My sense is there is a normal degree of braking action throughout the pedal stroke. The stroke is too long under hard braking conditions for my liking. I should add that I think the level of pedal pressure required is appropriate. I would not want more brake boost. Unfortunately, what I have just written is qualitative. I apologize that I don't have quantifiable data.
So the real question is why does the pedal stroke increase when pressing the pedal harder? What is the source of the compliance? Is the caliper flexing? It does have a bridge, but who knows? The Neuspeed kit includes SS brake lines, so I guess not there. Flexure of the master cylinder or its mounting to the firewall? The pedal mechanism mounting flexing? The pads compressing? Questions abound!
My understanding is a pressure valve mentioned in another thread can alleviate a dead spot by holding the pad closer to the rotor. That would reduce pedal travel that occurs before there is any braking effect.
I feel you pain on that. I think there's something wrong and it can be fixed cause there's plenty of people with bbks that don't complain about this. Mine is basically doing the same thing. The only thing that fixed it was going back to stock rear brakes. It was borderline undriveable for me though.The 40168 code didn't work. I couldn't get the VCDS ABS bleed procedure to work.
I have performed 6 pressure bleeds, 4 two-person bleeds, each followed by a road test that activates ABS, all in accordance with the erWin manual. (The erWin manual does not include an ABS bleed procedure.) I'm still intermittently seeing a few air bubbles during bleeding from all of the calipers. The pedal feels better, engagement is high, and the brakes work well on the street, but I can still (too easily IMHO) force the pedal to the floorboard.
I performed a master cylinder pressure bleed down test, adapting the procedure described in the erWin manual (looking at data acquired by VCDS instead of attaching a pressure gauge to a caliper). In three tests, the first test exhibited excessive pressure loss. The other two did not. I think the first test got into the smaller bore portion of the MC (reached with longer pedal travel) while the other two did not. I'm going to conduct the test a couple of more times to get better confidence in the results.
Still, I've reached the end of my patience and have scheduled an appointment with my favorite VW/Audi indie shop. In talking with them, they said that they have seen similar problems on client cars with high piston count BBKs.
I haven't yet looked into it at all cause I haven't been driving the car lately. I'm gonna take the rear apart soon and order new ss rear brake lines to see if that changes anything.Yeah, I read about your issue. Very strange indeed! Have you had a chance to sort it out?
Sounds like the Neuspeed calipers have the same shortcoming as the Macan kit, mismatched piston diameters for your master cylinder sizing. Non-PP GTI has a smaller MC right? PP/R/S3 might be somewhat better. Do you know the piston diameters?
I performed the bleed at 30 psi. I didn’t bleed both front calipers at the same time. That would require four hoses and bottles!If you have air trapped in your system the manual says to use a pressure bleeder at 30 PSI and bleed both front calipers at the same time. I have used this method and it seems to work well.
Well two bottles and two hoses, you don't have to bleed both sides of the caliper at the same time. I believe the idea is to push fluid through all channels of the MC and ABS unit at once to force out the air. I usually start with the inside caliper pistons and finish with the outside, then the rears one at a time. I use a half gallon of cheap DOT 4, once you are sure you have all the air out then replace with the expensive high temp stuff.I performed the bleed at 30 psi. I didn’t bleed both front calipers at the same time. That would require four hoses and bottles!
I didn’t bleed both fronts at the same time, so no, issue remains unresolved.Does that mean you solved the issue you were having? With the pedal to the floor?
Give that man a prize!My prediction. They find nothing and tell you it's normal.