Is it possible to switch a vacuum brake booster to anything other than vacuum, mechanical or electric. I don’t know much about brake systems. I’m trying to eliminate as many vacuum lines as possible from under the hood.

 

As far as I know, there were Bullnose trucks that came with manual brakes. Finding one of these MCs would eliminate the vacuum booster from your truck. Make sure you get the proportioning valve too. You could also swap to hydroboost brakes. These were available on later trucks and the conversion is sometimes done on our trucks. This runs the brakes off of the power steering pump. Truthfully, if you're going simple. I suggest doing the manual conversion. The hydroboost doesn't use a vacuum line but you have an additional power steering hose.

https://www.ford-trucks.com/forums/1...al-brakes.html

https://www.ford-trucks.com/forums/8...-write-up.html

 

Note the pin the master rod hooks to is in a different place between power & manual brakes.
Dave. ----

 

You can do like I have planned. On my '82 if my 302 build doesnt produce enough vacuum I will be converting to a late 80s F-Superduty hydroboost brake system. You can pick up the hydroboost reman from rock auto fairly cheap compared to the aftermarket kits. You can also source a 7.3L powersteering pump reservior can which uses the same style pump as the older V belt trucks did. Youd also need the brake pedal as well as the pin is in a different location. You could use the vacuum brake pin location but you may end up with super touchy power brakes.

Beauty of doing it this way, it should all bolt in as the cabs are pretty much the same.

 

Going from vacuum assist to hydroboost you take away ONE vacuum line and add at least 2 hydraulic lines plus electrical wiring.

Removing the vacuum booster and going to non-boosted brakes would be the "cleanest" setup if your legs are up to it.

Good brakes are worth a little clutter.

 

The brakes are all good or they would not of been used, just 1 takes more leg to stop is all.

So do tell what electrical wiring needs to be done?
Is it for the brake lights?
If so the wiring is there but he may need to rework the switch mounting?
Other wise I dont see any wiring that needs to be done.
Dave ----

 

There shouldn't be any wiring for going to a hydroboost setup. There is nothing electrical in the system unless you are going with the late model brake reservoir with the fluid level sensor. But you arent obligated to run the late model master cylinder. I planned on running the OE '82 master cylinder on my application if I upgrade to hydroboost.

As far as the hydraulic lines goes, its nothing major. You take the pressure line from the power steering pump run it to the hydroboost pressure input. Then you run a line from the hydroboost pressure output to the steering gear box pressure input. Then the return line from the gear box to the power steering pump return. There is then a third line which runs from the hydroboost to the power steering pump reservoir. This line only has hydraulic fluid flowing through it in bursts as you apply the brake pedal. This is why you need to get a late model reservoir can to swap onto your power steering pump otherwise you'll have to tee into the return line between the gearbox and the power steering pump reservoir, but this can result in a whine due to aeriation of the hydraulic system.

Personally, I would avoid the hydroboost kits because they are thousands of dollars, and you can source all the pieces reman from the Autopart stores for a fraction of the cost if you know what to get.

 

Hydroboost usually has an electric backup.

OP wants to eliminate "as many vacuum lines" as possible. So yes, the hydraulic lines are not big deal but it's at least two or three hydraulic lines which as best I can tell, are just as ugly and cluttering as a vacuum line....

 

No, I dont think I have ever seen an hydroboost system even factory with an electric back up. Maybe the real new late model F-series trucks have them but I have not seen one with an electric back up system.

If he goes for a Hydroboost off a 1988 F-Super Duty with a 7.3 Diesel, Rock auto shows them for Cardone #527079, Prior #3700392, and Quality-Built #B5015. All reman with pedal rod without master cylinder, they all have your standard accumulator with no electrical hookup.

 

I picked up a hydroboost and brake pedal assembly from a 1992 F-450 for my 80 Bronco. I have an ‘87 F-series 1/2 ton master and it won’t fit the booster without a bit of mounting hole work. I haven’t tried the 80-86 but expect it to be the same issue and I want to upgrade to a switched, plastic reservoir version. The booster does mount to the firewall and appears to be right in line with the higher pin location of the hydroboost brake pedal.

I also picked up what is almost certainly a booster from a 6.0 power stroke diesel based on all the info I can find. It won’t mate to the firewall without a bit of mods and I think both pedal rod and master cylinder pushrod are different than the ‘92 unit, but the ‘80 master cylinder fits the booster perfectly. Go figure..

 

With all this swapping around, take time to research what the bore size is on the original master cylinder, and then the bore size of the one which you are installing. If you keep the bore size the same, and keep the pedal ratio proper (mounting hole location on the pedal arm) then everything should work out. I have heard about having to file the holes in the master to make the mounting studs fit on the booster.

If you change the bore sizes or the pedal ratio, then you may end up with brakes that require more effort, or brakes which always have a lot of pedal travel. And once in awhile you run into brake line fittings that are different. They do make brass adapters to fix that situation.

 

Correct, the master cylinder determines the pressure put out to the brake system. Changing the bore size can have a positive or a negative effect on pressure seen at the wheels and will dictate the effort required to apply the brakes.

Same with the pedal ratio, if you try to use a vacuum brake pedal with a hydroboost you will end up with a very touchy brake system where any level of touch will be as if you are slamming on the brake pedal. I see it all the time and I keep trying to tell my boss we need to modify the brake pedals with hydroboost because it is transferring too much force with too little effort and is causing this issue.

I couldn't say on the master cylinder fitment to the hydroboost but I do know all the aftermarket ones are using a GM style hydroboost and they all take the old 70s/80s dual reservoir corvette master cylinder. I do not see why there would be a mounting difference between say a '88 F-Super Duty hydroboost master cylinder and a 80 - 86 non hydroboost master cylinder. The bores may change but the mounting pattern should remain the same. Ford wouldn't have changed the mounting pattern on the master cylinder but retain the mounting pattern on the firewall to the vacuum booster.

I don't know because I haven't bought any of the stuff yet to try the swap, I have to wait till I see how much vacuum my engine makes, I hope it makes enough for the brakes to feel like they did with the stock engine, if so then I have no desire of spending the extra money for hydroboost. But if there is a difference worse case you'll have to run a '88 Super duty master cylinder which without a doubt would provide way too much braking for a light duty F100/F150 truck which is why I would not recommend using the Super Duty master cylinder.

On the fittings, we've always gotten AN fittings for the hydroboost to convert them to AN. If I went this way I would most likely just buy the hoses for a 88 F-Super duty and repurpose them for my '82 F150.

 

Well, for some reason they did change the master mounting hole spacing. It's very slight. Just a little bit of filing will make it fit like the other poster mentioned. You see people doing it most often when they want to go from the metal/cast iron master to the later model aluminum master with the plastic reservoir, and put it on the older booster.