Alternative to Hydroboost or I-boost braking.

white-rhino

Older than dirt
Joined
May 19, 2020
Member Number
154
Messages
999
Loc
Michigan but not in Detroit
The one thing I have hated on my buggy from day 1 is lack of good brakes. The OB used a traditional dual Wilwood balance bar, dual 1" bore master cylinder braking system with one ton calipers in the front (Chevy KP 60) and 1/2 ton Chevy calipers on the rear 14 bolt. The day after I brought it home I ordered 3/4" masters and eventually ended up with 7/8" front and 3/4" rear MC's. It would always drive through the brakes and I got pretty adept at kicking the trans into neutral all the time to not fight the brakes. I was able to hold position on a steep incline but it was always scary and if I had to back out of something steep, I risked rolling too far back before I could stop it.

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I looked at both Hydroboost and I-boost and packaging was just too tight. JohnnyJ and I came up with an idea for a remote I-booster but we agreed it was going to be claptrap. Then I stumbled on an electric brake booster sold by Jegs. Although expensive, I didn't feel I had any decent options so I ordered one up.

Directions were pretty straightforward.
With further research, it's actually made by a company in SoCal called American Brake and Steering. (ABS) Clever acronym.
Early on I had some pressure issues and they were very helpful on the phone.


JohnnyJ had a busted knuckle pedal assembly that he wasn't using so I picked it up to see if I could make it work. I had to bore out the bracket for the larger MC and it fit right in.

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The pedal was too long and too straight with a > 6:1 pedal ratio. In a perfect world, 4:1 would probably be better but when it will work and it's free, don't complain.

I had to cut the pedal and bend it towards the driver seat. (just tacked up)

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Also added an adjustable stop for the brake light switch.

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So once I was comfortable with the pedal assembly, where to mount the pump unit? It's pretty small and my first idea was to mount it right behind the pedals. It would fit but would be hokey.

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I opted to mount it in the front of the passenger footwell. The slick thing about this unit is that it only has two lines to it, a gravity drain from MC and a pressure line to the MC. Wiring is a constant hot and ignition hot. It has it's own built in pressure sensor and relay.

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You will notice in this pic I have the return drain going through my inner console panel. Next time the panel comes out it will be slotted for easier access.
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Master barely fits but fits.

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I’m no expert plumber but since I only needed one new hard line it came out decent.

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Used JohnnyJ ’s flaring tool. Worked like a champ.

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So then it was time to final weld, paint and do a permanent install. I used to proud of my welds. Now I suck. :shaking:

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Once it was finalized, time to bleed and test. After this experience, I’ll say it is SUPER important to have a gauge for testing. Again JohnnyJ came through for me.

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Bleeding and testing was frustrating. My MAJOR mistake was not taking pressure readings with the OE Wilwood system. (Johnny couldn't find his gauge till I was back home) :flipoff2::lmao:

So with no baseline, I had to go from scratch. Johns testing on his system was around 500-550 psi manual and his I-booster bumped him up to 1250 at his axle. So that was my bogey. My first go around was the same as John's @ 500-525 manual.

I should note, this ABS system is pretty cool. When energizes, it stores enough energy to get 6-8 assisted pedal strokes before it bleeds off. When it bleeds off, it reverts to manual brakes. It's definitely noticeable when this transition happens.

But I was super bummed that when the system was energized, I was only getting 750 psi at the axle. What a disappointment! My first intuition was that my plastic brake lines were swelling causing the problem.
For reference, the published output at the pump is 3000 psi and 1600 - 2000 at the MC. Plastic brake lines are rated 1800 - 2000 depending on who you ask so this is why I thought I had a problem.

I called ABS and they gave me some suggestions to check but had no input on plastic brake lines. So I decided to start back at step one. I installed the gauge directly on the pump. The gauge only goes up to 2000 psi and the pump maxed it out. Good! Then I put the gauge on the rear output of the MC and only got 1100 psi. WTF! Nowhere close to the 1600+ as advertised. So last night I went to bed pretty dejected.

