NA8 rear brake pads (does it even matter what brand I use?)

Wheels, Suspension, Brakes & Tyres questions and answers

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GTR4N
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NA8 rear brake pads (does it even matter what brand I use?)

Postby GTR4N » Tue Jul 29, 2014 5:18 pm

So planning on doing a brake pad service on a NA8 which I'll be picking up.

I'm planning to go with QFM HPX pads ($79) on the front along with a machining of the front disc

Now with the rear, what I want to know is, how much brake bias is there being sent to the rear calipers when I step on bake pedal? Because I'm lead to believe that most of the braking occurs in front brakes.

Which leads to my question, does it matter what rear pads I use? so long as they are general purpose low dust and low noise?

I was just planning on going with some "N Brake ECR Brake Pads" which are offered by QFM as the general purpose pads rated for temp range of 0-400 degrees Celsius... and probably cost $40...

Is there any reason for using the same $79 pads on the rear?
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Re: NA8 rear brake pads (does it even matter what brand I us

Postby GTR4N » Tue Jul 29, 2014 5:23 pm

and its not like the NA8 has EBD like in other more modern vehicles...
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Re: NA8 rear brake pads (does it even matter what brand I us

Postby plohl » Tue Jul 29, 2014 5:53 pm

If you're planning on doing any hard braking (track days etc) then I would stick with the higher temp pads. If anything you want more bite in the rear.

I don't think it would make a major difference driving around the street. You'll lock up the fronts anyway.
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Re: NA8 rear brake pads (does it even matter what brand I us

Postby GTR4N » Tue Jul 29, 2014 5:59 pm

Yeah only looking at doing spirited street driving, I can understand that having good pads front and rear when doing a track day will increase the brake bite on all 4 rotors
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Re: NA8 rear brake pads (does it even matter what brand I us

Postby NitroDann » Tue Jul 29, 2014 6:13 pm

The more grip and front braking you have the less you use the rears.

EBD hardly has anything to do with it.

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Re: NA8 rear brake pads (does it even matter what brand I us

Postby sailaholic » Tue Jul 29, 2014 6:31 pm

If your doing spirited street driving then fit the same front and rear or work out a pad with more bite for the rear to get more use if the rear brake.

You will need to look at coefficient of friction for various pads across there operating range to work that out not just the max operating temp.

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Re: NA8 rear brake pads (does it even matter what brand I us

Postby greenltd » Wed Jul 30, 2014 6:20 am

Why not just fit the same all round? If the good pads are only $79, how much will you save fitting cheaper pads on the rear? Not worth mucking around.

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Re: NA8 rear brake pads (does it even matter what brand I us

Postby Magpie » Wed Jul 30, 2014 7:50 am

The question of bias
1990-1993 the rear is 40% of the front pressure (995 f and 597 r)
1994-1997 the rear is 30% of the front pressure (850 f and 597 r)

Both share the same knee point of 427. Knee point is where the proportioning valve kicks in below this point the brake pressure to the front and rear is the same.
The question of bias
1990-1993 the rear is 40% of the front pressure (995 f and 597 r)
1994-1997 the rear is 30% of the front pressure (850 f and 597 r)

Both share the same knee point of 427. Knee point is where the proportioning valve kicks in below this point the brake pressure to the front and rear is the same.

sailaholic is correct that by using a pad with more bite on the rear will give some more braking effort. You could look at Winmax W1's on the front and W3's on the rear or A1RM's on the rear. However increased rear bias could make the car unstable under hard braking.

Personally I would go the manual proportioning valve so that you can tailor the bias. At the moment I'm running Winmax W5's on the front and W3's on the rear, so effectively I have more bite on the front but W5's are not the best pad for street use due to needing a min of 100 deg c to be effective.

