Hydroboost conversion done!
 

So I got really tired of the braking system on my 76 F-250 SuperCab 2WD:mad:. I had replaced everything multiple times and it still was not that good. So I decided to do a HydroBoost conversion. Some people put way to much thinking effort into this conversion but its really is not that hard. I decided to just jump into it and get it done!All the parts I used can be found at a local parts store or junkyard I got mine from a junkyard.:-jammin

Parts list
F-450 HydroBoost found on the F-SuperDuty trucks $24.00
HyrdroBoost mounting bracket from F-450 $2.00
Both pressure lines from the F-450! $19.00
Master Cylinder "NEW at NAPA" for 79 F-350 SuperCab $31.00
Power Steering Pump from the F-450 $ 20.00
Bulk High pressure 3/8'' oil cooler hose 6' $28.00

That will give you the main parts you need to get. Other parts such as clamps and oil are common sense. The install went very well and almost ZERO fab work. First remove the pushrod from the brake pedal inside the truck.Make sure you keep the stock bolt, bushing and nut you will be reusing these. Now go and remove the master cylinder and set it aside. Start unbolting the vacuum booster, start by removing the 4 nuts on the rear of the unit that hold it on to the brackets. Now remove the two brackets that held the booster to the firewall and keep the bolts you will reuse them. Go ahead and remove the black plastic dust cover that mounted between the booster and the firewall and discard. You now have a fresh start all the parts are off the truck and you are ready to mock up the HydroBoost.First start by removing the 4 studs in the HydroBoost bracket and discard them. The F-450 mounting bracket has to be removed from the HydroBoost and flipped 180 degrees to do this remove it and you will see a small tang. Just make sure you do not flip the bracket the flush side without the edges goes towards the firewall. Notice how the factory just cut a groove in the threads on the rear of the HydroBoost for the tang to fit. Go ahead and cut a new slot on the other side and make sure it is straight if not your booster will sit crooked. Now go ahead and put the mount back on the rear of the HydroBoost and tighten the nut and put the snap ring on. Take two of the stock bolts that went to the firewall and put them in the top 2 holes of the HydroBoost now bolt the hydro boost to the firewall. You will notice the bottom two holes need to be slotted upwards, mark them with a pen and remove the booster. Use a die grinder and create the slots in the bracket. Once done put all 4 bolts in and tighten down. Go inside and hookup the pushrod to the pedal. The pushrod has two sides to it one is flat the other has a bump you want the flat side towards the pedal. Reuse the stock bolt bushing and nut and tighten. Go and start running the pressure lines, the stock HydroBoost line will thread into your stock steering gear so no problems there. You will have to get creative and do some gentle:-X21 bending of the tubes to adapt them to fit in these trucks. But they will fit. So one line goes from the pump to the left hand port on the HydroBoost then the right hand port goes to the steering gear. Depending on if you got the power steering pump with two return lines will determine how you will have to run the return lines. Run one return line from the stock PS cooler output to the pump then run the HydroBoost return line to the other return port on the pump (if you don't have 2 return ports on the pump just tee all 3 lines together). You're almost done go ahead and fill the PS reservoir (you may have to do it a few times after initial start once the are bubbles work their way out) bleed all the brakes. Go ahead and start the truck and check for leaks and test out your new braking power!:-jammin

pictures please.. and to think i was gonna put a chevy hydroboost in, maybe i should just sell that and guy the ford version.

I will get some pictures up. You can use a hydroboost from a chevy. Get one from a 99 astro van its the same size and has the same hookups and can be had for 99.00 at parts stores. the only downfall to that is the pushrod is too long and has to be customized.

http://i29.photobucket.com/albums/c2...h_DSCF0572.jpg
http://i29.photobucket.com/albums/c2...h_DSCF0573.jpg
http://i29.photobucket.com/albums/c2...h_DSCF0574.jpg
http://i29.photobucket.com/albums/c2...h_DSCF0575.jpg
http://i29.photobucket.com/albums/c2...h_DSCF0576.jpg
http://i29.photobucket.com/albums/c2...h_DSCF0579.jpg
http://i29.photobucket.com/albums/c2...h_DSCF0580.jpg

You can see how well the push rod connects to the stock brake pedal!

Hey, a chance for me to learn something! Hydroboost means that you stop using the vaccuum canister and put on some kind of hydraulic assist device? You tie into your power steering, then, to make it work.

