Rear Brake Conversion Advice

[Jeff Kleiner]

Morning Norm
The one in the car is 38 years old from a donor. Looking closely it’s been wire wheeled and repainted, my guess is several times by the look. Looking closely it has painted over rust all the way around the seam of the body and at the plunger. While I have the car apart, with my luck, I will get it back together and it’ll fail so makes sense, even for piece of mind, to replace it.
Once again it’s good that I have dove in this deep. The 3/4” tube that was coped around the booster, while the geometry is nicely done IMO, the welds are all cold lapped and have cracked as a result so I’ll have to get in there and fix it once I get the booster out.
I do like the Whitby mod assy however.

Actually the tubing mod looks OK; it's not a highly stressed tube. If you're inclined to change it it can be done much more simply by using a piece of 3/4" square tubing beside the existing tube to bridge the cut out portion. I bolt them in with key stock driven inside the tubes so that they don't crush but you could certainly weld it. Here's a couple of pics.





When you get into yours check to see if the booster is mounted directly up against the front wall of the footbox or if it is spaced forward away from it. The donor Mustangs have a double firewall so to keep the pedal and booster in the same relationship when used in our cars the booster had to be spaced forward off of the front wall approximately 3/8". If this isn't done it creates fitment issues and also the pedal will be high when at rest and may even contact the square tubing under the steering shaft. Mike Everson offers a machined spacer however I go cheap and easy by using flange nuts on the studs so that their flat faces rearward. I also use a piece of memory foam around the booster "snout" to seal off the hole.



Cheers,
Jeff