Dr. Diff Hydroboost

[Charlie Brown]

I see that Dr. Diff is now offering a hydro boost system for our Mopars. I was wondering if anyone has installed one of his units and if so, your opinion on the product.

 

[Fran Blacker]

@Kern Dog

 

[Kern Dog]

@Kern Dog

It was a debacle.
In 2022 I was offered a Hydroboost unit to install, test and report on. It was an informal "Research and development" project where I was given a HB unit and asked to install it in my 1970 Charger, get it working and then report back to Dr Diff on what it took to make it work and how well it did.
I hate to lose. I'm not one to give up easily so take that into consideration as you read on.
It was my responsibility to find a way to build pressure and return lines for the system. I had to find a power steering pump to use that had adequate pressure and a dual return line since Hydroboost uses power steering pump pressure to function. Dr Diff provided what help that he could but admitted that he was new to this system and was relying on me to work out the details.
The unit that he sent me fit fine and looked great. DD did have a suggestion for a master cylinder that was relatively cheap from Rock Auto. I found a power steering reservoir from a 1990s Chevy 1 ton 454 truck. It had a larger reservoir and two return lines. I made my own lines for the system and had help from a local hydraulic shop with the fitment and crimping.
First off, I had an impossible time getting the HB to ever provide boost. From the very first start up, the steering was not boosted enough and the brakes were unboosted. I made sure that the lines were connected like they are supposed to be according to pictures and instructions that I found elsewhere on the internet. While trying to bleed the system, (according to procedures that I researched online) the power steering got worse and worse due to a failing pump. The pump was working fine before beginning the installation of the HB unit. I swapped in another pump into that reservoir and started over. THAT pump conked out too. I went through 3 pumps,( maybe 4? The memory is a bit fuzzy as I was as frustrated as I have ever been) 2 or 3 of them new/rebuilt units and one good 4 year old unit. I emailed Dr Diff a few times as he was never available to take calls due to either being otherwise busy during the Covid era (Summer 2022) where lots of people just quit working or other reasons that I never learned. He did respond to emails but nothing that I tried made a difference. The system kept killing power steering pumps while providing NO boost at all. I tried several bleeding procedures, watched numerous YouTube videos and asked other guys that I knew and nobody could help. Finally, I pulled the system and shipped it to someone else that Dr Diff was in contact with. I was curious as to what happened with that guy and after a few attempts to find out, I got a response that he got it working but almost no details as to what he did to get there. The whole experience was a disappointment. I was curious about the advantage of the system since it is used in some heavy trucks with great success. From what I read and heard, It is a great workaround to engines with little or no vacuum.
I have thought about revisiting the whole thing but would need a LOT MORE reassurances as to how the system goes together to ensure a successful installation. Maybe Dr Diff learned more from the second guy and was able to package together a system with confidence that it will work. I appreciate the opportunity but felt like a man on an island where almost every obstacle was up to me to solve and since I was unfamiliar with the system, unable to test it on a bench or anyplace other than while in the car, I got tired of swapping power steering pumps only to get the same results.
IF the kit comes with clear instructions on hydraulic line installation and bleeding procedures along with a detailed FAQ and troubleshooting guide, you'll have it better than I did.

 

[vance.dykes]

if you have the time go to a you pull parts salvage yard and remove a working system and install on one of your mule cars and see what happens Kern ?

 

[multimopes]

Dang Greg, It's nice that you voluntarily did that, but I hope that you received some compensation, (other than a warm fuzzy), for your time & work! Even a picture of a hand to print out & paste
on the wall to lean against for a free pat on the back!

 

[Kern Dog]

Like I stated, I hate to lose. I don’t give up easy. I tried and tried but kept hitting a wall. I have A/C so changing pumps each time was difficult. Each time I pulled the pump, I had to also pull off the pulley and the reservoir. Add in the $15 a quart power steering fluid this Borgeson unit needs.
I am not an egotist that thinks that if I can’t figure it out that nobody else could.
If another guy got that system working, I want to know what I did wrong to learn from it. What I got was some cryptic and abbreviated message about how the other guy has it working as intended. That wasn’t any help.