I have the regular vac assist with 2 piston calipers and it seems fine. Are you towing big loads? Or why were you not satisfied before?

Thanks!

Just the fact it took way too much pedal effort to get decent braking. Put it too you like this I did some 60-0 braking tests

Stock brake system
60mph-0mph 258 feet

HydroBoost
60mph-0mph 164 feet

Neither of the tests did the brakes lock up and both tests were unloaded and the truck scales at 7260 lbs.

That is an amazing improvement! Jeez. My wife has a Mini and it stops like you threw out an anchor. I have to admit, that kind of stopping power is awesome.

I am going to look into this!

Cool write-up.

I had started looking at doing my hydroboost and got distracted by other projects on the crew. But since you just did this and it is fresh in your mind I will ask some questions that will help me decide how I will end up doing mine:p

1 - does your brake pedal sit higher now that you have the hydroboost in?

The reason I ask is I took some measurements when I pulled both the stock vacuum booster and bracket, and then the hydroboost (pics 1 & 3 below)
Based on my measurements - from the bracket where it attaches to the firewall to the center of the pushrod hole - the hydroboost pushrod was 1.25" longer. I would think this would make the pedal sit higher than stock.
To correct this I was going to make a 1.25" thick aluminum spacer/adapter that will convert the bolt pattern from the hydroboost to the firewall. This should allow the pedal to stick at stock height and still have the correct throw.

I have it drawn in cad, but not cut yet.


pics below or stock vs. stupid duty hydroboost. I figured these will help the thread since you didn't have any pics of the hydroboost before it was in your truck.

Stock
Attachment 204157
Attachment 204158

Hydroboost
Attachment 204159
Attachment 204160

Side by side
Attachment 204161

For the record my hydroboosts (I bought 1 for each of my 74's) are off of 2001 or so F-250s (not positive what year that came off of as I didn't pull them). From what I have read/heard, the hydroboost units are the same from about 99-07 in F-250s thru F-450's or 550's. I don't know if the bracket that conects them to the firewall is - but it may be.


Oh - and I will be using the stupid duty master cyl. that came on the hydroboost to see how that works on these trucks:-drink

Thats pretty cool. Didn't even think it would work. Learn something new everyday.

Sort of a given but I mention it anyway. The 5.4l and 6.8l gasser SDs don't have the hydro brake setup they use vaccum asist. So you'll want to target the diesel SDs only for parts.

Thanks for adding that. I was thinking that was a given and people would know - but we're better off making it 100% clear:-D

Chase,

The pedal on mine sits about 1'' higher and is ok with me. The master cylinder you have from the super duty will only work if you have disc brake rear otherwise use a 79 master cylinder.The superduty master will try and move too much fluid and will cause the proportioning valve to close.Not too mention the SD master has the brake lines exiting towards the engine the 79 master exits towards the fender so you can reuse your brake lines.

Nice write up this will make a good winter weekend project. Thanks

Good points.

I forgot to mention - YES I will be going to rear disks on both the crew and the supercab.

As for re-using the stock hard brake lines - mine on the crew are a fugly redo job by the P.O. so I want to clean them up anyways, but for most people looking to do this swap on a stock truck - you are right - the stock master might be a better choice.

Thanks for the info!


Why wait? This is pretty esily done in a weekend!

What do you guys think of using the superduty master and an adjustable proportioning valve? I am thinking of going with hydroboost eventually because I have rear discs on my 74 f100 and I think it would clean up the engine compartment quite a bit.

I think an aftermarket adjustable proportioning valve would be fine. Wilwood makes both ones that are a knob type that you turn clockwise or counterclockwise to adjust as well as a handle/lever type.

Thats kind of what I had in mind. Since I welded in the MII and new crossmember, I am not exactly sure how things are going to fit when I build motor mounts for my 460. So I am keeping my eyes out for hydroboost parts just in case. Plus, I am not exactly sure how much vaccumm I will have and I want to eliminate the bean can.

I spent 6 hours start to finish thats including the 2 hour trip to the u-pull to get parts.:-D

you could always make new brackets instead of using a spacer, i think it would look better, it would look as though the truck actually came with hydroboost.

I drive a 1978 Mercury Grand Marquis that has 4 wheel disc brakes with hydroboost and it stops very nice so I wonder how well a hydroboost from a fullsize 4 wheel disc 1975 to 1978 Lincoln or Mercury Marquis or Ford LTD would fit these trucks?

it may work, but it also may not output enough pressure.

