What are hydroboost brakes?

[GsxrMike]

I got this M1008 for parts and the brake booster has hydrolic line running to it from a pump on the front of the engine. Is this a hydro-boost that I have been hearing about? Would it be worth swapping with my current vacuum booster? If so is there a thread on how to do it? Do I need to swap the whole master cylinder or what? Thanks guys!

 

[K5dreamer]

yup, thats hydroboost. the pump is actually your power steering pump. all diesel's and i think some gas powered trucks (could be wrong about that) had the hydroboost because the engine dosnt produce enough vacuum, (no carb or throttle blades to get in the way, and with turbo's youll have positive manifold pressure).

im not sure what all is involved in the swap. wish i could be more helpful in that regard.

 

[GsxrMike]

Don't know if it matters but I am going to be running 4 wheel disc brakes.

 

[bigblock72]

The other advantage and the main reason that bigger trucks and vans have hydroboost is that it can create a lot more brake pressure than a vacuum booster. 20-50% more in most cases. So ya it's probably worth doing especially since you have everything you need already.

 

[K5dreamer]

i thought they produced more pressure, but wasnt sure and didnt wanna throw out incorrect info, thanks for the confirmation

 

[454k30]

yes my K30 came with hydro boost from the factory. Certainly helps to power the 1-tons brakes on those axles!

 

[Hogback Fabrication]

You should also realize that hydroboost brakes can mess with the steering pressure (and vice versa) and causes significant issues if you plan on running hydro assist.

Hydroboost does provide more braking pressure but its not better in every aspect. You are still relying on the same pump (the pump itself is identical regardless of if it has hydroboost or not) to steer and brake rather than just for steering in a vacuum boosted brake system.

 

[reddog64]

well worth the swap... Plenty of people i ride/run with have done the swap with steering assist and 4 wheel discs.

you need everything you see including the brake pedal assembly!!!

I just swapped one from a 81 One Ton into my 78 K5

 

[CUCV2]

Don't know if it matters but I am going to be running 4 wheel disc brakes.

From what I can tell, the proporting valve (found on the front crossmember) will correct your brake line pressure to each axle.

 

[mrk5]

You should also realize that hydroboost brakes can mess with the steering pressure (and vice versa) and causes significant issues if you plan on running hydro assist.

Hydroboost does provide more braking pressure but its not better in every aspect. You are still relying on the same pump (the pump itself is identical regardless of if it has hydroboost or not) to steer and brake rather than just for steering in a vacuum boosted brake system.

Yep it does suck coming down the trail without power brakes or steering; been there done that - happend to me on Holy Cross just after the stream crossing. It's a good idea to carry a spare pump and run a cooler for sure.

B_to_C and I plan to run 2 pumps with our hydro-assist setups. That way we can run one pump for steering and the other for brakes and loosing a pump will only cause the loss of one power assisted component.

There is also the option of having the hydroboost unit "high-flowed" so that it runs better with hydro-assist and hydroboost all in one system. Some guys can run hydro-assist and hydroboost off one pump and some can't; It seems to be hit or miss.

I'm running 4 wheel disc brakes with my hydroboost setup and it works great. I didn't add an adjustable proportioning valve but again that seems to be a hit or miss thing with different trucks.

 

[Hogback Fabrication]

Yep it does suck coming down the trail without power brakes or steering; been there done that - happend to me on Holy Cross just after the stream crossing. It's a good idea to carry a spare pump and run a cooler for sure.

B_to_C and I plan to run 2 pumps with our hydro-assist setups. That way we can run one pump for steering and the other for brakes and loosing a pump will only cause the loss of one power assisted component.

There is also the option of having the hydroboost unit "high-flowed" so that it runs better with hydro-assist and hydroboost all in one system. Some guys can run hydro-assist and hydroboost off one pump and some can't; It seems to be hit or miss.

I'm running 4 wheel disc brakes with my hydroboost setup and it works great. I didn't add an adjustable proportioning valve but again that seems to be a hit or miss thing with different trucks.

Running two pumps is the real ticket for hydroboost and hydro assist.

Make sure you let everyone know how that works out for you

 

[mrk5]

Hopefully B_to_C will be testing his out next weekend.