 

[multimopes]

That sucks! You could have slipped and injured yourself badly. Also you can never get back the time you put into that work either! There are few people who that would have voluntarily done what you did without some kind of compensation!

 

[zyzzyx]

I'm not an expert but instead of going through all of that, couldn't we install a vacuum pump that
comes on a whole variety of cars and trucks (Like Diesel) that need one, and put a power brake
booster in? Tesla even has a really neat one. No need to spend Mega Bucks on an aftermarket
"High Performance" unit! Whaddaya Think?

 

[Kern Dog]

My compensation was a FREE Hydroboost unit.
I don’t blame Cass/Dr Diff. He made the offer, I accepted it. I really don’t like this new business model of email or internet sales only. I like to talk to vendors. When a problem like this occurs, it feels to me like back and forth emails is inferior to a 5 minute phone call. Again, I can sympathize with time constraints that vendors face. I’m also familiar with how strained we often were during the Covid era where it was hard to get people to get off their asses and get to work.
Still, I got tired of the same exact routine of install new pump, having power steering working fine, bleeding the system and before I could even finish that, the steering boost started failing a bit at a time. I never got the HB to provide any boost ever.
Time spent was not what annoyed me. I love working on these cars. It was losing without having any real help that pissed me off. If I were an idiot that had a lot of great advice that I were too stupid to follow, that would be my own fault. That was not the case.
Call it obsession but I often harken back to mistakes that I have made in various things in life. I want to know where I went wrong and learn from it. This issue is still unresolved for me.
I did notice that one of the tubes on my power steering fluid cooler had a slight kink to it and wondered if it was a contributing factor. I dismissed that based on the fact that in my case, as the boost for steering seemed to fade away, I never had the typical grinding sound that the pump makes when it is low on fluid. Saginaws are what I am most familiar with and when they are low or starved for fluid, they howl with a distinctive noise. I never had that sound. The fluid was always real dark each time I changed the pump, indicating heat damage or some weird contamination.

 

[vance.dykes]

My compensation was a FREE Hydroboost unit.
I don’t blame Cass/Dr Diff entirely. He made the offer, I accepted it. I really don’t like this new business model of email or internet sakes only. I like to talk to vendors. When a problem like this occurs, it feels to me like back and forth emails is inferior to a 5 minute phone call. Again, I can sympathize with time constraints that vendors face. I’m also familiar with how strained we often were during the Covid era where it was hard to get people to get off their asses and get to work.
Still, I got tired of the same exact routine of install new pump, having power steering working fine, bleedining the system and before I could even finish that, the steering boost started failing a bit at a time. I never got the HB to provide any boost ever.
Time spent was not what annoyed me. I love working on these cars. It was losing without having any real help that pissed me off. If I were an idiot that had a lot of great advice that I were too stupid to follow, that would be my own fault. That was not the case.
Call it obsession but I often harken back to mistakes that I have made in various things in life. I want to know where I went wrong and learn from it. This issue is still unresolved for me.
I did notice that one of the tubes on my power steering fluid cooler had a slight kink to it and wondered if it was a contributing factor. I dismissed that based on the fact that in my case, as the boost for steering seemed to fade away, I never had the typical grinding sound that the pump makes when it is low on fluid. Saginaws are what I am most familiar with and when they are low or starved for fluid, they howl with a distinctive noise. I never had that sound. The fluid was always real dark each time I changed the pump, indicating heat damage or some weird contamination.

you sir are a man after my own hart. to work so hard and not get the answers is not worthy of your efforts . after reading your post for a few years i think you did great hope you get the info from them some day. keep it up Kern

 

[Kern Dog]

I'm not an expert but instead of going through all of that, couldn't we install a vacuum pump that
comes on a whole variety of cars and trucks (Like Diesel) that need one, and put a power brake
booster in? Tesla even has a really neat one. No need to spend Mega Bucks on an aftermarket
"High Performance" unit! Whaddaya Think?

