Need answers; hydroboost swap and Eaton disc conv.

[dewdew]

Two questions. I am looking into converting to a hydroboost setup and am trying to find out what vehicle I can steal all of the parts from. I have spent many hours reading old posts, but could not find real specific answers on all parts needed. I would need to replace hydroboost, master cylinder, steering gearbox, and power steering pump, right? I will need a disc/disc master and would like a newer style (aluminum body, plastic reservoir) and possibly a gearbox with a tighter ratio. Is there one vehicle I can use parts from, or could you tell me which vehicles? This would all be going on my '71 C20 Cheyenne. Also, my truck has an Eaton rear axle and I would like to do a rear disc swap. I have read that the 14 bolt brackets will work with the Eaton. Is this correct? Is there any differences at all? Thanks for all your help in advance.

[dewdew]

Ok, so far it sounds like the 14 bolt disc brake brackets will bolt up to my Eaton axle, but the spacing is slightly different. I could not find out how different it was though. The only kit I could find specifically for the Eaton is from Blackbirds, which seems like a nice kit, but I could save a whole lot of money buying the rotors myself. Also, it seems a gearbox out of a '73-'87 has a tighter ratio (one less turn lock to lock) and should bolt up. Is there anyone that could agree or disagree with these findings or give me any more info?

[Yukon Jack]

Here is a post about my hydroboost swap that should help you out with some of your questions.

http://67-72chevytrucks.com/vboard/s...d.php?t=223491

[dewdew]

Thanks Yukon. Is it theoretically possible to use virtually any hydroboost? Obviously I would use one meant for a truck, but couldn't I get one from a newer Chev, that way I could utilize a newer aluminum master cylinder? It seams I will need to do some fabrication either way and lines will probably need to be made. Also, looking into my gearbox situation, I found that the 73 and up gearboxes have a smaller input shaft size (3/4" instead of 13/16".) Is this what people are using and just changing the last section of the steering column to match, or is there something I am missing?

[topdog]

Heres a place that has a rear disc setup for eaton( www.tsmmfg.com)

[dewdew]

Tsmmfg.com only sells it has a kit with rotors just like Blackbirds does. I don't want to pay $300 if I can just get brackets for less than a hundred and buy to rotors for much cheaper myself. Does any one just sell brackets for the Eaton?

[wibilly]

i bought mine off ebay they were listed as 12 bolt brackets fit fine. iwasen't impressed with the spacers, they wern't cut squre but did give the right spacing. next one i do i will just use front brackets and weld them where they need to be.aftermarket bracketsonly suport the calipers on the thickness of the bracket unlike the gm ones. we set up a ford 9" with caddy calipers and cut the store bought brackets to use as templates for front brackets and spring perches it was a much nicer set up and easy to do

[Yukon Jack]

Originally Posted by dewdew

Thanks Yukon. Is it theoretically possible to use virtually any hydroboost? Obviously I would use one meant for a truck, but couldn't I get one from a newer Chev, that way I could utilize a newer aluminum master cylinder? It seams I will need to do some fabrication either way and lines will probably need to be made.

I can't think of any reason you couldn't use a new Chevy's hydroboost system. What made my swap easy was I was using the donor truck's motor and all of the accessories so I did not have to do any modifications to my stock power steering pump. Only think I had to do was swap the old high press steering box flare end onto the hydroboost's high pressure end since the old style is a flare end and the new style had an o-ring end.

[dewdew]

So, I decided to attempt to put a newer style master cylinder for two reasons. First, the setup would cost twice as much, while still netting me the same results. Second, I am starting to think the a aluminum/plastic master cylinder would look out of place on my '71 (unless I was to do a fuel injected motor and a rack and pinion.) I have decided I will probably go with a hydroboost/master cylinder setup off of '92-'93 C/K30 since they had rear disc brakes, and coming off of a one ton I know it will have the stopping ability. I really just need to know what kind of power steering pump I should use and get reassurance that a '73-'87 gearbox will work (and have a quicker ratio.) Any input?

[wibilly]

i would check on the 80s diesel trucks blazers or burbs they used the hydra boosts not sure if those pumps will work with our brackets or not.i also noticed on the 76 eldorodo i got my rear caliper cores from had a hydra boose as well. i just used mt 3/4 ton vacume booster and master with no isues

[cysko9]

i'm gonna try it with a new bosch unit (2009 GMT-900 and DCX-DM). I'm not sure how its going to hook up, but I'll probably try something like Yukon Jack did. Hopefully his templates will give me something good to start off of.

hopefully it comes together.

[billyjo]

I'm using the power steering pump from an 05 Hummer with my original steering box.

Bill

[earl87gta]

The power steering box you have now will work you only need to change it if you feell you need for the closer ratio it also makes the stering lines easyier to get the older box uses diffrent fitting. for the steering pump do a serch on ebay for m1009 m1008 and you will find what you need other then that any k or c 30 with hydro boost will work some help full links for you on the eaton disk swap.

http://67-72chevytrucks.com/vboard/s...d.php?t=247672

http://67-72chevytrucks.com/vboard/s...d.php?t=183452