Guys and Gals

 

Just wanted to see what the general consensus was around brake pedal feel and progression in their zeds

 

To start, im still running stock calipers rebuilt with new pistons, seals, sliders etc, HEL lines, DBA 4000 discs and DS2500 pads all round. Im 99.9% sure my system is air free and im running DOT 5.1 fluid thats less than 12 months old. I do have big brake kit almost ready to go, but im sure this "issue" isnt caliper related.

 

Ok, so as much as im happy with the performance of the stock brakes (although ill freely admit they dont have the out right power that i now feel i need due to my substantial increase in power) in that they VERY rarely fade (even on track), however there are a couple of things that i think could be improved upon compared to new cars (not even sport car specific)

 

Firstly, pedal travel and initial bite of the brake. I have found when changing from the zed to either my work car or the misses company 5 series, newer car have that initial brake bite right at the top of the pedal movement (especially in the 5 series). No when i get on the brakes, the modulation is fine on the zed and comparible to new cars, but personally for me that higher up bite gives me a bit more confidence for late braking/emergency braking situations.

I have found however, with almost a slight tap of the pedal (certainly not a "pump") it brings the biting point right up to where I feel it should be. I have discussed this with John Dixon before, and his opinion is that it something to do with the design of the brake master cylinder. While i dont doubt him, im wondering if there are any other contributing factors..... maybe something with the vac assist that could be upgraded etc etc etc....... interested to know your thoughts on this one!

 

Secondly, ABS cut in.

I dont know if any of those who have tracked your car have found, but when leaning hard on the brakes (but very progressively) that you can feel the abs pulsate through the pedal, but the ABS isnt actually engaging/disengaging the brakes and you momentarily loose braking force? This is something ive experienced a few times on track, and it can be a bit eye opening to say the least! The only way i seem to be able to get around this is to very quickly (cadence style) disengage and re engage the brakes, and all is well again.

As I mentioned in a thread a long long time ago, when taking part in an accident reconstruction with the police (look up 300zx vs merc vito for the thread) that the actuation of the ABS is significantly slower than that of a modern car.

Do you think that this odd manner is something to do with either the ridiculously long routing the brake lines make too and from the ABS unit, how the ABS is designed to work, etc etc etc.

 

Oh and something else, have any of you found that when the ABS cut in, it kills the stereo?

 

Id like to know:

 

how many of you experience some of the things ive described above

Any further ideas around initial engagement of the brakes in relation to pedal movement, ideas on how to improve it?

Any other quirks you have found with your zeds braking system and if you managed to get around them

Have any of these quirks been resolved by changing to a Big Brake conversion?

 

etc etc etc

 

Cheers

 

Nick

I can honestly say I have never had any of the problems what so ever and the brakes are just as keen as is the peddle. As both of my 3 series.

 

I also only really felt the abs twice with late brakeing on the b roads.

 

Since I updated I never looked back. I think you might have something a miss?

 

Tyres and widths etc play a massive factor

Without reading through, I seem to remember complaints surrounding the abs unit and its affect on pedal feel.

I can honestly say I have never had any of the problems what so ever and the brakes are just as keen as is the peddle. As both of my 3 series.

 

I also only really felt the abs twice with late brakeing on the b roads.

 

Since I updated I never looked back. I think you might have something a miss?

 

Tyres and widths etc play a massive factor

 

Tis always a possibility, but I'm confident it's not at the caliper end. Would like to bottom it out before big brake conversion

 

Tyre wise I'm running Fk453's all round (255/35/18 front 295/30/18 rear)

 

Once of the reasons I brought it up was around the chat i had with JD. He brought it up as something he was looking at resolving on his v8 car. However, knowing alot of the 200 guys change to Z32 master cylinders, may be its down the vac assist side of things?

2 things, the calipers dont have anti knock back, which is why you get more bit on the second press. You can put none return valves in the lines to help with this.

 

The extra long brake lines at the rear make temperature management an issue more than anything else.

 

I've had ABS removed for some time, and the ksports front & rear combo are fantastic! I made them go soft after about 20mins on track but reckon that could have been fixed through different pads.

 

Current setup is a bit nuts, hopefully with the pedal box it will even out and give me the consistent, (extra) strong braking force that I'm after.

Do you know if the 200 guys use the zed booster, a 200 booster or nothing?

Don't know Tbh it's beyond me. Could you not have a leak in a vacuum pipe. Seems odd you have to pump the pedal for it to stiffen up. That sounds like air?

Didn't Nissan have two types of cylinders maybe it was a fault they sorted.

 

Tyres are the same width as mine but I have 19 and falkens are good so it's not them.

Edited July 3, 201312 yr by Car.Mad

With tyres and abs, wondering of the extra mechanical grip of being wider at the front almost overwhelms the abs?

Do you know if the 200 guys use the zed booster, a 200 booster or nothing?

 

That I don't know. Seem to recall that the z32 MC is a bigger capacity unit than the 200 one

There's a lot of talk about "Z brakes" and how bad they are - but when the cars were new, they were regarded as excellent. And I believe it was Yowser who put up some stats comparing a new ZX (obviously taken back in the day) against a modern car with regard to braking distances; and the ZX still came out better.

 

And I speak with a little experience here, because I have driven a "nearly new" 300zx - the Sultan of Brunei's car now owned by PhilP - I took it out myself when considering buying it. OK it is a 1991 car, but only had 11,000 miles at the time!! And I have to say, the brakes were amazing - superb feel and good initial, confidence inspiring, bite. That was compared to my previous daily drive SLK350 which was (IIRC) 3 years/30k miles old at the time - and that had very good brakes too!

 

I currently have newly built calipers on my blue ZX - although I have a bit of a brake issue at the moment, where one appears to be dragging slightly - but there is still good initial bite and when braking from (very) high speed I am confident of stopping straight and true. And that's compared again to my current daily driver, another SLK350 which is about to turn 4 years old, has 35k miles on the clock plus the full AMG sport upgrades.....

 

Richard:thumbup1:

Richard, I agree. A fully working stock setup is very good. I remember the first Zed I had the brakes were shocking because some nutter in Japan put race pads in that never came up to temp on the road. Some semi-metallic pads made a world of difference.

That's interesting to hear rich.

 

However, to keep on topic, it's more about pedal engagement and how the abs behaves when it kicks in rather than over all performance