Marquis
 

I had a 76 that I was going to use the Hydroboost from several years ago..ended up selling the whole car...those cars are very heavy and the unit should work just fine for a truck unless it built insanely huge....Superduty units are just easier to come by now...and a little more modern.

Of course my car is my daily driver and a nice car so I would never use it for a donor and they are heavy, it weighs 4,700 pounds.

Not to toot my own horn, but you apparently haven't seen my work.;) Machined aluminum will look just fine (I bought the aluminum block/billet today):-D
As for looking as if the truck came with one... I strive in all of my work on the trucks to look BETTER than it did coming from the factory. I think I'm doing ok at pulling that off as well.
Factory "brackets" were an L bent piece of steel. I'll take a machined piece instead most of the time.

I haven't run an old hydrobbost before but from what I have heard the new units seem to function a bit better. Plus, based on other responses here - the new ones sound a little smaller/more compact.

i am not doubting the quality of your work, i personally like things to look as they would have if ford did it. thats just my preference. :)

And I'll stick with BETTER quality than rolled off the assembly line:-X22

Not going to split hairs some of the things ford did was fine but other parts of these trucks you just have to sit back and think what were they smoking? The really bad pedal bushing design, firewall flex at the booster and the fuse box which uses such uncommon and hard to find fuses. So if you can find a part you can make better than stock I say go for it.

I'm confused, does one PS pump run the brakes and steering or do you need two pumps?

usually its one pump, but you could use 2, for a safety factor.

I want to drive my truck first, maybe after everything is finished with my conversion I'll take a weekend to do this job. I live in Illinois and won't drive my truck after the salt hits the road so that leaves me roughly until December to drive my truck if I ever get time to finish it.

Oh and for the record Chasetruck, the pics of your work toot your horn for you.

Gashog the prices that you quoted are the junk yard prices or did you get them at a parts store, if so where? Do you have any part numbers?
My 79's brakes were pretty jacked from the PO and my plan is to do alot of hauling and towing with 37's so a little extra stopping power would be great.
Why did you do the snap rings? If your worried about the bolts backing out way not do lock-tight or a jam nut and lock-tight. Just curious.

Thanks for the post.

The only part I got from the parts store new was the master cylinder.But all the parts I listed can be had new or rebuilt from any parts store.

These are the prices for new parts

190.00 + 50.00 core on F-450 Hydroboost with bracket
Pressure hose pump to booster 19.00
Pressure hose booster to steering gear 22.00

Aren't the diesel hydroboost units the same for F250-F550?

Josh

No, that is the part I think people are missing. You need to get it from a 87-97 F-450 SUPERDUTY truck those were the only ones that had hydroboost. There also was no 550 back then. You can use 98+ Super Duty parts but more fab work is involved.

Do you know what the differences are?

The one in your pics look pretty identical to the units I have which are both 2001 or newer. From what I can tell there isn't much fabrication that would be different. It looks like I could install mine the way you did yours. I am just making a bracket/spacer to keep mine off the firewall as I don't really want my pedal pushed over an inch higher.

Pre 2001 Booster:

http://partimages.genpt.com/partimages/769906.jpg

Post 2001 Booster:

http://partimages.genpt.com/partimages/905497.jpg

Besides the pushrod, what else is different?

Josh

The later one doesn't have the green bolt.

That's just a plastic plug for shipping

Ok so it looked like a bolt...

The pre 2001 bolt spacing on the bracket is different its a metric spacing. It can work just with some fab I guess.You could also redrill the 3/8'' bolt hole in the pedal so the pedal does not sit so high instead of a spacer.The pushrod on the booster moves up and down a lot so you can relocate its mounting point on the pedal.

Did you mean POST 2001 booster?

I forgot to mention that according to NAPA there is a $100 price difference between the two as well... $139 for Pre 2001 and $239 for Post.

I only bring up the Post 2001 booster because it is actually easier to find wrecked Superduty F250-F350 trucks than it is to find an F450 around here.

Josh

Please excuse me but I have a couple simple questions and this is the first I'v heard of this upgrade.

1. Do the brakes revert back to manual if the engine stalls?

2. I'm still wondering the purpose of the snap rings.

3. With the addional use of power steering pump and oil is a cooler needed?