CK5
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1973 C10 "The Purple Truck"

Basic build
What I believe that I found out was that the aluminum master cylinder is a "quick take up" design. The lines are swapped front to rear compared to the iron one, but same size when I checked.
You just have to make sure that you have the proper booster bore to do it.

I believe that there was a brake system upgrade from the factory, (JB6???)
I honestly don't remember the RPO code. Seems like it made a difference in single or dual diaphragm booster.

@500$k5 may remember it better, since he researched it years back.

I would dig into what Power Stop may offer, too.
 
Just match the components up, you’ll be good even one piece at a time
 
When i was doing my brakes i came across a few calculators that take the piston area of the caliper, with the bore of the master, and brake pedal leverage ratio..? It will solve for the missing value in terms of how big the bore of your master should be, and for the brake size you are running. Not sure if thatll help, but might let ya know the master you might want, wont work ideal with the brake upgrades of the future or vice versa
 
What I believe that I found out was that the aluminum master cylinder is a "quick take up" design. The lines are swapped front to rear compared to the iron one, but same size when I checked.
You just have to make sure that you have the proper booster bore to do it.

I believe that there was a brake system upgrade from the factory, (JB6???)
I honestly don't remember the RPO code. Seems like it made a difference in single or dual diaphragm booster.

@500$k5 may remember it better, since he researched it years back.

I would dig into what Power Stop may offer, too.
I saw a lot about that JB number for identifying brake package in squarebodies, but my tag lists J70. Looking that up it's the same number used by the 68-72 trucks just signifying power disc brakes. Looking at a booster for a 1972 vs 1973, they are different despite having the same RPO code.

When i was doing my brakes i came across a few calculators that take the piston area of the caliper, with the bore of the master, and brake pedal leverage ratio..? It will solve for the missing value in terms of how big the bore of your master should be, and for the brake size you are running. Not sure if thatll help, but might let ya know the master you might want, wont work ideal with the brake upgrades of the future or vice versa
That might come in handy.
 
Installed the tailpipes today. The primary reason is for the PF4. It runs much better with target idle at 750 RPM but the short exhaust was annoying idling at 750. If I lowered the target idle, it was dying when I put the transmission in gear or even when I turned the AC on. So I needed to make the exhaust tolerable for the higher idle speed.

I found a cheap 3" tailpipe. I think the application was a GMT400. It was $70.

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The downside is it's only available for passenger side exit. I bought 2 and figured I could modify 1.

The passenger side worked perfect. I didn't even need to change the length.

I cut the other tailpipe in 3 places so I could change the orientation.

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It worked so well, the new tailpipe landed right on the factory hangers.

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It's annoying because I couldn't have done it better if I had actually been trying. So if course since I wasn't, it lined up perfect!

I don't think it's too much quieter standing outside the truck, but it definitely helped from inside the cab.


I left the ends how they landed for now. I hadn't put any forethought into what I was going to do. I think I want to put stainless tips on it.

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While I under the truck I finally removed an odd previous owner device that is in the bed.

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I know there was a camper in the bed. I'm thinking this might have been a way to dump the dirty water.
 
I need to start improving the brakes. I'm planning to start with the master cylinder and brake booster. I have some questions I haven't been able to find answers to.

I've found some nice master/booster combos but the list them as "conversions" so I don't know if they will bolt on to a truck that already has power disc brakes.

The other question I have is if I can use a newer master/booster combo. I like the aluminum master with the plastic reservoir because it's easy to see the fluid level. I'm wondering if the pedal connection would work between the 73 pedal and the newer booster. Or would a newer master bolt to the older booster, assuming bore sizes are the same.

I installed an aluminum MS and plastic tank on my 74 and 84. I’ll see if I can find the part numbers.

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Here ya go
Thanks! I actually started reading thru the Sancho thread but didn't see that post!

You're firewall harness gutter looks like mine did. When i pulled the last engine I accidentally finished it off. I tried to order a replacement but the only one I could find was for 67-72. I gave it a try but it's too long and it wasn't big enough to fit all of the wiring.

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I'd still like to find a proper gutter because it very convenient from routing stuff.
 
Just say no to exhaust tips.

Martin
So I was debating how I would cut the ends. I'm leaning towards a compound angle that makes it slanted but also in line with the bedside. Our '08 Silverado has the end cut so the opening essentially points straight back.

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The other question is how far out? Right now, they are definitely too far.
 
Thrush welded. It's 2-1/2" off the headers to an "H" crossover pipe and then expands to 3" into and out of the mufflers.
 
I cut my exhaust kind of like you were saying, I cut it almost parallel with the rear bed side, but also angled back a little at the bottom at the same time...

I think just the plain aluminized exhaust pipe looks fine, tucked in, no shiny tips. But I do like the angle cut.

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