Jump to content
SAU Community

Recommended Posts

Hello, 

I have changed lately brake booster (second hand ) and install new braking pump. Bleed the system 5 times. My ABS is disconnected

Every time i press the brake pedal i hear one hiss sound, is that nornal or not? ( its not like a constant air leaking, just one short hiss when press )

When i press the pedal and start the engine i can feel the brake pedal is falling a little bit down. This is the only test i have done so far.

The braking system is not working too well lately, i need to use a lot of force to stop the front wheels at higher speeds around 100km/h.

I heard the braking system is not too good in this cars. What do you recommend to upgrade to improve the braking system? My leg is hurting sometimes from hard braking and i want to track day this car sometimes.

 

 

 

 

11 hours ago, GTSBoy said:

Not true. They're pretty good.

I would suggest that your 2nd hand booster is no good. Get it rebuilt.

I have comparision how the braking works in different cars, I daily drive M5 E60 and Peugeot 407 and i am not using force on the pedal almost at all for hard and quick stopping from low speeds. After going back to my Skyline r33 when i use the same amount of force nothing happens.  I need to push pedal really hard to get the same results.  This is why i say the stock brakes are pretty bad in Skylines, or brake booster is too small and not doing the job.

Edited by Tomak

Problem is that i dont know if the brake booster works efficiently. What can i expect from the second hand 20 year old booster?

I did a test yesterday and disconnected brake booster and try to drive my car and the car had no braking power at all. I mean you could berely brake without booster it was so dangerous to drive, the handbrake was much  better without the booster. I guess the booster is working pretty good because the difference is huge.  Question is it working efficiently.

I wish i could purchase the new brake booster. Do you know if this part is available somewhere in Australia, Japan or maybe USA?

The part number i need is 23U11. Its the brake booster from GTS R33 since i have this one after the conversion swap RHD to LHD

It can be also refabricated if you know the source where i can get one.

 

 

Edited by Tomak

I have never driven a Nissan where you could not engage the ABS without excessive force on the pedal. When people say brakes are not good enough they usually mean that with many rapid applications they lose stopping power. If you have to stand on the brakes to pull the car up normally then there is a fault. Sounds like you were just unlucky with your replacement booster.

Has this problem existed ever since you disabled ABS? Sure all the brake lines are connected properly?

BTW almost any booster should do.

e.g. https://www.trademe.co.nz/motors/car-parts-accessories/nissan/brakes/listing-2262431068.htm?rsqid=84e0244abd7f4ea2aea053cf26cb1d59-001

 

12 hours ago, Tomak said:

It can be also refabricated if you know the source where i can get one.

Take it** to a brake workshop. Give it to them with a small handful of money (like, <$200 worth) and wait a couple of days. Presto, rebuildo.

** The booster.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Yeah, that's fine**. But the numbers you came up with are just wrong. Try it for yourself. Put in any voltage from the possible range and see what result you get. You get nonsense. ** When I say "fine", I mean, it's still shit. The very simple linear formula (slope & intercept) is shit for a sensor with a non-linear response. This is the curve, from your data above. Look at the CURVE! It's only really linear between about 30 and 90 °C. And if you used only that range to define a curve, it would be great. But you would go more and more wrong as you went to higher temps. And that is why the slope & intercept found when you use 50 and 150 as the end points is so bad halfway between those points. The real curve is a long way below the linear curve which just zips straight between the end points, like this one. You could probably use the same slope and a lower intercept, to move that straight line down, and spread the error out. But you would 5-10°C off in a lot of places. You'd need to say what temperature range you really wanted to be most right - say, 100 to 130, and plop the line closest to teh real curve in that region, which would make it quite wrong down at the lower temperatures. Let me just say that HPTuners are not being realistic in only allowing for a simple linear curve. 
    • I feel I should re-iterate. The above picture is the only option available in the software and the blurb from HP Tuners I quoted earlier is the only way to add data to it and that's the description they offer as to how to figure it out. The only fields available is the blank box after (Input/ ) and the box right before = Output. Those are the only numbers that can be entered.
    • No, your formula is arse backwards. Mine is totally different to yours, and is the one I said was bang on at 50 and 150. I'll put your data into Excel (actually it already is, chart it and fit a linear fit to it, aiming to make it evenly wrong across the whole span. But not now. Other things to do first.
    • God damnit. The only option I actually have in the software is the one that is screenshotted. I am glad that I at least got it right... for those two points. Would it actually change anything if I chose/used 80C and 120C as the two points instead? My brain wants to imagine the formula put into HPtuners would be the same equation, otherwise none of this makes sense to me, unless: 1) The formula you put into VCM Scanner/HPTuners is always linear 2) The two points/input pairs are only arbitrary to choose (as the documentation implies) IF the actual scaling of the sensor is linear. then 3) If the scaling is not linear, the two points you choose matter a great deal, because the formula will draw a line between those two points only.
    • Nah, that is hella wrong. If I do a simple linear between 150°C (0.407v) and 50°C (2.98v) I get the formula Temperature = -38.8651*voltage + 165.8181 It is perfectly correct at 50 and 150, but it is as much as 20° out in the region of 110°C, because the actual data is significantly non-linear there. It is no more than 4° out down at the lowest temperatures, but is is seriously shit almost everywhere. I cannot believe that the instruction is to do a 2 point linear fit. I would say the method I used previously would have to be better.
×
×
  • Create New...