ep3(uk) FN2 front calipers..same as ek9 calipers?
- Thread starter fitzer
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hmm would have never thought they were smaller than ek9 pistons..
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It's actually ideal, the smaller piston offsets the larger disc, meaning no overall gain in 'power', which means no need to upgrade the rears to keep the brake bias the same.
All properly engineered BBKs work on this principal. Those massive Bremo and AP calipers people fit on their track and race cars actually have less overall piston area than the stock calipers!
All properly engineered BBKs work on this principal. Those massive Bremo and AP calipers people fit on their track and race cars actually have less overall piston area than the stock calipers!
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That makes sense, but they have less piston area so less force being applied? Therefor making the gain in disc obsolete in this case? So an advantage would be disc temp due to less force being used by the calipers?
I'm guessing all of this so need confirmation
but then theyre stopping 200hp while the ek9 brakes are stopping 185hp, i know it doesnt make that much of a difference but it is a difference..
anybody have any tried and tested imput on this? haha
yeah i get ya.. but it would have to have some sort of slight advantage the bigger disks over the ek9 282?
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I'm wanting to compare the two different brakes on the same car.
So why would the ep3 brakes be an upgrade on an ek9.
Why is the bigger disc an advantage if the force applied by the ep3 calipers is less? I'm assuming it's less although it's just a smaller piston?
Complete novice on brakes so trying to learn
So why would the ep3 brakes be an upgrade on an ek9.
Why is the bigger disc an advantage if the force applied by the ep3 calipers is less? I'm assuming it's less although it's just a smaller piston?
Complete novice on brakes so trying to learn
im the same man haha, im assuming it would be a bit better stopping because its set up from factory to stop a bigger engine?
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There are only two aspects to brakes that you need to really consider, heat and bias.
You rarely want to **** with the bias, if you do you usually want to move it reward if you want improvements. Adding front bias reduces your overall brake power, even if the ratio of brake power to pedal force increases, because brake force is limited by tyre traction. If your car weighs 2000lbs and your tyres have a friction coefficient of 1 then you have 2000lbf of brake force you can use at the most, which will be distributed between the four tyres according to the dynamic weight distribution. If under braking your weight distribution is 80% on the front (fairly standard for a FWD) then you want 80% of the braking done up front, and 20% at the rear. In this case you use 100% of the total available brake force.
But now, consider what happens when you make the front brakes more powerful. Say now, they do 90% of the braking. This is good right, because the fronts do the majority of the work, it makes sense to make them more powerful!
Well, actually no. Instead, what happens is the front tyres still lock up at the same point, because the tyre grip hasn't increased. Only this time, you've not pushed as hard on the pedal. Instead of increasing the brake force by 10%, all you've done is make the same brake force, with 10% less input. That might not seem significant, it might even seem desirable, but consider that with 10% less pedal force, you've got less fluid pressure, the same pressure which also feeds the rears, so the rears are now doing less work. So what right? They don't do much anyway?!
Well, it's not much, but it was 20%, which is now 10%. The fronts are doing the same as before so overall, out use of the available grip has fallen to 90%. That means instead of 2000lbf of brake force, we've now only got 1800lbf. In terms of 'units G' we dropped from braking at 1G to 0.9G.
So straight away, adding front brake force has lost us performance. That's not the end of it though! With a 200lbf reduction in the deployed brake force, we've reduced our acceleration, which reduces load transfer. Reduced forwards load transfer means less load on the front tyres, which means we lock up earlier, which means less rear force again! This runs in a feedback loop,and usually means that a percentage change in front bias, results in a larger percentage reduction in total brake performance. That's to say, you might add 10% more powerful front brakes, and end up losing 20% performance! Probably not what you were aiming for, I'm guessing...
The idea of bigger discs is straightforward, more mass takes longer to heat up, and more surface area cools down quicker. Who wouldn't want that?! Well, I for one wouldn't, if it came bundled with increased front bias!
The idea of bigger brakes is almost always better thermal capacity, NOT more brake force, and this is why bigger discs are almost always designed in conjunction with caliper smaller pistons, the reduced clamp force offsets the increased force lever, keeping the overall torque roughly the same. End result, same bias (maybe even slightly reward) and improved heat dispersion. Perfect.
You rarely want to **** with the bias, if you do you usually want to move it reward if you want improvements. Adding front bias reduces your overall brake power, even if the ratio of brake power to pedal force increases, because brake force is limited by tyre traction. If your car weighs 2000lbs and your tyres have a friction coefficient of 1 then you have 2000lbf of brake force you can use at the most, which will be distributed between the four tyres according to the dynamic weight distribution. If under braking your weight distribution is 80% on the front (fairly standard for a FWD) then you want 80% of the braking done up front, and 20% at the rear. In this case you use 100% of the total available brake force.
But now, consider what happens when you make the front brakes more powerful. Say now, they do 90% of the braking. This is good right, because the fronts do the majority of the work, it makes sense to make them more powerful!
Well, actually no. Instead, what happens is the front tyres still lock up at the same point, because the tyre grip hasn't increased. Only this time, you've not pushed as hard on the pedal. Instead of increasing the brake force by 10%, all you've done is make the same brake force, with 10% less input. That might not seem significant, it might even seem desirable, but consider that with 10% less pedal force, you've got less fluid pressure, the same pressure which also feeds the rears, so the rears are now doing less work. So what right? They don't do much anyway?!
Well, it's not much, but it was 20%, which is now 10%. The fronts are doing the same as before so overall, out use of the available grip has fallen to 90%. That means instead of 2000lbf of brake force, we've now only got 1800lbf. In terms of 'units G' we dropped from braking at 1G to 0.9G.
So straight away, adding front brake force has lost us performance. That's not the end of it though! With a 200lbf reduction in the deployed brake force, we've reduced our acceleration, which reduces load transfer. Reduced forwards load transfer means less load on the front tyres, which means we lock up earlier, which means less rear force again! This runs in a feedback loop,and usually means that a percentage change in front bias, results in a larger percentage reduction in total brake performance. That's to say, you might add 10% more powerful front brakes, and end up losing 20% performance! Probably not what you were aiming for, I'm guessing...
The idea of bigger discs is straightforward, more mass takes longer to heat up, and more surface area cools down quicker. Who wouldn't want that?! Well, I for one wouldn't, if it came bundled with increased front bias!
The idea of bigger brakes is almost always better thermal capacity, NOT more brake force, and this is why bigger discs are almost always designed in conjunction with caliper smaller pistons, the reduced clamp force offsets the increased force lever, keeping the overall torque roughly the same. End result, same bias (maybe even slightly reward) and improved heat dispersion. Perfect.
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Don't forget you can use my Honda brake setup Web app for free here: http://blackartdynamics.com/BrakeBasic/BrakeIndexHonda.php
Luger
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So as I understand it here.....I dont need to touch the OEM rear ek9 calipers and discs as bias will not suffer due to the smaller EP3 front caliper piston size and I can keep the OEM ek9 rear caliper and disk size? Correct?
Do the EP3 front calipers and 300mm discs fit under OEM ek9 wheels or do I need spacers?
Thanks
Do the EP3 front calipers and 300mm discs fit under OEM ek9 wheels or do I need spacers?
Thanks