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Discussion Starter #1 (Edited)
Hydroboost was something I was always on the fence about. I've driven some cars with hydro boost and loved it and have also driven cars with them and wasn't impressed. I was never happy with the pedal feel of the b body though compared to newer cars I have driven so I knew I wanted to make sure my 96 felt the way I wanted.

I really wanted to stick with a vacuum boost as I figured my Kore 3 front and rear big brake kit with C6 calipers and stainless flex hoses would give me the stopping power and pedal feel I wanted, but I ran into a big issue with running my fuel lines. There was a specific way I wanted to route them to keep them away from the headers and steering linkage, and I didn't have the room with the vacuum booster. I spoke with CPP and was pretty impressed with the price. They quoted me at just around $700 shipped for the hydroboost, a new slick looking black CPP master cylinder and the hose kit. Considering I wanted to buy a new booster and master and I still had to make custom PS hoses for my LS/Delphi 670 swap, the whole setup set me back about $400 more than going with the factory stuff.

Van from CPP was great to work with and so far the installation has been going very smoothly. I had to mark and drill out the booster for the Impala's bolt pattern (very easy, just hold the booster up to the old gasket outline on your firewall where the vacuum booster sat, have a friend go inside the car and mark the bolt holes with marker through the firewall and then drill 4 holes through the billet aluminum mounting block).

The high pressure hoses were extremely easy to build and the instructions for them were great. Only thing not mentioned is they obviously have to be clocked, and there isn't a mention on how to do this. The way Van recommended to me was to screw the male end of the fitting all the way into the female end , back it out 1.5 turns (without the hose attached of course) and observe the gap (I used a feeler gauge). When you tighten the fittings, tighten it to that point and then finish tightening to your desired clocking position. This will make sure that the male fitting isn't screwed out further than 1.5 turns from tight, and this should be sufficient for sealing the hose to the fitting.

Only thing left that I have to do is build the return hoses but I can't do that until I get my radiator in so I can see where I'd like to mount the remote reservoir.

A good remote PS reservoir is recommended for a few reasons. First, a good one like the PSC one I purchased gives you two return ports with baffling separating the ports so you don't have to Y your steering box and hydro boostreturn ports together. This is a good idea because the two return ports flowing into each other could cause turbulence and create issues with pedal/PS feel. It also increases your fluid capacity over a pump mounted reservoir giving the system better resistance to overheating of fluid. there is also an integrated internal filter (the CPP kit provides an inline filter, but Van said there is no harm in using both).

The only other thing I have to do, other than the return lines, is to drill the brake pedal to mount the hydro boost linkage. The instructions look pretty straight forward though so I'm not expecting that to be difficult.

As far as brake lines go, I built my own custom proportioning valve lines to delete the ABS (along with my own lines for the rest of the car using NICOPP tube and stainless fittings), but I built them using the factory master/booster and they still worked fine. This means on a factory setup, everything below the proportioning valve should be OK as the prop valve isn't moved any significant amount. I did have to bend up two new lines from the master to the proportioning valve because the master I went with used inverted flare instead of DIN bubble flares at the ports.


Basically, my brake system consists of the following now:

Kore 3 325mm front with the optional DBA 067SL/SR rotors and C6 calipers/Hawk HPS pads
Bill Harper's rear big brake kit with C6 calipers and 330mm Stoptech slotted rotors
Stainless flex hose
CPP hydroboost/CPP master
Pro Forged stealth bolt kit


I'm a little worried, especially with the hydro boost, that I'm going to have too much stopping power in the rear due to having larger brakes than the front. The stealth bolt kit should help, but obviously I shouldn't have larger brakes out rear than up front. I did this because I figured I'd have to go to 18's at some point because the production of 335/35/17's has been dwindling and I would want to swap over to 345/35/18 on a 12.5" wheel. If I did that, I'd love to upgrade to the Z06 355mm front brake kit and then the rears would be perfect in proportion. Don't know if the swap to 18's will ever happen though so going with the larger rear brakes was probably a mistake. If this creates a problem then an adjustable proportioning valve is in my future.

FE7DE91F-D889-4569-AEF8-01B9F5CB2A8B by Kris A, on Flickr

AEAC75EA-BEE1-49EC-A6B0-DFC2F5693DA2 by Kris A, on Flickr

CFEAF925-C49B-4311-A259-E42F86E9CF35 by Kris A, on Flickr
 

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Discussion Starter #2

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I see that you mounted your Hydroboost inverted. I did a much cheaper installation with the booster from a 94 Astro van donor.The mount fits the B body perfectly. I "Y"ed my return line, and used one line from an 80s diesel, and had the other customized. It has swivel links at both ends to facilitate avoiding some close passes to the Headers on my 454. I also put insulation on anything that comes anywhere close to the headers.

My booster is on right side up. I have no issues with the "Y"ed return, and brakes and steering work as they should. I had to use the smaller master cylinder from the Astro van, but it still has excellent brakes. My trans needed some work recently, and the mechanic said it has really good brakes. I had to make new lines from the master to the proportioning valve, but if I had sourced my Hydroboost from an 07 or 08 Tahoe (and similar), I could have used my original master cylinder, and I would have only had to change the plate on the Hydroboost with the one from the Astro van (also available on ebay for $25, but you need a special socket for another $46). I welded the eye from the vacuum assist to the Hydroboost on center at 6 3/8 inches from the mounting plate surface for a perfect match with my brake pedal (it is necessary for the Tahoe unit too). My entire cost, including the socket, was about $225, and some time to make lines, and eye to fit. I also get to keep the special socket if I ever need it again.
 

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I didn't know that a hydroboost could be mounted upside down. Guess I can't think of any reason that it couldn't, just never thought about it. Sure would make some of the line routing much easier!

I put the 2012 hydroboost from the donor vehicle on my 96 RMW and used the 96 master cylinder, but had to turn down the pilot to fit in the 2012 hydroboost as it was too big. Otherwise it more/less fit right in. I don't recall if I had to drill the firewall or not (don't think so).

I've put hydroboost in a few vehicles over the years and really like how it works versus vacuum brakes, not to mention all the room it clears up on the firewall.
 

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The Astrovan has a flat mounting plate with the 4 holes appropriately spaced to attach it to the B-body firewall with no modification. I ended up buying a mounting plate on ebay, because all of the Hydroboost units in the junk yard Astrovans were gone. I did find one with the flat plate later, and picked it as a spare.

You need 15 inches of vacuum to operate the vacuum assist for the brakes. I have 10 inches of vacuum, so I had the choice of a vacuum pump or Hydroboost. I tried a vacuum pump, and it worked, but took up a lot of precious real estate under the hood, and was annoying because it ran more than I liked. It looked like crap too.
 
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