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S14_Kouki
03-27-2010, 04:23 PM
Hello everyone just got a few simple questions for you. To fill you in on what im doing. Im planning on making a hydraulic e-brake using a Wilwood master cylinder and my super awesome fab skills. Im pretty much going to make a powermax copy. Now my questions. Thank you for all your help :)

1. When running the lines off of the master cylinder. Where does the inlet go from the MC and where does the outlet go from the MC??? A diagram would be awesome.

2. What would be the best bore choice the .625, .700, or the .750??

3. The last but prob dumbest will I still have normal braking with the pedal??

http://i58.photobucket.com/albums/g269/pandadrifter/1219885032_2_FT3065_p1030544.jpg
http://i58.photobucket.com/albums/g269/pandadrifter/1219885032_2_FT3065_p1030543.jpg

Wilwood diagram

http://i58.photobucket.com/albums/g269/pandadrifter/wilwood.jpg

HPballer76
03-27-2010, 05:43 PM
the answer to 1 is on there site.. scroll down from where you got those pics and it shows you where the lines go.

2. in the pic you posted it has 0.625 stamped on the cylinder.

3. from the reviews i've read the pedal feel stays the same

NickyD0403
03-28-2010, 12:45 AM
5/8" bore for stock rear brakes
3/4" bore for big brakes

Pedal feel should not be affected at all, just bleed the brake system after you install the brake.

Line on top of the master cyl goes to the brake master cylinder
Line on the back of the master cyl goes to the rear brakes

I haven't done mine yet, but I will be doing it soon.

GSXRJJordan
03-28-2010, 12:55 AM
5/8" bore for stock rear brakes
3/4" bore for big brakes

Pedal feel should not be affected at all, just bleed the brake system after you install the brake.

Line on top of the master cyl goes to the brake master cylinder
Line on the back of the master cyl goes to the rear brakes

I haven't done mine yet, but I will be doing it soon.

Agreed 100%.

Your single rear brake line goes to hydro ebrake inlet, hydro ebrake out goes to your rear calipers.

3/4" bore is where it's at, I ran Z32 rears. Lockin' up 285's at freeway speeds if you crack it back pretty hard - coolest part is it's the quickest/easiest way to adjust angle at the track. Improved my driving a ton.

Pedal is not affected unless you're using both the foot brake and the hydro at the same time ~ this creates some weird stuff. Since pressure from the foot brake MC passes through the hand brake MC on it's way to the rear, it will put pressure on the hydro MC when you push the foot brake. If you're on the hand brake and step on the brake pedal, the hand brake will want to go back to it's resting position, and the foot brake will be extra stiff until the hand brake is at rest.

Make sure the metal you attach the hydro to is very strong (I boxed my mounting plate) ~ people that just bolt the MC to the tunnel end up tearing up the tunnel metal.

S14_Kouki
03-28-2010, 01:10 AM
Thank you guys alot for the info, I am now on the right track and understand everything :) GSXRJJorden thank you for the heads up on making a great mounting box.

dmaperformance
03-28-2010, 01:25 AM
Agreed 100%.

Your single rear brake line goes to hydro ebrake inlet, hydro ebrake out goes to your rear calipers.

3/4" bore is where it's at, I ran Z32 rears. Lockin' up 285's at freeway speeds if you crack it back pretty hard - coolest part is it's the quickest/easiest way to adjust angle at the track. Improved my driving a ton.

Pedal is not affected unless you're using both the foot brake and the hydro at the same time ~ this creates some weird stuff. Since pressure from the foot brake MC passes through the hand brake MC on it's way to the rear, it will put pressure on the hydro MC when you push the foot brake. If you're on the hand brake and step on the brake pedal, the hand brake will want to go back to it's resting position, and the foot brake will be extra stiff until the hand brake is at rest.

Make sure the metal you attach the hydro to is very strong (I boxed my mounting plate) ~ people that just bolt the MC to the tunnel end up tearing up the tunnel metal.


ok so i agree and disagree with Jordan, i have a few cars that i have this set up on, and if you running for fun its fine, but if you want to go pro or even just run comps for fun its no bueno, let me explain, first off you should not need any bigger the .625 master size, if you go bigger no matter what size brakes the handle gets hard to pull and the brakes become less efficient, wilwood specs that the .625 will be more then sufficient for brakes up to 6 piston on a single axle(meaning both sides aka front or back not both) secondly the reason i say its fine for fun driving but not competitive is the fact that sometimes in a race you need to use the ebrake and the front brakes, but with this set up it does not work at all, if you are on the ebrake and hit the pedal the pedal feels spongy and the handle locks up causing the rear to brake hard and most times a spin occurs, also after pressing the brake pedal if you grab the ebrake handle right after the handle feel is different, its very unpredictable. all my team race cars for this reason have been converted to 2 caliper hydo setups. other then that its great for track days or just fun stuff.

GSXRJJordan
03-28-2010, 01:53 AM
ok so i agree and disagree with Jordan, i have a few cars that i have this set up on, and if you running for fun its fine, but if you want to go pro or even just run comps for fun its no bueno, let me explain, first off you should not need any bigger the .625 master size, if you go bigger no matter what size brakes the handle gets hard to pull and the brakes become less efficient, wilwood specs that the .625 will be more then sufficient for brakes up to 6 piston on a single axle(meaning both sides aka front or back not both) secondly the reason i say its fine for fun driving but not competitive is the fact that sometimes in a race you need to use the ebrake and the front brakes, but with this set up it does not work at all, if you are on the ebrake and hit the pedal the pedal feels spongy and the handle locks up causing the rear to brake hard and most times a spin occurs, also after pressing the brake pedal if you grab the ebrake handle right after the handle feel is different, its very unpredictable. all my team race cars for this reason have been converted to 2 caliper hydo setups. other then that its great for track days or just fun stuff.

