CK5
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PLAN B

This build was 2 parts 1 i have a truck I made to pretty to wheel so I'm building an ugly one I can actually enjoy. And 2. My cousin has been trying to join us for blazer bash but his truck wont be ready so we are surprising him with this one
Is hydroboost better/stronger than vacuum boost?

The brakes on this truck hasn't been great ever, seems like they got worse after going 1 ton, then worse after 40s and worse again post ls swap. I keep guessing and replacing parts but I'm wondering if I need to swap to hydroboost. I have hesitated doing that because I didn't want to stress my power steering pump with additional work because of the ram assist.

What do the fine people of the interwebs think?
I am pretty sure hydroboost, is stronger.
I don't know how nice it will play with the ram assist, you have to wait for someone who has that too to respond.
 
Is hydroboost better/stronger than vacuum boost?

The brakes on this truck hasn't been great ever, seems like they got worse after going 1 ton, then worse after 40s and worse again post ls swap. I keep guessing and replacing parts but I'm wondering if I need to swap to hydroboost. I have hesitated doing that because I didn't want to stress my power steering pump with additional work because of the ram assist.

What do the fine people of the interwebs think?
I wonder the same thing but read the first page and had to laugh. The truck has come a long way sense I pulled it up obstacles with open diffs!

You order that 2000 stall converter we talked about in Moab yet?
 
Is hydroboost better/stronger than vacuum boost?

The brakes on this truck hasn't been great ever, seems like they got worse after going 1 ton, then worse after 40s and worse again post ls swap. I keep guessing and replacing parts but I'm wondering if I need to swap to hydroboost. I have hesitated doing that because I didn't want to stress my power steering pump with additional work because of the ram assist.

What do the fine people of the interwebs think?

I've always had vacuum brakes and never felt the need for hydroboost brakes. I've locked up 40's on the street more than once. You might want to consider the dodge calipers up front.
 
Hydrobost is definitely better than vac assist. As far as with the ram assist, I would do a hydroboost application pump and do the mod to the outlet fitting to get more out of it.
I am running a 3/4 ton 10 bolt up front and a 14 bolt out back with 3/4 ton front discs on it and a larger bore 4 wheel disc P30 master. I have factory hydroboost cuz mines a diesel and an unmodified pump. The master cylinder puts out plenty of flow and pressure and I can easily lock up 35s on asphalt. Had to put a rear adjustable prop valve on it and turn it almost all the way off in order to get the rear to not lock up and come around when driving on wet/icy roads.
 
I’m sure hydroboost is stronger otherwise GM wouldn’t have used it on every square body 1 ton however if it was not possible to get good brakes after an axle swap or bigger tires then vacuum brakes would only be on a minority of the trucks you see but that’s simply not the case.

I may have missed it but what is the braided hose coming off the front m/c port doing?

I feel like there’s a problem you haven’t found.
 
I’m sure hydroboost is stronger otherwise GM wouldn’t have used it on every square body 1 ton however if it was not possible to get good brakes after an axle swap or bigger tires then vacuum brakes would only be on a minority of the trucks you see but that’s simply not the case.

I may have missed it but what is the braided hose coming off the front m/c port doing?

I feel like there’s a problem you haven’t found.
That's a line lock for the rears.

I have been told that maybe my cammed 6.0 isn't giving enough vacuum? I have just been looking at the torque app and it's saying 17-19 vacuum which I thought was close to the 350.

My friend has it at his shop and with maximum effort he can only get 1k line pressure at the front calipers and 750 at the rears. We both think that's way low.
 
I've always had vacuum brakes and never felt the need for hydroboost brakes. I've locked up 40's on the street more than once. You might want to consider the dodge calipers up front.
What engine are you running? I wonder if you have more vacuum than me. My cammed big block can lock up my 37s on my other truck. Same exact front calipers and vacuum booster.
 
I wonder the same thing but read the first page and had to laugh. The truck has come a long way sense I pulled it up obstacles with open diffs!

