Flush Mounting My Power Brake Booster
 

I could not find any threads on this topic that had any more detail than just a brief paragraph, so I figure I'd pit my experience out there.

I started by determining how much to widen the old master cylinder hole on the firewall, I opened it to about 2 1/8 inch, instead of grinding with a die grinder or carbide bit, I got a Milwuakee hole saw. I took some 1/8 inch flat bar, and made a bracket so I could center the hole saw and hold it steady when drilling.

From there I made a template out of scrap wood, transferred the markings onto the firewall and drilled accordingly.

You can see as well I had to modify the column bracket, I took one of my extras and chopped it up to clock the other bolt hole in a new location, keeping a factory style appearance, and maintaining rigidity for the column.

Going inside the cab, I had to remove a lot of the bracing in this area for the booster mounting holes/flange. I want the firewall to be as strong as before, so I took some of that 1/8 flat bar and welded it into the old brace location, and as you can see I seam sealed and painted it.

Now it is fully flush mounted. The only thing I do not have in here is to drill the old brake pedal assembly bracket, but thats a given. I will more than likely take the old studs to the bracket pedal bracket and reverse them to fill those holes. To accomplish this I may have someone machine me a 1/8 plate to sandwich between booster and firewall, much like the hydroboost setups do.

Once I get to the pushrod setup, I will report back.

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Re: Flush Mounting My Power Brake Booster
 

Inside pix and final assembly pix.

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Re: Flush Mounting My Power Brake Booster
 

That came out nice. Did you do this to make it look neater, or are there some functional benefits as well?

Re: Flush Mounting My Power Brake Booster
 

Nice job, I have a 67 parts truck somebody did a similar thing to but yours is neater. Jim

Re: Flush Mounting My Power Brake Booster
 

I like the neatness of it, I doubt theres much more benefit to it other than less linkage to wear out. Saw it on Nacho truck from Delmo and wanted to go for it.

Re: Flush Mounting My Power Brake Booster
 

I did the same but used a booster from a Chevy Van. It's larger in diameter, but not as deep. I don't think I had to cut the hole larger, but it has been almost 20 years.
The reason i did it, was to get the MC back away from the carb and aftermarket manifold on the inline 292.

Re: Flush Mounting My Power Brake Booster
 

Here's my closer, the pedal pushrod(s);

So after much thought, I decided to utilize the bellcrank assembly on the inside of the cab. I did this by using just the actual pivoting bar the pushrods will attach to, and drilling a hole on the brake assembly, and welding on a 'leg' to the other side, to slide the pin through and hold the pivot bar in place.

When adding the pivot bar where I did, I had to cut the brake pedal assembly to create a relief for the arms to swing full motion at the top, so I took 1/8" flat steel I had and bent a radius into it to reinforce this area. This does not interfere with the return spring when being careful and trimming where needed.

Could I have just used the lower hole for the 4:1 ratio, sure, but I didnt like the angle it produced. This will be cleaner, operate better and have longevity.

I attached the diagram I used to calculate this, as per Wilwoods site: https://shop.wilwood.com/blogs/news/...o%20of%209%3A1.

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Re: Flush Mounting My Power Brake Booster
 

Just realized I forgot to add a photo of how I split the column bracket to clearance the booster. Here it is;

Re: Flush Mounting My Power Brake Booster
 

Glad you came back to post the pic, I missed this thread the first time. Nice work.

Re: Flush Mounting My Power Brake Booster
 

You couldnt have just used a adjustable rod from the pedal to the booster? Hard to tell in the photos if the geometry is wrong for that.
You did some great craftsmanship doing this.

Re: Flush Mounting My Power Brake Booster
 

Thank you. To the best of my knowledge, the linkage is proper. Its achieving two things: ratio and angle. With an adjustable clevis, the angle would be extreme trying to use the correct ratio. This bracket essentially just moves the input upward and corrected.

Re: Flush Mounting My Power Brake Booster
 

Thank you!

Re: Flush Mounting My Power Brake Booster
 

I wasn't meaning what you did was improper in any way. It just looks to me that it could have connected directly without the piviot so I thought I would asked.