G-body Hydroboost

[treed_cutlass]

Hey guys, I have a few questions on the Hydroboost braking systems from Diesel G-bodies.

#1: Does it have an accumulator hiding in there somewhere? (ie. does it work for a few pumps after the engine is shut off? Or do your brakes go dead as soon as you shut the engine off). I've looked at pictures, and it doesn't appear to have one of the external accumulators, but I read somewhere that some units have the accumulator built into the power piston.

#2: Is it a durable booster? (Any known common defects, disadvantages? etc). Any advantages over other systems?

#3: Any idea if a regular gas-engine master cylinder will fit on the booster?

Thanks for any input!

 

[Oldstech]

1981 Olds Supreme 350 Diesel here, Umm I beleive the accum is built in. Yes, you pose to have few emerg. pump, incase engine dies. And I believe a gas master cyl will bolt up. But hope someone anwser this. But is it ok to run with a hydro system. Cuz I would like to go with a Aluminium verision

 

[KrisW]

The accumulator is the metal "can" sticking out from the side of the booster. You have plenty of pumps when it runs out if the engine dies and still you can stop by pressing hard with no booster working at all. Don't worry about that at all.

I think my hydroboost systems (I have more than one) are wonderful. I have never had a booster fail personally, and I think they work better than the vacuum type. They are more expensive to buy so that is why all cars do not run them. Also, you will still have power brakes no matter the cam you run or the amount of vacuum available. That is your main advantage of running it when you have a gas engine. Also, it has more braking assist power than the vacuum system. My 2500HD Silverado truck with a gas engine came with one factory, even though it has a gas engine. It just flat works better.

You can run a different master cylinder if you want. I personally like the aluminum master cylinder from the 81 Cadillac Seville Diesel. It was made on the "X" body platform (like the 70's Chevy Nova and Olds Omega) and it uses the better aluminum version. You need to make sure that you are running the biggest piston size in the master cylinder possible for the best benefit. Go to a self service wrecking yard and pull a few and measure your piston size. I believe the Cadillac one is still the best size and fit.

Good luck!!

 

[Mudweizer]

If you plan on doing a conversion from vacuum assist to hydro boost make sure you get the brake pedal, hook up point is in a different location for the push rod.

 

[1evilregal]

If you plan on doing a conversion from vacuum assist to hydro boost make sure you get the brake pedal, hook up point is in a different location for the push rod.

good info to know!

thanks for the heads up on that mud! 😱

 

[79loserbluebu]

Astro vans came with hydroboost too. Those are pretty plentiful in the junkyards

 

[KrisW]

I guess I did have to re-drill my pedal once to a different size, but mine wasn't in a different spot. Either way, good reminder to watch out for that

 

[FE3X CLONE]

For anyone that wants a nice bolt-on kit, Hydratech Braking makes a G-body hydroboost conversion. I have one on my '87 and its a nice piece. Costs more than a junkyard unit but they are completely gone through and modified to fit the specific vehicle.

I believe the problem with the original G-body diesel hydroboost is that its nowhere nearly as refined as the modern hydroboost systems you'll find on new pickups, Hummer's, Astro's, etc.

Another advantage with the hydroboost is you'll gain more clearance around your valve covers/engine.

 

[treed_cutlass]

The accumulator is the metal "can" sticking out from the side of the booster. You have plenty of pumps when it runs out if the engine dies and still you can stop by pressing hard with no booster working at all. Don't worry about that at all.

I think my hydroboost systems (I have more than one) are wonderful. I have never had a booster fail personally, and I think they work better than the vacuum type. They are more expensive to buy so that is why all cars do not run them. Also, you will still have power brakes no matter the cam you run or the amount of vacuum available. That is your main advantage of running it when you have a gas engine. Also, it has more braking assist power than the vacuum system. My 2500HD Silverado truck with a gas engine came with one factory, even though it has a gas engine. It just flat works better.

You can run a different master cylinder if you want. I personally like the aluminum master cylinder from the 81 Cadillac Seville Diesel. It was made on the "X" body platform (like the 70's Chevy Nova and Olds Omega) and it uses the better aluminum version. You need to make sure that you are running the biggest piston size in the master cylinder possible for the best benefit. Go to a self service wrecking yard and pull a few and measure your piston size. I believe the Cadillac one is still the best size and fit.

Good luck!!

Thanks for the great info.

I knew the metal can was the accumulator, but after i looked up some of the boosters on rockauto, I noticed that the later years of g-body diesel did not have the the can on the side of them. So i was wondering if it was built in or what the deal was?

Anyways, your car is a 1980 with hydroboost, and it has the can on the side? Are you running the aluminum Cadillac Seville master cylinder on the stock booster? If so do you have a part # on that master cylinder?

 

[Mudweizer]

Check this out: http://www.turbobuick.com/forums/brakes ... stion.html

Junkyard list: http://www.turbobuick.com/forums/junkya ... -list.html