the mounting bracket where it bolts to the firewall on a astro van is angled because the front of the van dives so it has to be a angled unit. with the Rover same thing you need the angled unit to Clear the shock ktower and abs and stuff...
hydroboost brakes on a disco,couldnt stop those big tires
- Thread starter mightymg
- Start date
Yeah thats me and justions friend Eric. we did our hydroboost Close in time, hes my neihbor. Thats where I got the idea..
Anybody know the bore size on a stock 110 master cylinder? I am trying to put together a series II hybrid and am working up the brakes from scratch with an astrovan hydrobooster. The brakes are stock 110 4 piston disc fronts and drum rears. The astrovan has a 1 1/8" master cyl bore; I wanted to keep something similar to the stock rover bore size, figuring that the piston ratio was set up ideally by LR. Unfortunately I don't have a stock LR cylinder to investigate, and I've searched online for specs with no success... :banghead:
On another note, is there an easy way to tell whether my astrovan MC has a rear drum check valve in it? I just assumed at the junkyard that it had drum rears... never checked. Reading this thread it looks like 4 wheel discs were an option. If I throw a unit with no check valve on it on there I'm going to get "sloppy pedal"...
- matt
On another note, is there an easy way to tell whether my astrovan MC has a rear drum check valve in it? I just assumed at the junkyard that it had drum rears... never checked. Reading this thread it looks like 4 wheel discs were an option. If I throw a unit with no check valve on it on there I'm going to get "sloppy pedal"...
- matt
mightymg said:
I know this is an old topic. I am giving it a bump because of doing the conversion to my truck.
In addition to this upgrade I want to add an accumulator (referred to as compression cyl above) with several hundred cc's of capacity. The GM accumulator just screws into the hydroboost unit. So a custom fitting, an HP hose, and an accumulator later I should have 15-20 shots of braking available.
Alternately an accumulator inline with a one-way check valve between the HP (power steering) pump and the steering/braking systems would give reserve for brakes and steering.
Sounds like fun!
Thanks for the pics; they give a very good look at your setup.
Since you are doing this now can you list all parts you purchased I would like to this as well the pics on the tread are good but there is no clear discrbtions of all parts needed
Does anyone have a list of the parts needed for this conversion I would like to make it a turkey day project
The accumulator I am using is a common Citroen part. I have not bought the hydroboost unit yet but am looking at the Chevy C20 version.
Funny to see this thread come back to life.
I actually bought this same conversion from Lane a couple years ago when he parted out the Disco. Install was pretty simple as i kept the ABS in place, but I think I want to remove it.
After running the brakes for a year, I since had to replace the master cylinder. It was tricky to narrow down exactly which one it was, but eventually found it and cost me all of $30. I just needed to swap out the reservoirs as the new one was too big.
There are a couple things to note:
1. The original brake pedal was kept, as Justin welded a new extension the the power booster. This weld broke and luckily I wasn't too far from home! Go with one from the matching vehicle.
2. Remove the ABS. It will give you more room and will be easier to hook up.
3. Go with good lines. Justin spent a few bucks and had universal hydraulic lines built for this. Really nice in case you need to replace it.
4. Not sure if this makes a difference or not, but replace the PS pump and increase the orifice of the output line. Justin did the same but I chose to keep the original. There seemed to be a lack of pressure and I think the GM PS pump puts out a bit more volume/pressure. I had the GM replacement on another disco (and even though some claim there is no difference), I could certainly notice an improvement. I just got a GM and will be replace it this weekend!
I actually bought this same conversion from Lane a couple years ago when he parted out the Disco. Install was pretty simple as i kept the ABS in place, but I think I want to remove it.
After running the brakes for a year, I since had to replace the master cylinder. It was tricky to narrow down exactly which one it was, but eventually found it and cost me all of $30. I just needed to swap out the reservoirs as the new one was too big.
There are a couple things to note:
1. The original brake pedal was kept, as Justin welded a new extension the the power booster. This weld broke and luckily I wasn't too far from home! Go with one from the matching vehicle.
2. Remove the ABS. It will give you more room and will be easier to hook up.
3. Go with good lines. Justin spent a few bucks and had universal hydraulic lines built for this. Really nice in case you need to replace it.
4. Not sure if this makes a difference or not, but replace the PS pump and increase the orifice of the output line. Justin did the same but I chose to keep the original. There seemed to be a lack of pressure and I think the GM PS pump puts out a bit more volume/pressure. I had the GM replacement on another disco (and even though some claim there is no difference), I could certainly notice an improvement. I just got a GM and will be replace it this weekend!
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macro does yours groan when you hit the brakes? I could never get mine to stop doing that, really made the vehicle feel like it was a POS every time I hit the brakes. Tried all kinds of stuff to make it stop.
I went back to regular vacuum boosted brakes a few months after putting hydroboost on, then put defender front calipers on. I'm good with the way it currently stops.
I went back to regular vacuum boosted brakes a few months after putting hydroboost on, then put defender front calipers on. I'm good with the way it currently stops.
robertf said:
Theres not so much a "groan" but it does wine a bit. I'm hopping the altered GM PS pump will fix at least some of that.
I also have the cheap-ass defender front conversion. Its the rotors from the defender, vented, but instead of actual defender calipers, Bill at Great Basin Rovers had a spacer kit I put on.
My wife isn't sold on the conversion. I think its 6's really.
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My hydroboost always groand and whined even with the GM pump. I also went back to the vacuum booster shit, just b/c my booster started leaking and I wanted something a little bit quieter and something that wouldn't leave me stranded if one of the booster lines bursted..
Re: hydroboost brakes Brining it back
So I started installing the system and after reading Marcos post of using the matching pedal assembly. I am now in a bind the pedal assembly from a 87 astro has the pedal all the way to the left and way to far under the dash. Is this common I have no problem cutting and welding the arm of the pedal if need be I just feel like something isn't right HELP
So I started installing the system and after reading Marcos post of using the matching pedal assembly. I am now in a bind the pedal assembly from a 87 astro has the pedal all the way to the left and way to far under the dash. Is this common I have no problem cutting and welding the arm of the pedal if need be I just feel like something isn't right HELP
I took the pedal from the rover and reworked it to fit in the astro van pedal housing now did you have to cut the pedal housing from the astro van to get it to fit under the dash