You order that 2000 stall converter we talked about in Moab yet?
We went back through the receipts from the trans build and he gave me a 2200-2400 stall. I just didn't know at the time.
 
I've always had vacuum brakes and never felt the need for hydroboost brakes. I've locked up 40's on the street more than once. You might want to consider the dodge calipers up front.
This kit @skunked ? https://torqmotorsports.com/product/gm-dana-60-kingpin-big-brake-brackets/

My only concern with that is if I only have 1k psi pressure will bigger brakes help? I'm seeing most places calling for 1400-1800psi. Almost all hydroboost kits are claiming 1800psi out of the box.

I will say I would much rather have vacuum vs hydro because I really want to keep the two systems separate... but I'm also sick of missing offramps and fearing driving in traffic because I can't stop in time.
 
This kit @skunked ? https://torqmotorsports.com/product/gm-dana-60-kingpin-big-brake-brackets/

My only concern with that is if I only have 1k psi pressure will bigger brakes help? I'm seeing most places calling for 1400-1800psi. Almost all hydroboost kits are claiming 1800psi out of the box.

I will say I would much rather have vacuum vs hydro because I really want to keep the two systems separate... but I'm also sick of missing offramps and fearing driving in traffic because I can't stop in time.

That’s one of the companies producing brackets. Northwest Fab is another.
 
I've only had hydroboost brakes in my off trucks so I can't give a comparison. They do work great though. Hydroboost does add plumbing complexity and bleeding the power steering system is more complicated.

I got the Vanco high-flow hydroboost back when I had the K5. It was hydroboost due to being a diesel K5. I swapped that hydroboost to the crew cab. I don't remember if there was much of a noticeable difference after getting it.

I installed a PSC steering box after I'd run the crew cab for a while. Again, I wouldn't say it made a huge difference.

All that being said, I never finish a wheeling trip wishing I had a different brake setup. It all works great. I never have a concern making a panic stop on the highway with an 8000lbs truck and 40" tires.
 
For reference I'm factory front brakes and 2003 2500hd twin piston rear on discs. With the disc/disc proportioning valve the fronts did like 90% or more of the braking. Made the truck nose dive like crazy whenever I braked hard.

Installed the factory 91 V2500 suburban master that I noticed burb had. Its advertised as qual piston size front and rear and larger than the factory 86 k5 master. Brakes are miles better. Can lock them up whenever I want and as far as I know I have the original vacuum booster still installed.

The resovoirs are flipped so you just have to swap the lines front to back when installing. Might be worth a shot?

Edit: Found the proportion valve.

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I recently swapped to the master to one from a 99 c3500 with disk/disk and that didn't change anything at all.

We just swapped boosters to a brand new vacuum booster and swapped to a PV4 proportioning valve. No difference at all :(

My mechanic put a vacuum guage on it and said I'm sitting at 15 at idle, I was seeing 17-19 on the torque app. He said 15 should be enough vacuum pressure but I swear I was reading that17 to 22 was common for tbi 350s.

I am thinking I have enough vacuum to work the booster but not well. I think the difference with this build is the LS.

It may be time to really consider hydroboost. Anyone know if all hydroboost squares use the same brake pedal?
 
For reference I'm factory front brakes and 2003 2500hd twin piston rear on discs. With the disc/disc proportioning valve the fronts did like 90% or more of the braking. Made the truck nose dive like crazy whenever I braked hard.

Installed the factory 91 V2500 suburban master that I noticed burb had. Its advertised as qual piston size front and rear and larger than the factory 86 k5 master. Brakes are miles better. Can lock them up whenever I want and as far as I know I have the original vacuum booster still installed.

The resovoirs are flipped so you just have to swap the lines front to back when installing. Might be worth a shot?

Edit: Found the proportion valve.

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What engine do you have?
 
If you think vacuum is the problem get a reservoir from Summit ($40).

Considering all the parts you’ve replaced with no change, I don’t think you’ve found the problem yet so I definitely wouldn’t Hail Mary a hydroboost conversion at it.
 
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