Manual brakes vs hydroboost

[747mopar]

I'm in the middle of doing some much needed upgrades to the Charger focusing mostly on handling, one issue is the brakes. My motor produces 15 pounds of vacuum which is enough for my vacuum booster 99% of the time but in certain deceleration situations I have zero boost which will pucker your ***! Yes, I could add a vacuum canister but there's still that possibility and I like 100% fixes so I'm debating hydroboost or manual? I've never driven a classic with manual brakes but have had modern cars with manual brakes and didn't mind them at all, actually liked it.

How is the feel, do you really need to stand on them to lock up the brakes? My only hesitation with the hydroboost is cost and all the messy lines. I've seen master cylinders that claim to reduce pedal pressure as well? Just looking for input.

I already have discs in front and will be adding rear discs at the same time.

 

[Kern Dog]

I could not find a manual brake setup that worked well enough for me with the 4 wheel discs. The caliper volume must have been just too much for the non assist to be adequate to stop a 3980 lb car. I tried it with different master cylinder bore sizes, increased pedal ratio with more leverage too and always ended up with the same thing....firm pedal that took every muscle I had to slow the car down. I could not get the tires to even skid on dirt. I interpreted that is a case of improper leverage to adequately force the calipers to work.
Hydroboost in theory works just the opposite. Many have stated that it works too well where the brakes are touchy and don't give adequate feedback, leading to skids when the driver wasn't expecting nor wanting it. The fix for that is often a really big bore master cylinder to, in effect, desensitize the system some to avoid lockup.
In 2022 I went through my engine and to save money, I reused a still good camshaft that produced low idle vacuum. Of course, this was inadequate to power the brakes so I tried the manual setup as I tried in 2012 and had similar findings. I switched to a Hydroboost that I got from Dr Diff for free in an agreement that I'd do the R & D of it and get to keep it free of charge. I don't know what I did wrong (if anything) because I could not get it to work and in the process of trying, I burned up 3 or 4 power steering pumps. He had me ship it to someone else and supposedly, that guy got it working in his car. I asked later about it and was only told that he got it working but I got no clear explanation as to how he did it.
I currently have a vacuum pump and a storage tank which work quite well although the pump is noisy. You can't hear it when the engine is running but it annoys me enough to anticipate it being GONE when I swap in the next cam in a couple of months.
My preference above all is braking feel like a new car without Band-Aids like vacuum pumps or Hydroboost.

 

[493 Mike]

I have Hydro boost on my 65 and had PS pump issues too. It stems from the pedal not returning or push rod too long. Not finished with fine tuning yet but, it will put you thru the windshield if you want.
Mike

 

[dfrazz]

When I did the 392 Hemi swap in my ‘70 Cuda I went with hydroboost and Wilwood 6 pistons all around. By far the best braking system I’ve had on a classic Mopar. I just tweaked the front/rear prop valve and it was perfect.

 

[33 IMP]

I lost a mono belt on my hydro boost dually when the crank pulley failed. No power steering, no brakes. Almost killed me, and another person I almost ran over.
I DESPISE hydro boost, a really shitty idea. I'll take manual steering, thanks.

 

[Black_Sheep]

I am not thrilled with the performance of manual brakes with front discs, I plan to begin installation of a hydro-boost unit this week. Guys I’ve talked to that have hydro-boost systems have been very impressed with the performance. It is supposed to supply 2000 psi to the wheels. I guess I’ll find out…

 

[Fran Blacker]

I lost a mono belt on my hydro boost dually when the crank pulley failed. No power steering, no brakes. Almost killed me, and another person I almost ran over.
I DESPISE hydro boost, a really shitty idea. I'll take manual steering, thanks.

That sounds like a reason to be scared. Wonder if putting an accumulator with a warning light when pressure is lower than you should have. If light comes on stop.

 

[Project66]

If you prefer power brakes, that's cool, but there are alternatives.

I have a manual Wilwood Big Brake set-up on the front of my Satellite (12 inch rotors, 6-piston fixed calipers, Wilwood MC), with factory 10" drums on the rear and I couldn't be happier. I prefer the feel of good manual brakes, but it might not be the right solution for everyone. It's also less complicated and less expensive than a hydro boost set-up.

 

[Green72]

I know this wasn't part of your question but I had good luck with this vac pump in a similar situation
Bandit Series Brake Booster Vacuum Pumps | Vacuum Brake Boosters
The draw back on this is its pretty big, finding a place for it was a challenge

 

[Kern Dog]

I prefer the feel of good manual brakes.

In many cases, I do too.
I have driven a few disc/drum A bodies with a manual master cylinder and they are fantastic. I just couldn’t get there with my car. My bonehead logic tells me if you have a firm pedal but poor braking performance, you need more pedal leverage than you have. Power boosters do that where leverage cannot.

 

[747mopar]

I lost a mono belt on my hydro boost dually when the crank pulley failed. No power steering, no brakes. Almost killed me, and another person I almost ran over.
I DESPISE hydro boost, a really shitty idea. I'll take manual steering, thanks.

So it's not like losing vacuum to a booster where you can still bring it to a stop or are you saying losing both at the same time was the real problem? Hadn't thought about that but yes, losing power brakes and still being able to steer makes it less scary.

 

[Kern Dog]

When hydroboost fails, you are back to unboosted manual leverage.
This is usually far more difficult than usual manual brakes because a hydroboost setup uses a large bore master cylinder. Mine called for an 1 3/16 or 1 5/32.

