy some extra bolts from Stillen.  However, it became such a hassle just trying to find someone that even knew what these bolts were,  that I contacted AP in England.  They provided me the part number, which I used to order from another AP distributor in the USA.  Thank god this was a part that did not have to be exclusively purchased through Stillen.  So with extra bolts in hand, I removed the calipers and tried to remove the bolts.  Unfortunately, the only way that these were coming off, was by machining them off.  Luckily, I have a friend who has a machine shop where he carefully machined out the bolts.  I replaced the helicoils and put the whole system back together with a small dab of anti-seize compound on the bolt threads to ensure no more seized bolts.  This solution has worked great for me and everyone else that I recommended this to . 

The only issue was that I still owed a review of the system to Stillen.  I was suspecting that they were expecting a favorable review of the system, although nothing was never implied or expressed.  There were so many issues that I had to fix on my own and there seemed to be no improvements to the kit based on the feedback I provided.  The reason that I suspected this, was because others who had purchased the kits after me, had contacted me and told me of similar problems to the ones that I had encountered.  So in the end I sent a check to Stillen to refund them the difference between the regular price and the special sale price that I received, and informed them that I would not write a review.  Until today, I had not written a review, but if people had asked my input, I was openly honest with them.  I guess in hindsight, I should have not made assumptions on the expectations of the review that I was suppose to write.  I should have just written it and let the chips fall where they may.  

Some final thoughts on this system.  As it is advertised, this system is designed to work under the highest heat loading conditions, which I consider to be track conditions.  I can confidently say that it does, but I also have to say that most serious open track people have learned the hard way to not use crossed-drilled rotors.  Unfortunately, this option was not available either as part of the original kit or as replacement parts from Stillen.  I have since been able to source such rotors at much better prices, so there are solutions out there.  By the way, I did eventually crack the cross-drilled rotors at the track, but that was expected.

With my modifications, this system works absolutely great under track conditions.  I have since had the opportunity to install a kit that was sold from AP in England for use on the Z32 and Skyline.  This particular AP kit is sold everywhere in the world except in the US.  In the US, Stillen sells their own  custom version of the kit.  This AP kit went on a friend's car.  I can said that I prefer the Stillen AP system better than the direct AP system.  The rotors are thicker and there are no modifications of the front spindle required.  The powder coat or painted finish on the Stillen calipers is also much nicer.