I was talking to a mate of mine the other day who runs a G reg non ABS Z - and he doest seem to get the crap brake fade at high speed that im getting. Frankly sometimes it seems as though my ABS is just rediculous and im not going to stop in time for the roundabout ahead. Is this a common problem with ABS models ? If so - whats the best way of sorting that abs out ?

 

I have got EBC Pads, and Rotora Braided lines -so my brakes at low speed are great - but on the motorway they are awful - any views/ideas ? :confused:

bigger disc's

yes and n0 mate - brakes are shite (to be honest) but not brake fade - brake fade suggests new pads -

 

Regards,

 

alex

Isn't most 'proper' fade the fluid boiling? Needs replacing every two years.

 

If the ABS cuts in too much that's not right but not really 'fade'.

 

Pads always seem ok until they wear out in my (limited, motorbike based) experience.

The ABS is crap with bigger callipars. Not too sure if the standard Z pedal feel is down to it or not yet.

Going to remove mine when the V8's going in, so might do a write up then.

Isn't most 'proper' fade the fluid boiling? Needs replacing every two years.

 

If the ABS cuts in too much that's not right but not really 'fade'.

 

Pads always seem ok until they wear out in my (limited, motorbike based) experience.

Yep I agree.

 

ABS will not cause "brake fade at high speed". That's just to do with crap brakes (cause = old fluid, not using DOT5.1, old pads, u/s discs, not bled, old hoses etc etc).

 

As with most Zed issues, the fix is to solve the problem not paper over the cracks. (eg if you have worn discs, fix that, don't fit race pads; if you have flimp and loppy brake hoses, fix them (pref with Goodrich or similar but even OEM is better than nothing) rather than waste wonga on a caliper / disc upgrade).

 

ABS will operate your brakes better than you can (i.e. for maximum stoppage with maximum control / steering) in 99.99999% of the time unless your name is M Schumacher. Or V Rossi.

 

Some links http://aus300zx.neuralmotion.com.au/tech/abs/abs.htm

http://www.ttzd.com/tech/linestech.html

Thanks very much for your help chaps - i havent changed the fluid since ive had the car (2 years) so i will do that with some DOT5.1 and see if this makes the difference. The pads/discs/lines/callipers are all in tip top shape - so hopefully this should sort it

 

Thanks again - much appreciated

Sounds good.

 

I understand you're better with DoT 4 than 5 as some DoT 5s are silicone based and won't mix with ther fluids and cause other problems.

 

I good DoT 4 (maybe one labelled 'racing') would be what I'd go for.

What type of V8 are you putting in? Are you changing the gearbox etc too?

 

 

The ABS is crap with bigger callipars. Not too sure if the standard Z pedal feel is down to it or not yet.

Going to remove mine when the V8's going in, so might do a write up then.

I would check and make sure that your caliper pistons are not seizing. Make sure theey flow back and forth with ease. This is the biggest cause of brakes problems on Z's. I should know, I suffered for 3 years with it. Better to replace/upgrade the calipers if they are sticking, than to repair.

 

I found DOT 5.1 to be very good but I would recommend a full flush, not just a top up.

Sounds good.

 

I understand you're better with DoT 4 than 5 as some DoT 5s are silicone based and won't mix with ther fluids and cause other problems.

 

I good DoT 4 (maybe one labelled 'racing') would be what I'd go for.

 

Yep again. If you sling DOT4 into google you will find a lot of sites which say a) don't mix glycol-based DOT4 (or 3) with silicone DOT5.1 and, which I hadn't realised, that silicone DOT5.1 can feel spongier than DOT4.

 

I guess the benefits are it isn't hygroscopic (i.e. lasts longer) and doesn't strip paint - both of which are good things - but according to these sites doesn't give quite the same performance as 4

I'm no expert but I spoke to Silkolene / Fuchs (chief?) R&D chemist who is also a petrol head recently. It was him that said go for Dot 4 over Dot 5.

What type of V8 are you putting in? Are you changing the gearbox etc too?

 

Nissan VH45DE.

Should have some pics tonight, as spent today stripping it at Ztech. Will post them.

Brake fade has nothing to do with ABS.

 

Brake fade is caused by the pads over heating, on rare occations when the disc over heats. If your disc over heats it tends to cause it to have a blue sheen on it. This is called blueing and if they are blueish, they are wasted.

 

I really doubt what you are experiencing is brake fade I have had brake fade twice and both times is when I have been driving quite hard, ie, hard acceleration and hard braking. With brake fade you do not thing "Am I gonna make it for this roundabout" its "**** Im not going to make it" and you wont. Your brakes do not work at all with brake fade.

 

I think you just have air in the lines.

 

Are you sure your ABS is coming on. ABS does not activate all the time, only when it sensies 1 of the wheels locking, and then its only activates on the troublesome wheel.

It also makes a loud thudding and grinding sound when the ABS activates, as well as a vibratoin in the brake pedal. Are you getting that?

 

Which EBC pads do you have? Green stuff? If so green stuff are made for "Fast Road". Yeah right. Fast road for a 3/4 tonne Corsa or Saxo is not the same as fast road for a 1.5tonne car. EBC have actually said that the 300ZX needs Red Stuff V2 pads, which will make it not very good at slower speeds and better at higher speeds when the pads are hotter.

 

There may also be the problem of the calipers are sticking, causing them to rub hard against the disc all the time causing them to over heat.

