• Forum membership has its advantages....

hydro boost or other power boost for brakes?

osborne

Well-Known Member
Can someone please tell me how to add some sort of power assist to race car brakes. I have cnc hanging pedals with separate m/c's for front and rear. I can not get enough power even with proper m/c size, 6 piston fronts and 4 piston rears. I do not have room for a typical booster like on most trucks. Is there a way to add a remote hydro, electric, vac. or other booster? Some pics or web sites would be great. Thank you.
 

PaulW

Well-Known Member
Electric has higher pressure than vac and that pressure depends on the pump you use. Hydroboost is probably the most commonly used. HB uses pressure and fluid from a power steering pump and it is very common to have two pumps, one for steering and one for brakes. One pump is good enough for an non race rig, but it compromises steering and braking at the same time.
I have experience on all three for my non race rigs. If I was going to build racer I would contact "ABS Power brakes" and discuss with them to provide a EB setup with line pressures higher than their standard setup and dual accumulators.Their kits include a custom master.
With my rigs I found HB (single pump) and stock EB have similar performance. My HB came from "Hydrotech" and is basically a chevy setup with all new parts and uses a Chevy master.
Easiest to package is EB because it will fit anywhere and is not connected to the motor..
 

osborne

Well-Known Member
I guess my main question is how can I hook up some sort of booster to the m/c's I have? I am unfamiliar with how it works. I have limited room near them and would need some sort of remote system.
 

y2kbaja

Well-Known Member
We ran a Toyota booster behind the seat operated by a clutch slave. It was a different brake pedal feel but the truck would stop on a dime.
 

PaulW

Well-Known Member
The EB master has a return line as the fluid is circulated. You have to do some engineering to use a non compatible master. Hard to imagine a non compatible master will work.
Talk to the companies that sell the EB stuff. Then get the correct master or masters. Why keep stuff that wont work or requires mods?
Maybe you need to revisit your brake design?
 

EOR1488

Well-Known Member
I Think Josh 8 just did a hydroboost set up. Was looking for it in the build section but cant seem to find it.
 

green787

Well-Known Member
Can someone please tell me how to add some sort of power assist to race car brakes. I have cnc hanging pedals with separate m/c's for front and rear. I can not get enough power even with proper m/c size, 6 piston fronts and 4 piston rears. I do not have room for a typical booster like on most trucks. Is there a way to add a remote hydro, electric, vac. or other booster? Some pics or web sites would be great. Thank you.
Most medium duty trucks have a rear brake booster that runs off engine vacuum that you could use.

Brake Booster.jpeg
 

07FJRog

Well-Known Member
Change the pads on your brakes, qtm stoptech makes pads for many calipers, also hawk performance. I have wilwood 6 piston all the way around and my 3300lb truggy doesnt stop very well either, so a pad change is in order soon
 

Josh 8

Well-Known Member
IMG_1430.JPG
IMG_1431.JPG
IMG_1432.JPG


Here is what I did. I use to use the Cnc buggy pedal assembly but it just wasn't strong enough. So I built a rocker assembly that fits in the same mount the Cnc unit used. I did not want to get under the dash of this thing with grinder and welder. Any way, the rocker confers the pedal push to pull and a cable wraps around the right side of the cab to behind the right seat. Here the secound rocker turns pull force back into push at the vacuum chamber.

The vacuum chamber and master are stock 94 f150 parts. Plus there's a inline bias valve in the rear break line.

The system has plenty of power. I have 4 puck calipers all around and it will flat stop the truck. But and it's a big BUT. It runs out of vacuum fast. I have a big cam in the engine and doesn't pull any vacuum to help the electric pump. I either have to add a secound vac pump in parallel or go to an electric booster. I have been shock testing and it simply runs out of vacuum to fast if your pumping the brakes. No buano.

If I do the electric boaster I think I can keep all the hard parts in place and just swap the vacuum chamber for the electric booster.

If you have any more questions just ask.
 

osborne

Well-Known Member
I put the softest willwood pads in. It helped but not enough.

Change the pads on your brakes, qtm stoptech makes pads for many calipers, also hawk performance. I have wilwood 6 piston all the way around and my 3300lb truggy doesnt stop very well either, so a pad change is in order soon
 

osborne

Well-Known Member
Josh 8- I get what you did there, nice. But I don't quite get how the brake peddle is actuating the cable. I assume you were saying running the cable straight off the peddle wasnt enough so you went to a cam set up for more "leverage"? That set up may work, I could just not figure out how to activate the m/c's back there. The cable is genius.
 

Josh 8

Well-Known Member
IMG_1155.JPG
This is on the 8 truck in the pic.The cable runs parallel to the fire wall. The reason for this is because there is no room to run it forward through the firewall. There's shocks and tower mounts there. The ratio is still one to one. The reason for the right angel cantilever turn is to get the cable to do a U turn and run parallel to the firewall. If you look in the secound picture you can see the rating tag for the cable in the upper right of the pic. In the same pic you can see the heim above the fulcrum bolt in the left of the pic. In the third pic your looking up at the cantilever link that converts foot push to cable pull. The bolt to left in the third pic has the heim on the other end attaching to the cable.

To fix the lack of vacuum issue I am adding a secound vac pump in parallel to double the suck. Hopefully it works.

Does that make sense?

So here is the real question. What's it cost? I use to make my living in my fabrication shop. I now do it for my pleasure but if I was to do this for a customer it would be at least 32 hours at $90 an hour plus $1000 in parts. What's that? $4k. Is it worth it? For me, yes. My time and labor is cheaper than cash. If it was hydro boost it would probably be close to $3k more after the parts and pump was mounted. Maybe more.
 
Last edited:

Zambo

Well-Known Member
I didn't have room on the front of the firewall to mount a brake booster because that is where my shocks are, so I extended the pushrod that connects the brake pedal to the booster and mounted the booster way up front by the radiator.
 

Slippery P

Well-Known Member
Hydroboost, is the only way to go, most units are pretty easily packaged and readily available.
 

JEFFRPM

Non Sugar Coated
Why do you need a booster in the first place? If the master cylinder to caliper ratio is correct along with the motion ratio of the peddle it should stop easily without much effort at all. Get a carol smith book read up on braking math and rid yourself of all that complicated/heavy I failed spelling
 
Top