CK5
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79' GMC C15 - Spruce Caboose

79 GMC 1500
Did gm just put the sheet metal brace in all doors, even ones without sport mirrors maybe?
 
im thinking the sheet metal braces the top hole to the inside door structure, and the rod style brace supports the bottom mirror hole to the inside door structure? Im sure the depths of interweb will let me know eventually.
 
I got the seats fitted in the truck. Spent a bunch of time making sure the brackets were level and all that... Just to fight them anyway because I didn't take some things into consideration.. Since they don't recline, they sit way to flat for my liking. So I took the two front bolts out and reclined until it felt good. Stuck my fingers under and got a decent guesstimate... Two fingers worth of gap.

Made a new template for the front brackets that will bolt the seat, to the slider


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once I have the seats at a finished height, I'll try and make some console brackets to finish up the interior work. After the interior is figured out, next step is door guts..
 
I also ordered up somg Gm jacknuts for the windows, and a corvette style disk/ disk MC. Its got a 1 1/8 bore so it should be good with the brake booster.. I havent even driven this thing and the MC resevoire i got is already leaky, and annoying ( just like the original ). I Am toying with the idea of going back to manual brakes for a cleaner engine bay, and for ease of diagnosing the soft pedal.. Will bleed the whole system again when i install the new master and see what my results are. Was also wondering if the pushrod length will need to be configured from manual brakes to power?

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I installed a disk disk prop valve and had the back brakes dragging a bit before, while testing. When i was researching this, i came up with some info that said the rear resevoir has an anti flow back valve to help keep the rear brake cylinders full of fluid. I could have just taken it out of the master cylinder rear resevoire, but since it leaks and annoys me... i figured id toss on a proper disk / disk one. I do plan on upgrading the brakes to some big brake kits in the future but no reason to drop 500 bucks on a wilwood master at this point...

What is the prop vlave ratio for disk brakes? I would think it would be the same as the disk / drum set up? Dont you always want more brakes in the front than rear, regardless of what braking system you have?
 
You especially want less braking in the rear of a pickup because the rear is lighter. Some rear brake setups I've seen have a proportioning valve in the rear that will adjust based on how much the rear suspension is compressed. Personally I've never messed with the prop valves in the rear disc brake swaps I've done.

I'm not sure about push rod lengths, but aren't manual brake pedals different. I thought the length of the pedal either above or below the pivot was different so there was more mechanical advantage with manual brakes.
 
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Some rear brake setups I've seen have a proportioning valve in the rear that will adjust based on how much the rear suspension is compressed.
GM issued a service bulletin to remove and bypass those valves as they were prone to failure and didn't work properly to begin with.
 
GM issued a service bulletin to remove and bypass those valves as they were prone to failure and didn't work properly to begin with.
I guess I've been following the TSB without even knowing it because I've always ended up removing them.
 
GM issued a service bulletin to remove and bypass those valves as they were prone to failure and didn't work properly to begin with.
I never knew that, but I had problems with it before and I just bypassed it.
I never thought of looking up service bulletins.
 
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Can I just pull the guts out and use the block to hook up all the lines? I'm gonna look into that
 
You especially want less braking in the rear of a pickup because the rear is lighter. Some rear brake setups I've seen have a proportioning valve in the rear that will adjust based on how much the rear suspension is compressed. Personally I've never messed with the prop valves in the rear disc brake swaps I've done.

I'm not sure about push rod lengths, but aren't manual brake pedals different. I thought the length of the pedal either above or below the pivot was different so there was more mechanical advantage with manual brakes.


Hmmm maybe I have too much mechanical advantage from where it's pinned. I'll look into that also , thanks!
 
Can I just pull the guts out and use the block to hook up all the lines? I'm gonna look into that
I believe that I remember seeing that you just have to pull the rubber check valve out of the rear port. Unscrew the large nut after disconnecting the brake line.
Verify that, it's been a few years since I looked into it.
 
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I believe that I remember seeing that you just have to pull the rubber check valve out of the rear port. Unscrew the large nut after disconnecting the brake line.
Verify that, it's been a few years since I looked into it.

deadly, thanks.
 
Round two seat brackets.. Also toying with a grey console to add some division with all the black interior. grey is just a first coat of primer but i have some grey paint also.
The seat warmers should be here by this weekend so i hope to get the interior finished.

I also did some diggin, and it appears some gm pedals have two holes for leverage ratios. Hoping mine does since power brakes were a thing in 79, if not ill drill one lower down.




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Those seat brackets are looking a bit on the flimsy side. What gauge are you using?


Yea I was wondering about that. Not sure of the gauge but will check next time I'm in the shop. I do have some thicker flat stock laying around. Worst case this will be good RND steel for a template. I'm pretty sure it's 14g
 
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The factory brackets are probably similar thickness but the stamped shape makes them stronger than the flat plate you can make in a vice. I would use 11 ga if possible.
 
Ive been trying to spend an hour or two after work, on the truck everyday to get some progress during the weeks. Today i made another bracket, the existing trial one read .0673" which is around 15 gauge. The piece of flatstock i had laying around is 7/64ths or .1046. I stood on the thinner bracket, and i can see it should be a bit thicker. This one is much sturdier.


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Also no luck on the two holes in the brake pedal. Does anyone have two holes in their pedal and knows the distance from what i think is 7:1 over to 6:1 , for the power brake set up. I could always take the pedal out and do some maths...


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The factory brackets are probably similar thickness but the stamped shape makes them stronger than the flat plate you can make in a vice. I would use 11 ga if possible.

Thats make perfect sense. I dont even have one to go off of. Im realizing the few photos i had originally seen, were not the ones i needed to make.
 
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