chrisw85

I've often wondered this. I could probably fab up a spacer to take the space of the booster; I've seen this done here before it was made of some 1-1/4" material (though I still dont get how'd youd make something to push the piston on the m/c). The spacer would be done mainly to cope with the flexing inherent in the booster. Would running around the street with the vacuum line disconnected be the same?

Any more info on this booster/no booster spacer thing? Search feature was temporarily down....

Of course, eventually, depending on what HC class I would build to, I'd like to mount a custon dual m/c setup from wilwood with a balance bar.

Honda318dx

Dave at SMSP is working on something for his imaginary H1 car .. I'll send him over here.

I ran with just the boster disconnected, it sucked! Dave told me not to, that it would suck, well, he was right..

MattD@Stoptech

You would need a much smaller M/C and much bigger pistons to make up for the lack of booster. Without the booster connected the pedal effort would be prohibitively high to run for any amount of time, not to mention the fact that you would be gaining absolutely nothing as the inherent flex would still be present.

SMSP

do do do do do do do do


When running just a disconnected booster, you have to also overcome the diaphram spring pressure in the booster so it's even harder to push the pedal down.

I first removed the booster on my 86 Civic back in 1991 while running AutoX in the E Prepared class to make room for twin carbs. I got the room and loved the feel. I ran the car that way until 2001 even for 4 years of road racing. It's sort of a built in ABS. I actually went up in size with the MC (1st gen Integra) so I graciously disagree with El Pollo Diablo. I found the set up much easier to modulate.

For my H1 car I decided to use an ITR MC but since it bolts at the 3 and 9 o'clock positions and the firewall holes are at 2, 5, 8 and 11, I needed an adapter plate. I used 1" thick aluminum since I needed to space out the MC from the firewall so I could actually get the top off. The flex you get is actually from the booster itself. Just have a friend push hard on the pedal and you watch the bosster body. The firewall is double walled and with the pedal frame bolted to it, it is actually fairly stiff.

Here's a pic of my set up

MattD@Stoptech

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SMSP &raquo;</TD></TR><TR><TD CLASS="quote"> I actually went up in size with the MC (1st gen Integra) so I graciously disagree with El Pollo Diablo. I found the set up much easier to modulate. </TD></TR></TABLE>

Consider yourself the lunatic fringe, a well designed dual-master system with custom pedal assembly requires usually around 80lbsf on the pedal to reach about 600psi of system pressure. You're operating at a much higher force requirement.

SMSP

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by El Pollo Diablo &raquo;</TD></TR><TR><TD CLASS="quote">

Consider yourself the lunatic fringe, a well designed dual-master system with custom pedal assembly requires usually around 80lbsf on the pedal to reach about 600psi of system pressure. You're operating at a much higher force requirement.

</TD></TR></TABLE>

I guess my legs are bigger/stronger, as I said it's easier to modulate (for me). You should try the brake pedal on a NASCAR set up.

chrisw85

SMSP, I'd like to know more details about that spacer.

I do have a 94 civic coupe ex ABS, would putting in a spacer like that provide any toruble? I suppose I could 'disable' the ABS circuit by the fuse.

I really would just like a better pedal feel. I do think i need to replace the m/c again (it appears to be replaced by the previous owner), while pushing the pedal down, i can feel a slight detent, almost as if the piston inside; one of the rubber seals is scraping. Braking is very good though, I have hawk HPS with valvoline fluid, but stock '94 rubber lines. Maybe the 'detent' i feel is some sort of side effect of how the pedal is actually mounted on a lever type system.

HapaHaole

The pedal ratios are COMPLETELY WRONG if you just remove the booster. Your pedal effort goes way way up without the booster. Even you working out at the gym 24/7 legs only wont help you get used to braking without the booster.

Okay maybe, just maybe you might be able to slow the car down a few mph, but you are pretty much writing your car off trying this-meaning youll have to use a wall to stop your car.

ryan12321

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HapaHaole &raquo;</TD></TR><TR><TD CLASS="quote">The pedal ratios are COMPLETELY WRONG if you just remove the booster. Your pedal effort goes way way up without the booster. Even you working out at the gym 24/7 legs only wont help you get used to braking without the booster.

Okay maybe, just maybe you might be able to slow the car down a few mph, but you are pretty much writing your car off trying this-meaning youll have to use a wall to stop your car.</TD></TR></TABLE>

I drove my car for a whole day at CMP last year without the booster hooked up. It was difficult compared to with it on, but it didn't stop me from slowing down from tripple digits.

HapaHaole

some people have higher tolerances for driving out of wack cars

hm.smitty

I have a '90 Integra that we race in Lemons and Chump Car. The ABS did not work so it was removed along with the proportioning valve. The lines were switched to front and rear (instead of diagonal) and an adjustable bias control was added to th rear circuit. Initially the booster leaked so bad that when you stepped on the brakes at an idle, it killed the engine! We disconnected it and plugged the vaccum line and raced that way for two years. Last year I changed the booster (to a 290), but there was little feedback or modulation control (too much boost), so I unhooked it again. I would like to run a booster. If I go to the 260 booster, or a 205 like my '90 CRX Si, will that lower the boost? Or in the alternative is their a way to limit the vaccum level and the boost that way? I appreciate your help with this, smitty

Robin6

You could also try to insert a vacuum relief valve and bleed off the boost to your liking.
Did this on my track car, I can dial in how much boost I get from the booster; adjustable booster.
My setup has the relief valve in the booster hose, between the check valve and booster itself.

Davidss

I have also run without the boosted hooked up and didn't hate it. Pedal effort is high but by no means impossible.

As the years have gone by new cars have gotten more and more brake boost. I am sure it must make it easier for a soccer mom to panic stop but I am not a fan for racing conditions.

117

Where did you find the vacuum relief valve? I've found a number of them, but curious which one you used since it obviously works.

Robin6

http://www.jegs.com/i/JEGS+Performan...23630/10002/-1
I used a "t" fitting to tap into the hose going to the booster.
Completely adjustable...dial in the desired feel, or leave it at full boost.
Just be sure to tap into the hose after the check valve which in my setup was built into the hose from honda. I cut out the check valve and relocated/spliced it closer to the intake manifold.

hm.smitty

I used a "t" fitting to tap into the hose going to the booster.
Completely adjustable...dial in the desired feel, or leave it at full boost.

If this is tee'd into the line, are you creating essentially a controlled leak? Does this cause any problems as far as leaning out the engine? Could I do this with a needle valve such as a speed control for an air tool? Thanks for the help, Smitty

Robin6

Nope, not leaning out the engine due to where the tee is placed in relation to the check valve and intake manifold.
The only drawback is there is less reserve booster vacuum once the engine is turn off.

Kozy.

Can't believe more people aren't running with this setup...

Robin6

The "Kozy Adjuster" is working well buddy!

FYI Kozy is the guy who invented this whole thing, I just put all the parts into play.

hm.smitty

Is it inserted in line (in series) or is it tee'd into the line (in parallel) ? Essentially does it limit the level of vacumn through the line or does it bleed off vacum down to a set level. Sorry to bother you with all the questions but I need to understand how it works before putting trusting it with my ability to stop. Smitty

Robin6

Hey hm.smitty. It is "T'ed" in. Between the check-valve and the booster.
I PMed you a diagram.

Start off closed and slowly adjust as you get use to the feel. Very simple.

hufflepuff

Most of these bleed valves use -AN (SAE) threads. Did you guys use some sort of adapter to go from SAE to a hose barb or something? Just curious about the plumbing. Thanks!