Yes, they do work.
Camshafts that result in low idle vacuum leave people with little choice but to take alternative measures.
I liked the more compact appearance of the HB unit and the concept of having brakes far better than I had before was interesting.
I have a 4 wheel disc setup that requires some type of assist. I have tried manual master cylinders and it takes way too much pedal effort to stop the car, far more than I was comfortable with.
I never took the car out on the road with the hydroboost because it was completely ineffective in my car. I did drive it using first a 1.03 then a 15/16” manual master cylinder and those did stop the car but nowhere near what you’d consider safe and adequate.
Currently I have a stock replacement B body dual diaphragm booster, a 15/16” MC, a vacuum pump and storage can. It all works but the pump is noisy.

 

[vance.dykes]

Yes, they do work.
Camshafts that result in low idle vacuum leave people with little choice but to take alternative measures.
I liked the more compact appearance of the HB unit and the concept of having brakes far better than I had before was interesting.
I have a 4 wheel disc setup that requires some type of assist. I have tried manual master cylinders and it takes way too much pedal effort to stop the car, far more than I was comfortable with.
I never took the car out on the road with the hydroboost because it was completely ineffective in my car. I did drive it using first a 1.03 then a 15/16” manual master cylinder and those did stop the car but nowhere near what you’d consider safe and adequate.
Currently I have a stock replacement B body dual diaphragm booster, a 15/16” MC, a vacuum pump and storage can. It all works but the pump is noisy.

try a ford vacuum pump with brackets as they are rubber mounted. 2006 f-250 with a 6.0 diesel

 

[Kern Dog]

I might try that. Maybe even move the pump to the other side of the car. Right now mine is behind the drivers side headlights.
Mine does have rubber cushions where it mounts but the dude just sounds like a Harbor Freight oiless air compressor.

 

[vance.dykes]

I might try that. Maybe even move the pump to the other side of the car. Right now mine is behind the drivers side headlights.
Mine does have rubber cushions where it mounts but the dude just sounds like a Harbor Freight oiless air compressor.

the pump on the ford is for the hvac system so not very big but will run for ever . not loud as i will have to go to them to check they are working so not sure they will have the volume you will need . the other one that comes to mind is the vacuum pump that GM used on the Oldsmobile 350 for the brakes and other accessories. my brain is going thru some thoughts look at diesel trucks they will have the style pump you would need might go back to the 1960,s

 

[OMTWF-72SE]

I've tried different styles of vacuum pumps attempting to reach this same thing and finally settled on the LEEDs pump. I know there are others. I mounted that and the air tank in the void area of the cars nose in front of core support over by the void where the horn is mounted. I only notice when I first turn on the key, then once the car is started and driving I've never noticed it. I mounted it out there after driving in a charger with it mounted down low on the firewall. that was horrible.

 

[themechanic]

Yes, they do work.
Camshafts that result in low idle vacuum leave people with little choice but to take alternative measures.
I liked the more compact appearance of the HB unit and the concept of having brakes far better than I had before was interesting.
I have a 4 wheel disc setup that requires some type of assist. I have tried manual master cylinders and it takes way too much pedal effort to stop the car, far more than I was comfortable with.
I never took the car out on the road with the hydroboost because it was completely ineffective in my car. I did drive it using first a 1.03 then a 15/16” manual master cylinder and those did stop the car but nowhere near what you’d consider safe and adequate.
Currently I have a stock replacement B body dual diaphragm booster, a 15/16” MC, a vacuum pump and storage can. It all works but the pump is noisy.

The new pumps are quiet but expensive, although not nearly as high as a hydroboost system.

 

[OMTWF-72SE]

The new pumps are quiet but expensive, although not nearly as high as a hydroboost system.

I don't disagree with the expensive part, but I will say that a 20 atmosphere vacuum on a standard booster in my 72 is very noticeable versus the normal vacuum approach from the stock brakes that at best were carrying about 11 with my 440. However, if you are a pedal tapper the vacuums won't work well because you never build up holding pressure. I think of it as a boosted until fade then manual type feel. stops me fine from points north of 85mph, the nose dive on the 72 is scarier than the braking.