Paragraph breaks pwn you ~ the decent points you made will be lost on the impatient masses.

I'm curious what you mean by "competitive" and "race" events and "going pro", but that's neither here nor there. Neither I nor Google know who you are and you don't know who I am ~ regardless I used a tried/proven Formula D setup with the 3/4" bore and found that with Z32 rear calipers (similar rear piston/pad area to aftermarket rear setups I've seen) there was plenty of stroke in the hydro ebrake ~ I'd even considered stepping up MC size. I'm sure 5/8" works as well, but for an "upright"/long lever setup like I used (and the OP is making) there would be an undesirably long stroke IMO.

MC size doesn't change what happens when you slam the foot brake with the hand brake pulled ~ it's always going to want to close, and the pressure difference between your foot and your hand will determine where the balance goes. I made a habit of brushing the brakes right after a transition to 'set' the car before reapplying power and never had any problems setting the angle with the handbrake while touching the foot brakes, and I'm an average driver at best.

dmaperformance
03-28-2010, 03:12 AM
Paragraph breaks pwn you ~ the decent points you made will be lost on the impatient masses.

I'm curious what you mean by "competitive" and "race" events and "going pro", but that's neither here nor there. Neither I nor Google know who you are and you don't know who I am ~ regardless I used a tried/proven Formula D setup with the 3/4" bore and found that with Z32 rear calipers (similar rear piston/pad area to aftermarket rear setups I've seen) there was plenty of stroke in the hydro ebrake ~ I'd even considered stepping up MC size. I'm sure 5/8" works as well, but for an "upright"/long lever setup like I used (and the OP is making) there would be an undesirably long stroke IMO.

MC size doesn't change what happens when you slam the foot brake with the hand brake pulled ~ it's always going to want to close, and the pressure difference between your foot and your hand will determine where the balance goes. I made a habit of brushing the brakes right after a transition to 'set' the car before reapplying power and never had any problems setting the angle with the handbrake while touching the foot brakes, and I'm an average driver at best.

Well when i said being competitive, im talking about advancing your driving to a semi pro or pro level, i have currently 4 cars running the FD pro am circuit and 1 competing at the pro level, and for cars of this caliber, the advanced tracks and speeds, you need to sometimes be on the brakes quite a bit harder then "touching" them, sometimes you need to scrub speed alot faster.

no matter what size your MC when you press the pedal its going to bypass the handle. also yes the smaller MC will give you a slightly longer throw(which can be adjusted out if you have a handle stopping bolt, just adjust till the MC hits the beginning of its stroke) BUT, it makes the handle much softer on the effort it takes to pull, and during a long or all day event it helps with driver fatigue and also if you put a pressure gauge on the brake line you will see it performs exactly the same with locking the wheels, but puts much less force on the pads, meaning less heat, preventing brake fade during driving.

I understand that your setup works, but from my perspective i have to think of not only function but longevity, and yes i understand you couldnt find me on google, thats because im a small shop that does this as my passion not as my business, i simply sponsor and build cars for close friends and maintain my team vehicles, so i have no need to have a website or advertise myself or my business, and i hope you arent taking any of this as a attack on you, as you stated i dont know you, and i have nothing against you, im simply sharing the information i have come across with alot of testing, trial and error.

S14_Kouki
03-28-2010, 03:46 PM
From all the threads/write-ups/ companys that I have seen it looks to me like everyone runs the 3/4 bore size MC's

Car6on14
03-29-2010, 12:21 PM
hmm, had only seen Ksport hydro brake till now, how much is this pow max and how much cheaper is a ww master cyl? just trying to figure how much ull save, i kno the Ksport setup goes for around $175...

ILoveMyRHS13
03-29-2010, 12:22 PM
LOL

You aren't going to "save" money by getting the PBM hydro. It's definitely of much higher quality.

You can get a PBM hydro ebrake with lines for $300 + shipping. $220 without lines.

EDIT: I was supposed to be quoting "Car6on14" in this post. Sorry.

GSXRJJordan
03-29-2010, 03:49 PM
hmm, had only seen Ksport hydro brake till now, how much is this pow max and how much cheaper is a ww master cyl? just trying to figure how much ull save, i kno the Ksport setup goes for around $175...

The Ksport setup is nice because it's a "lay down" type instead of a "stand up" lever, and looks more like a factory ebrake. The Parts Shop Max ebrake is a high-quality unit for sure.

PoorMans180SX
03-29-2010, 06:27 PM
Rally cars run Hydro e-brakes inline with their rear brakes. No separate calipers.

DJPimpFlex
03-29-2010, 07:24 PM
I run my car with an inline set up with no problems over about 7 events. The brake bias at high speed while riding the ebrake and touching the foot brake (to adjust the front wheel speed) works rather well, just something to get used to. The feel is definitely different.

I don't think running an extra set of hydro calipers just for the ebrake is a worthwhile investment. The extra complexity and unsprung weight outweighs the advantages IMO.

Here's a pic of my set up
http://i2.photobucket.com/albums/y32/DJPimpFlex/New%20Car/photo3.jpg

Also, mine is bolted to the standard tranny tunnel and I haven't noticed any problems at all. Its at a different angle than most, but it feels very solid.