 

I forgot there is another version of brake fade when the brake fluid in the lines boil. If this happens the brake fluid is fecked and worth less. Its recomemded that you change all of the brake fluid every 2-3 years, and use dot4. I have put Castrol Racing brake fluid in mine, which is a dot 4 and good to 900ºC or something.

 

You said you have braded brake lines. Did you install them yourself? You did bleed the brakes afterwards didnt you?

 

So conclusion is,

Change your pads to somthing which is more high speed. EBC Red Stuff if you are getting them.

Check your discs for blueing and/or cracks. If you find either, change your discs.

Bleed your brakes. Better yet change the whole lot. 2 litres is enough to make sure. Dot4, not DOT 5.1.

See if the calipers are seizing, check that the rubber seals on the pistons are in good condition, with no leaks or cracks.

I replaced all four discs.New seal kits etc. for the calipers.New pads. New s/s braided lines.New brake fluid. And then bled them about six times.And they are still shite.Will give them another few weeks of gently bedding them in and then have a rethink. Oh and new pistons in the master cylinder.

Antbody got any other ideas??

 

Mark

Shit in what way.?

 

You can have them good at low speeds or good at higher speeds. You cant have best of both worlds.

 

I find mine poor at around 30mph but drive 50-70 and slam the brake down and it stops very quickly.

Speaking for myself - I feel the brakes are very very poor at all speeds.

Iv`e got an A4 Tdi and the brakes are ten times better.I know it is a high compression diesel and you will get more servo assistance - but the nissan I feel should be alot better than this.

 

Mark

Shit in what way.?

 

You can have them good at low speeds or good at higher speeds. You cant have best of both worlds.

 

I find mine poor at around 30mph but drive 50-70 and slam the brake down and it stops very quickly.

 

 

Well you can have good brakes at all speeds.

I cant fault the A4`s - they are excellent at all speeds.

 

Mark

Well you can have good brakes at all speeds.

I cant fault the A4`s - they are excellent at all speeds.

 

Mark

 

 

Put your A4 brakes on it then ;)

 

You are compairing braking systems which are nearly a decade and half apart.

 

The 300ZX is very heavy

The braking system was designed in the 80s, the brake lines are now very old.

I bet a lot of cars still have the original calipers on.

Speaking for myself - I feel the brakes are very very poor at all speeds.

Iv`e got an A4 Tdi and the brakes are ten times better.I know it is a high compression diesel and you will get more servo assistance - but the nissan I feel should be alot better than this.

 

Mark

 

A lot of the complaints about the Zed brakes, is simply becuase they are faulty. Sticking Caliper Pistons seem to be pretty common.

 

300zx stock braking 60-0 distance : 116 ft ( or 129ft :confused: )

Audi A4 Tdi (2002) 60-0 distance : 130ft

 

 

(p.s - seems to be some conflicitng information on 300zx braking distances. I have multiple sources that either say 116ft or 129ft)

Put your A4 brakes on it then ;)

 

You are compairing braking systems which are nearly a decade and half apart.

 

The 300ZX is very heavy

The braking system was designed in the 80s, the brake lines are now very old.

I bet a lot of cars still have the original calipers on.

 

Not quite right.The previous A4`s brakes were designed before 1995.So more like 5 or 6 years difference.

But you are still missing the point.I also sometimes drive a 1988 golf and those brakes are better than the nissans.I still think this is the poorest system I`ve come across.Shame really as I love driving the car but the brakes are a big let down.

 

Mark

A lot of the complaints about the Zed brakes, is simply becuase they are faulty. Sticking Caliper Pistons seem to be pretty common.

 

300zx stock braking 60-0 distance : 116 ft ( or 129ft :confused: )

Audi A4 Tdi (2002) 60-0 distance : 130ft

 

 

(p.s - seems to be some conflicitng information on 300zx braking distances. I have multiple sources that either say 116ft or 129ft)

 

 

Well if those figures are correct all I can say is there is still something wrong with mine. Have replaced or overhauled most parts.

Did they ever work properly when the car came out of the factory???

 

Mark

Not quite right.The previous A4`s brakes were designed before 1995.So more like 5 or 6 years difference.

But you are still missing the point.I also sometimes drive a 1988 golf and those brakes are better than the nissans.I still think this is the poorest system I`ve come across.Shame really as I love driving the car but the brakes are a big let down.

 

Mark

 

I would say then that there is defiantly something wrong with your brakes.

 

Before buying mine, I test drove around 7-8 other examples. Half of which had shockingly Poor brakes.

 

The Zed brakes, when working correctly are actually pretty good, Not Brilliant though.

I would say then that there is defiantly something wrong with your brakes.

 

Before buying mine, I test drove around 7-8 other examples. Half of which had shockingly Poor brakes.

 

The Zed brakes, when working correctly are actually pretty good, Not Brilliant though.

 

Will have to start looking for other problems then.

Any ideas?

Havn`t tested the servo yet.

 

Mark

The master cylinder brace made a noticible difference to my pedal feel - good upgrade for the Zed I think.

...new seals in the brake master cylinder. Try this: Sit in the car with the engine running - car stationary. press the brake pedal hard and keep it pressed. Does it very slowly go down towards the floor? It's an MOT failure if it goes down under constant pressure. The testers tend to do this on older vehicles to check the state of the master cylinder seals. If they are worn then the hydraulic fluid leaks past them (it remains in the system) and you get reduced braking effort - as you describe. I bet your braking from high speed is prolonged and breaking at low speed is short duration.

 

Good luck

 

Jack