I did the 2:00am wide awake thing and got to wondering if I was getting full stroke at the MC. The heim was adjusted out as far as possible. So this morning I did a bench test and found I was short stroking the MC by about .300". I welded a nut onto the heim to lengthen it and WOOHOO! I now have 1900 psi at the output of the MC!

Next was a good bleed of the brakes and I ended up with 1100+ psi at the rear axle and 900+ psi at the front axle. Since John's baseline was 1250, I felt pretty good. My belief now is that the 1 ton front caliper volume is greater than the 1/2 ton rear calipers and the MC doesn't have quite enough stroke to max them out at full pressure.

Now for the test drive. With the OE, I could drive through the brakes, would only come to a rolling stop and could not lock up the brakes. Cutting brakes would occasionally lock up but rare and only on loose dirt. Now when hitting the brakes (on gravel) I can lock up the rears, the nose dives and it will put you against the harness. Full lock up? No. Cutting brake locks up on hard gravel. On pavement, I cannot drive through 2:1 low range and with effort can force it to drive through 4:1 low range, but the frame is twisted and it's a struggle.

So, I think I am happy. I leave for out of state in 12 days so I'm excited to check it out. And here's the good part, EVERYTHING is interchangeable so if this system doesn't work as hoped, I can have the Wilwood back into it in a couple hours.

Update to come in two weeks.
 
JohnnyJ had a busted knuckle pedal assembly that he wasn't using so I picked it up to see if I could make it work. I had to bore out the bracket for the larger MC and it fit right in.

The pedal was too long and too straight with a > 6:1 pedal ratio. In a perfect world, 4:1 would probably be better but when it will work and it's free, don't complain.

Free? I thought we agreed to negotiate the price after it worked.

New the pedal is $111, but since I used it in my buggy it now has provenance and coupled with you cutting it up into pieces and bolting it in your rig it just adds to the value. Pay up!

edit: ...and let's not forget the rental fees on my rare Amazonian pressure gauge with vintage fittings.
 
Free? I thought we agreed to negotiate the price after it worked.

New the pedal is $111, but since I used it in my buggy it now has provenance and coupled with you cutting it up into pieces and bolting it in your rig it just adds to the value. Pay up!

edit: ...and let's not forget the rental fees on my rare Amazonian pressure gauge with vintage fittings.
“After” it worked we need to discuss the extensive amount of cleaning, sanding, modification and painting it required to turn it from scrap to barely usable. :shaking:

I’ll admit the gauge is worth a beer. :beer:
 
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Nice.

I'm curious what car this pump system comes from.

Also, do you know the MC bore?
 

They even have a mini MC version




This HAS to come from an OEM application. I'm really wondering where from.
 
This HAS to come from an OEM application. I'm really wondering where from.
X2. This would really solve a lot of issues for people. Just need to get beyond the $1500 price tag.
 
I did the 2:00am wide awake thing and got to wondering if I was getting full stroke at the MC. The heim was adjusted out as far as possible. So this morning I did a bench test and found I was short stroking the MC by about .300". I welded a nut onto the heim to lengthen it and WOOHOO! I now have 1900 psi at the output of the MC!
What's the travel numbers you're getting at the MC?
 
Nice.

I'm curious what car this pump system comes from.

Also, do you know the MC bore?
No idea on OEM application but they seem to have several versions.

MC bore is published @ 1-3/16"
Just need to get beyond the $1500 price tag.
I struggled with that too. I believe both hydroboost and Iboost can be done cheaper but sometimes it comes down to limited options. For me, my wife has been afraid to drive it because she can barely reach the pedals and can't apply enough manual pressure. NOTE she drives it VERY rarely but I've always had that mentality that "if I break a leg, you need to be able to get us out of here". It's also been convenient on trail rides where if I'm up at the front of the group helping to pull cable etc that she can move the rig forward, and sometimes it's not flat ground.