 

[747mopar]

I could not find a manual brake setup that worked well enough for me with the 4 wheel discs. The caliper volume must have been just too much for the non assist to be adequate to stop a 3980 lb car. I tried it with different master cylinder bore sizes, increased pedal ratio with more leverage too and always ended up with the same thing....firm pedal that took every muscle I had to slow the car down. I could not get the tires to even skid on dirt. I interpreted that is a case of improper leverage to adequately force the calipers to work.
Hydroboost in theory works just the opposite. Many have stated that it works too well where the brakes are touchy and don't give adequate feedback, leading to skids when the driver wasn't expecting nor wanting it. The fix for that is often a really big bore master cylinder to, in effect, desensitize the system some to avoid lockup.
In 2022 I went through my engine and to save money, I reused a still good camshaft that produced low idle vacuum. Of course, this was inadequate to power the brakes so I tried the manual setup as I tried in 2012 and had similar findings. I switched to a Hydroboost that I got from Dr Diff for free in an agreement that I'd do the R & D of it and get to keep it free of charge. I don't know what I did wrong (if anything) because I could not get it to work and in the process of trying, I burned up 3 or 4 power steering pumps. He had me ship it to someone else and supposedly, that guy got it working in his car. I asked later about it and was only told that he got it working but I got no clear explanation as to how he did it.
I currently have a vacuum pump and a storage tank which work quite well although the pump is noisy. You can't hear it when the engine is running but it annoys me enough to anticipate it being GONE when I swap in the next cam in a couple of months.
My preference above all is braking feel like a new car without Band-Aids like vacuum pumps or Hydroboost.

I have Hydro boost on my 65 and had PS pump issues too. It stems from the pedal not returning or push rod too long. Not finished with fine tuning yet but, it will put you thru the windshield if you want.
Mike

I hadn't really heard of any complaints regarding Hydroboost until now, I'll definitely take this into consideration. I vacuum canister is starting to sound a lot more appealing lol.

 

[747mopar]

When I did the 392 Hemi swap in my ‘70 Cuda I went with hydroboost and Wilwood 6 pistons all around. By far the best braking system I’ve had on a classic Mopar. I just tweaked the front/rear prop valve and it was perfect.

View attachment 1823011

This is what I typically hear.

 

[747mopar]

When hydroboost fails, you are back to unboosted manual leverage.

Is that any different than a vacuum booster failure is what I'm asking? I can stop mine without vacuum but it isn't pretty!

 

[747mopar]

If you prefer power brakes, that's cool, but there are alternatives.

I have a manual Wilwood Big Brake set-up on the front of my Satellite (12 inch rotors, 6-piston fixed calipers, Wilwood MC), with factory 10" drums on the rear and I couldn't be happier. I prefer the feel of good manual brakes, but it might not be the right solution for everyone. It's also less complicated and less expensive than a hydro boost set-up.

I've only had manual brakes on smaller more modern cars so I can't say whether or not I like them on an old Charger.

 

[Kern Dog]

That is the issue. Vacuum boosted master cylinders are often larger bore but not as large as is called for with hydroboost.

 

[33 IMP]

When mine failed (I heard the clang,thump,thump as the outer ring of the lower pulley broke off and rolled across the street, and tossed the belt, but I didn't know what it was)
I tried to change lanes and realized power steering was gone, so I tried to pull over to the curb. By the time it was clear, I decided to pull into a gas station. Then I realized I had no brakes either. There was lots of pedal , but it sure wasn't stopping!! Fortunately there was an empty island I could muscle the runaway truck thru, without killing the patron who almost stepped in front of me.
I finally got my wits about me and stomped the e-brake and stopped about two feet away from a parked car at the edge of the lot.
Had it towed home, replaced the crank pulley with the re-reinforced third revision of the ones that were breaking. ( I wonder how many lawsuits were paid out, and hushed up, about cars in accidents with no steering or brakes?)

 

[Project66]

In many cases, I do too.
I have driven a few disc/drum A bodies with a manual master cylinder and they are fantastic. I just couldn’t get there with my car. My bonehead logic tells me if you have a firm pedal but poor braking performance, you need more pedal leverage than you have. Power boosters do that where leverage cannot

Yeah, I was heavy into sportbikes about 25 years ago and that probably skewed my perceptions about things like front-end feel and traction. I know I'll probably never get all the way there with my old Satellite, but I am really satisfied with the brakes. I bought my brake kit from Summit, but I was on the phone more than once with Wilwood customer service. They helped me find the right MC for my set-up. My brakes will definitely lock all 4 wheels without going to the floor, but they might be a bit heavy for people who are not bent the way that I am.

I'm working on the front-end with my latest round of mods. I just added a sway bar and 1.03" torsion bars which should greatly improve the F/R balance against my Cal-Trac rear springs. I went with the CalTracs because I could not seem to find any other springs to raise the rear for less than $700. It's been a challenge finding a set-up that minimizes the rub from my 17" front wheels without making the car look like a low-rider. I like the stance with the CalTrac +1 springs. Now I'm gonna have to start over with the new torsion bars. I'm worried that the bigger torsion bars will ruin the weight transfer when I get on the brakes. We'll see what happens.

 

[OneWheelPeel]

I lost a mono belt on my hydro boost dually when the crank pulley failed. No power steering, no brakes. Almost killed me, and another person I almost ran over.
I DESPISE hydro boost, a really shitty idea. I'll take manual steering, thanks.

That’s what’s always worried me about that setup. One thing I’ve wondered about is on my old LandCruiser the MC is electrically boosted, maybe someone out there is retrofitting a setup like that into old cars?