For brake booster pictures, go to
Brake booster post # 8.
In my garage is an A1-Cardone dual/tandem booster p/n 54-73172, still in the box, which I can drag out and take measurements – if wanted. I also have a ’84 Gran Fury booster “loose/removed” as well, for measurements.
One thing to keep in mind is the
power brake booster is mounted about 1½” (going by memory, which may or might not be correct) higher on firewall above the location of
manual brake master cylinder, because of the multiplier linkage (or whatever you might want to call it).
There are three pairs of holes on firewall. The bottom pair of holes (4) are for manual brake master cylinder. The top pair of bolt holes (4) are for the power brake booster.
The tandem “K” booster has a smaller diameter than the single “K” booster is – but (I believe) both will fit with either the B or RB big block version.
The small block driver’s side rear-most valve cover bolt is almost impossible to access (need a wrist that bends in an impossible manner) with the stock booster in place. Trying to install some aftermarket (finned aluminum) valve covers is also impossible (the booster and valve cover wants to occupy the same real estate).
This doesn’t apply to big block cars with either “K” booster (I don’t think – not tried, yet):
I will try to dig out some parts tonight and take better pictures (if I can remember) if wanted.
This is a picture of a early ('76 to '78?, not sure of the year break) FM body from another forum member (Jim in AZ) - which uses cast iron master cylinder.
The top row of holes is hard to see because they are in a shadow, but they are there. I believe your gloss black firewall stiffener plate uses the top and bottom row of holes. The older (cast iron) master cylinders that uses 4 bolts (instead of 2 bolts for aluminum) uses the bottom two rows of holes. See next post for comparison.
These are some big block photos I’ve saved – but not sure whose car they are from:
‘77 Aspen with a 400. From the picture it is using a stock booster with 4-bolt cast iron master cylinder.
Pic 2 of the same.
’78 Road Runner with either a 413 or 440 (both RB, with a stock booster).
’79 RT with 440 (with a stock booster).
I’ve kept other pictures, but it is not clear as to which booster each car is wearing, so I didn’t include them.
It is assumed the engine came in from underneath, when using the stock booster.
If using headers, I would remove/install an engine (either small or big block) from underneath, anyway – for headers suck when installing an engine from above.
BudW
Edit - I missed a detail.