 

[HEMIB]

View attachment 1775055

It was a debacle.
In 2022 I was offered a Hydroboost unit to install, test and report on. It was an informal "Research and development" project where I was given a HB unit and asked to install it in my 1970 Charger, get it working and then report back to Dr Diff on what it took to make it work and how well it did.
I hate to lose. I'm not one to give up easily so take that into consideration as you read on.
It was my responsibility to find a way to build pressure and return lines for the system. I had to find a power steering pump to use that had adequate pressure and a dual return line since Hydroboost uses power steering pump pressure to function. Dr Diff provided what help that he could but admitted that he was new to this system and was relying on me to work out the details.
The unit that he sent me fit fine and looked great. DD did have a suggestion for a master cylinder that was relatively cheap from Rock Auto. I found a power steering reservoir from a 1990s Chevy 1 ton 454 truck. It had a larger reservoir and two return lines. I made my own lines for the system and had help from a local hydraulic shop with the fitment and crimping.
First off, I had an impossible time getting the HB to ever provide boost. From the very first start up, the steering was not boosted enough and the brakes were unboosted. I made sure that the lines were connected like they are supposed to be according to pictures and instructions that I found elsewhere on the internet. While trying to bleed the system, (according to procedures that I researched online) the power steering got worse and worse due to a failing pump. The pump was working fine before beginning the installation of the HB unit. I swapped in another pump into that reservoir and started over. THAT pump conked out too. I went through 3 pumps,( maybe 4? The memory is a bit fuzzy as I was as frustrated as I have ever been) 2 or 3 of them new/rebuilt units and one good 4 year old unit. I emailed Dr Diff a few times as he was never available to take calls due to either being otherwise busy during the Covid era (Summer 2022) where lots of people just quit working or other reasons that I never learned. He did respond to emails but nothing that I tried made a difference. The system kept killing power steering pumps while providing NO boost at all. I tried several bleeding procedures, watched numerous YouTube videos and asked other guys that I knew and nobody could help. Finally, I pulled the system and shipped it to someone else that Dr Diff was in contact with. I was curious as to what happened with that guy and after a few attempts to find out, I got a response that he got it working but almost no details as to what he did to get there. The whole experience was a disappointment. I was curious about the advantage of the system since it is used in some heavy trucks with great success. From what I read and heard, It is a great workaround to engines with little or no vacuum.
I have thought about revisiting the whole thing but would need a LOT MORE reassurances as to how the system goes together to ensure a successful installation. Maybe Dr Diff learned more from the second guy and was able to package together a system with confidence that it will work. I appreciate the opportunity but felt like a man on an island where almost every obstacle was up to me to solve and since I was unfamiliar with the system, unable to test it on a bench or anyplace other than while in the car, I got tired of swapping power steering pumps only to get the same results.
IF the kit comes with clear instructions on hydraulic line installation and bleeding procedures along with a detailed FAQ and troubleshooting guide, you'll have it better than I did.

Must have been unlucky to have 3 x failed pumps if the fluid circuit was correct & the output of the pump was blocked the pump would load up & get extremely hot ,if it was flowing correctly it should not hurt the pump it is also possible the hydroboost was faulty i have installed 6 of these units both new & junkyard the only problem i have had is the pedal not returning correctly. It would be good to get to the bottom of Hydroboost install issue as a lot offer people have spent many hours on them without success. Also with drum brakes on the rear you will get a lot of pedal travel due to the slave cylinder rods retracting when the brake is released where Disc brakes have very little movement when released ,i also tried a 10lb residual valve with little success.

 

[themechanic]

I just watched this video yesterday and he's had his hydroboost for years.

 

[Kern Dog]

Here is the graphic that is displayed on the Dr Diff site:

It differs a bit from the unit that was shipped to me. In this graphic, the blue colored accumulator is toward the fender, mine was toward the engine.

That may not matter but to get the accumulator on the other side, the unit can be rotated 180 degrees. This would put the hydraulic fittings on the bottom which doesn't make sense to me.
Help me out here...This was my final installed setup:

Letter A is pressure from the Power Steering pump.
B is pressure from the HB unit to the power steering box.
C is the return line from the HB to the power steering pump reservoir.
What isn't shown is the other return line.....the original from the PS box back to the cooler, then to the pump reservoir.
Do you see anything wrong with the way these are routed?