Interesting…..hydroboost is used on low vacuum output engines. Vacuum boost works fine in most vehicles and does not depend upon hydraulic pressure systems to power BOTH brakes and steering. I did not note any sponginess in braking which would indicate compressible air within the steering and braking system. UR using hydroboost on your truck since the engine is hi output….low vacuum. I can’t trust hydroboost with the hose connectors furnished in your kit for over 200$. Why do I like my braking on an 8 inch dual diaphragm better than hydroboost? Air in the system is the only reason I can think of….yet there was no sponginess or steering issues until I braked hard into a turn. I can ask Joe Pavandano (sp?) about this issue.From: JC Genty [mailto:jc@performanceonline.com]
Sent: Monday, December 10, 2018 12:46 PM
To: Carroll Hird
Subject: Re: FW: RETURN Not being there during the install, I can't say why you are having the issues you are. The Hydro-Boost is a far superior set up vs the vacuum booster. If it wasn't, all the big auto manufactures would still be using vacuum. The jerking you experienced while braking and cornering tells me that there is still air in the system. The Hydro-boost system needs to be bled just like a brake system, but requires more time to do so. I don't think your gear box upgrade would have had anything to do with it as we are running a quick ration box as well. Our truck is also running a type 3 p/s pump as well as 4 wheel disc brakes. JC Genty
General Manager
Performance Online Inc. (POL)

 

I'd be worried about this clown. The OEMs still use vacuum for a reason, and, any time you blame someone else in your first sentence, it implies you are not ready to ever accept fault.

 

I agree!!

 

One-box, vacuum-less braking is a reality, and coming to more platforms in the coming years. Especially true with the Big 3, not so much yet with JOEM's.

 

Yeah, because it's cheap. Fewer moving parts, lower cost to make, lower cost to install.

The reality is that there are literally millions of one ton trucks on the road with hydroboost from the factory. They are completely reliable. I've had a vacuum brake booster fail when a carb backfire blew apart the plastic check valve in the booster. I've never had a hydroboost system fail. Keep in mind that both the vacuum and hydroboost systems are designed to provide boost for one or two stops even if the engine stalls. The check valve in the vacuum booster keeps vacuum in the canister (assuming, of course, that you don't explode the plastic check valve...) and the accumulator on the hydroboost retains a hydraulic pressure reserve for that system.

As for the "one box" systems, GM used the one box Powermaster system in the 1980s on many cars, including the Grand Nationals. An electric motor driven pump in the master cylinder pressurized brake fluid to operate a small hydraulic booster built into the M/C. As with every new technology GM tries for the first time, it was released to the public before it was fully baked, resulting in problems and bad press. Naturally by the time they got it right, the public didn't trust it. Vacuum boosted systems will fall out of favor as cars move to hybrid, full electric, diesel, and other technologies that no longer provide a constant source of vacuum. The same thing happened to mechanical engine cooling fans - it's tough to use a mechanical fan on a transverse engine.

 

I think we'll see fully electric soon.