When I consider how much is already invested, another $2k isn't much considering how important it is.
What's the travel numbers you're getting at the MC?
Honestly would have to measure and I can't access it right now. (I have to pull my hood and cowl to access it) Oddly they don't publish a MC stroke. My measurements were only based on how close I was to fully compressed.
 
Hydraulic, Air, Vacuum, Mechanical~
 
I think I have found the pump.

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Now for the MC...
Application?


I'm very happy to go away from the TEVES 2 system. Self contained and has ABS and worked great for decades, I'm certain. Expensive pain in the ass if it ever needs rebuilt.

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Hydroboost off an engine driven pump or vacuum boost, way too many options out there that are workable, even if it needs some creativity to pedal mounts
 
No idea on OEM application but they seem to have several versions.

MC bore is published @ 1-3/16"

I struggled with that too. I believe both hydroboost and Iboost can be done cheaper but sometimes it comes down to limited options. For me, my wife has been afraid to drive it because she can barely reach the pedals and can't apply enough manual pressure. NOTE she drives it VERY rarely but I've always had that mentality that "if I break a leg, you need to be able to get us out of here". It's also been convenient on trail rides where if I'm up at the front of the group helping to pull cable etc that she can move the rig forward, and sometimes it's not flat ground.

When I consider how much is already invested, another $2k isn't much considering how important it is.

Honestly would have to measure and I can't access it right now. (I have to pull my hood and cowl to access it) Oddly they don't publish a MC stroke. My measurements were only based on how close I was to fully compressed.
Pretty sweet the difference being just due to the travel, that's a breath of relief!
 
Sorry, yes, Prius. Also got the diagram, it's simple to wire.

Problem is finding the MC.
 
Makes me wonder too. Since it’s all polished up (obviously not OEM), I wonder if they are making their own.
Not all of them:


Did you look at how your system is wired?
I'm assuming something like this :

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What fuse value do you have? 20amp?
 
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do you got an instruction manual or possible quick sketch of the plumbing of the master cylinder?

curious on how the boosted pressure relieves itself when you let off the brakes
 
do you got an instruction manual or possible quick sketch of the plumbing of the master cylinder?

curious on how the boosted pressure relieves itself when you let off the brakes
There is a return back to the resi.

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where was that buried? i was looking around, but gave up after clicking on a few systems
Their website sucks.

The MC with integral resi has a return that goes back to the resi directly so it doesn't "appear" to be there.
 
gotcha, thats the piece i was missing

im really intrigued buy this system. seems to resolved the main gripe of packaging with the iboost system with all the benifits
 
gotcha, thats the piece i was missing

im really intrigued buy this system. seems to resolved the main gripe of packaging with the iboost system with all the benifits
I know the UFO 4500 runs that system.
 
Not all of them:


Did you look at how your system is wired?
I'm assuming something like this :

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What fuse value do you have? 20amp?
Yes that schematic looks right. It’s a simple 10 ga wire to battery and 16 or 14 to ignition. Not sure on fuse size, would have to look but I think it was more.
My system doesn’t have a resi.
Looking forward to real world testing next week.

And yes their web site sucks. Phone help was very pleasant but not very technical.
 
an ABS system?
Yes

Yes that schematic looks right. It’s a simple 10 ga wire to battery and 16 or 14 to ignition. Not sure on fuse size, would have to look but I think it was more.
My system doesn’t have a resi.
Looking forward to real world testing next week.

And yes their web site sucks. Phone help was very pleasant but not very technical.
I'd appreciate if you'd take a look at the fuse value. Whenever you have time.
Thanks

Phone help rarely is good in aftermarket companies.
 

They even have a mini MC version




This HAS to come from an OEM application. I'm really wondering where from.
I tried to do a bunch of research in the ibooster thread, I'd love for someone with more current automotive knowledge to help out.
 
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