The reason that the front needs more bite than the rear is due to weight transfer. When under hard braking the front has more weight and hence needs more braking power. Under heavy braking the rear is lighter hence does not need as much bias. Perfect brake bias is obtained when the front-to-rear balance of the brake system exactly matches the front-to-rear weight balance of the vehicle. For a track car this is easy as brakes are on hard or off, however for a road car getting the perfect balance is impossible due to the way the brakes are used, sometimes ridden, slammed or applied gently. Therefore brake bias for road use is a compromise.

sailaholic is correct that by using a pad with more bite on the rear will give some more braking effort. You could look at Winmax W1's on the front and W3's on the rear or A1RM's on the rear. However increased rear bias could make the car unstable under hard braking.

Personally I would go the manual proportioning valve so that you can tailor the bias. At the moment I'm running Winmax W5's on the front and W3's on the rear, so effectivley I have more bite on the front but W5's are not the best pad for street use due to needing a min of 100 deg c to be effective.

The reason that the front needs more bite than the rear is due to weight transfer. When under hard braking the front has more weight and hence needs more braking power. Under heavy braking the rear is lighter hence does not need as much bias. Perfect brake bias is obtained when the front-to-rear balance of the brake system exactly matches the front-to-rear weight balance of the vehicle. For a track car this is easy however for a road car getting the perfect balance is impossible due to the way the brakes are used, sometimes ridden, slammed or applied gentley. Therfore brake bias for road use is a comprimise.

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Re: NA8 rear brake pads (does it even matter what brand I us

Postby GTR4N » Wed Jul 30, 2014 9:17 am

Wow very informative post guys! Thanks heaps! Ok will take all suggestions on board. After posting I also watched a video which made a point of if your rear brakes aren't doing anything this leads to front brakes having to work even harder to compensate and eventually lead to front brake fade quicker... So having same or better rear brakes is a way to take the pressure off the fronts
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Re: NA8 rear brake pads (does it even matter what brand I us

Postby GTR4N » Wed Jul 30, 2014 9:20 am

Btw this is a much nicer forum, have previously come from ozhonda which was over crowed by dick heads and keyboard warriors, this is a refreshing change
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Re: NA8 rear brake pads (does it even matter what brand I us

Postby Magpie » Wed Jul 30, 2014 9:55 am

Brake fade can be caused by a few things:.
1. Water in the brake fluid boiling causing a spongy feel. Brake fluid is hygroscopic, therefore it is important to change it often;
2. Brake lines expanding therefore reducing brake pressure. The expansion could be because of age of the lines or as per point 1 water boiling in the brake lines;
3. Pads too hot, this will more than likley have a firm pedal but no slowing down. Generally there will be smoke from the pads.

If you want to play with brake setup you really want the rears to NOT lock before the fronts. Due to weight transfer under heavy braking and all the weight on the front the last thing you would want is no grip in the rear. This is generally why there is a less agressive pad in the rears for most road cars.

I'm glad you are finding this forum a nice place to be.

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Re: NA8 rear brake pads (does it even matter what brand I us

Postby project.r.racing » Wed Jul 30, 2014 9:59 am

greenltd wrote:Why not just fit the same all round? If the good pads are only $79, how much will you save fitting cheaper pads on the rear? Not worth mucking around.
^this^

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Re: NA8 rear brake pads (does it even matter what brand I us

Postby GTR4N » Wed Jul 30, 2014 4:16 pm

greenltd wrote:Why not just fit the same all round? If the good pads are only $79, how much will you save fitting cheaper pads on the rear? Not worth mucking around.


well my initial thoughts were if $79 for front pads and $49 for cheaper rear pads (provided there were no extreme down sides but it seems there are some to consider)

= $30 left for an oil change...
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Re: NA8 rear brake pads (does it even matter what brand I us

Postby chrons_rotary » Wed Jul 30, 2014 11:35 pm

I say buy the $79 pads front and rear, and hold off doing the oil change till you get another $30, unless your oil is black.
As you can see, most of the guys here recommend at least having the same pads front and rear.
These guys know their stuff so the info given can be relied upon.

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Re: NA8 rear brake pads (does it even matter what brand I us

Postby GTR4N » Wed Jul 30, 2014 11:43 pm

Yeah I agree after reading all the comments that running the same pads front and rear is the way to go, don't mind me I'm just being a tight ass, every $ adds up in the end so was just trying to weigh up my options before.
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