There is a How-To on hydroboost in the How-To section with more detail. You can get the booster pump from various later model Ford trucks (late 90 Super Duty more or less, if I recall), or buy a reman/new one from a 1997 F350 (Motorcraft #BRB37 for the top-of-the-line new ~ $250). These bolt directly to the firewall where the vacuum booster does now, same bolt pattern. You can use your existing master cylinder, also same bolt pattern.

Then you just need to run some extra hoses. The only complication appears to be the brake pedal - on the Super Duties the pin that actuates the pushrod on the power booster pump is about an inch or so higher than on our trucks, this needs to be changed. Here is a post that talks about it.

The Bronco/diesel guys have used both the Saginaw/CII pumps without modification so I don't think you need to change anything there. You just need a second return line for the hydroboost pump. Some people just T the HB return into the PS return line, and apparently this also works, but others say that is not a good idea, as any sort of back-pressure on the HB pump may cause the brakes to drag, and the PS return could create some back-pressure.

Anyway I don't want to hijack your Engine thread on steering/brake stuff...

As to whether you need it or not - probably not. But if you ever thought you might want it, for whatever reason, now would be a good time to think about the second return to the pump since you are messing with it anyway.

 

The downside to hydroboost, lose the PS belt, or a PS hose, and you lose the booster function.....
At least a vacuum booster will hold vacuum if the engine dies/is cut off. May only give you 1-2 uses before the vacuum is gone, but that's better than none.

 

Hydroboost HAS TO have a pressure reserve "accumulator" (by law)

Your argument is invalid.


http://dave78chieftain.zxq.net/hydroboost_brakes.html

 

Jim, you are exactly right. My 78 Olds Delta 88 Royale diesel had a large gold colored can protruding from it, this was the accumulator. You had to make several full applications to depressurise it before servicing. The 80 Pontiac Bonneville diesel had the accumulator internal as does the 81 Buick I haven't scrapped yet.

 

O, I've read the How-To as well as everything else I can find on hydro-boost. It is pretty well agreed that it can supply more pressure when you stomp the brake pedal. But I don't understand the rationale for it when the vacuum system can supply enough pressure to lock the wheels. I understand the need on a diesel or an engine with low vacuum at idle, but mine is not one of those. What am I missing?

 

Gary, has Tim tested the vacuum on your setup? If the cam is too agressive, the manifold vacuum will suffer. This would cause the booster to not be as effective. That's the main reason to switch. Also, it would cut down on the vacuum lines in the engine bay.

 

That's why we don't run a booster on the race car. It'd never be able to power it the cam is so radical.

On a truck I could see having too radical a cam that doesn't provide enough vacuum. I don't think that Gary will have that problem. It takes a pretty radical cam to prevent the vacuum from building up that it won't power a brake booster.

 

It's true you can lock up the wheels even with the vacuum system, but one advantage to hydroboost is the foot feel - the same amount of stopping power can be achieved with less effort on the pedal.

In my case I can lock the wheels, but I really have to put some muscle into it. Even just in regular driving when I'm not trying to screech to a halt, I still feel like I'm getting a good workout with the brake. Probably I am spoiled by modern cars, and probably I need to re-bleed the system for the billionth time. But if that doesn't help, I personally would be temped to install hydroboost just so I work less.

 

Perhaps, but have you ever tried to stop a loaded truck with just the reserve pressure in a hydroboost? Doable, but it's liable to cause a pucker mark to be a permanent spot on the seat........

I'm not going to convert right now. I may at some point in the future, if it becomes an issue with keeping a working vacuum pump on the truck. With a cummins, the vacuum and PS pumps are bolted together, and driven by the cam gear. I have a couple spare units at the shop, so it's not like I don't have backups.

 

Tim hasn't tested the cam specifically, but he has in reality. I dubbed my cam "Pantera Jr" as it is the Pantera grind that Tim worked up with Comp, but with less lift. The Pantera grind has a smooth idle, so this should as well. And, the Pantera moniker is because it was designed to give the 335 series engines in the Pantera sports car excellent torque and horsepower.

So, the thought is that if I'm ever going to do it now is the time? Kyle found one in the same salvage on a Lincoln. So, why not get the hydro boost unit and hoses from it? Is there a reason to get one from a pickup?

 

I'd double check the specs on the Lincoln versus pickup boosters, just to make sure the Lincoln's will work. As to why not, I see no reason not to. If your climate control will be all electrical through the relay system you were discussing, then you can run the basic remaining vacuum directly from the carb (advance and PCV) and really clean up the vacuum routing. You can also route all the HB lines over on the DS inner fender cover (I can't recall the exact name for that) and your truck will have a much cleaner look. IMO at least.

 

I don't know where to get the specs for the Lincoln or the pickup boosters. But I could see whether they appear to be the same thing from an auto parts catalog.

As for cleaning things up, I'll still have a vacuum line to the cruise control. So I'm not sure shedding the one hose to the vacuum booster and adding two hydraulic lines will make a huge improvement.

 

I forgot about the cruise. My bad.

 

Stopping a truck with no vacuum boost is no walk in the park either.
A dead engine while in motion is no good in any situation.
Recent GM ignition recalls and the older Ford TFI issue attest to that!

Maybe when everyone goes to electric rack and brake assist there will be an option that can still function with the engine off?

 

My wife's GLK has that setup.