JB7 Conversion?

[btolenti]

Anyone know if a JB7 master will bolt onto a stock K5 power booster? I have seen posts saying yes, it will bolt right on, and no, it will require the JB7 booster.

My master has a small leak, so it needs to be replaced, so I figured if I could upgrade....I should.....

I have an 86 K-5, and was considering a master from a 86 K20 with JB7 brakes... From what I can tell, the difference, if any is booster pushrod length, but like I said, some have posted that the 3/4 ton master swap is a bolt on deal....

 

[muddybuddy]

jb7 should bolt right up, jb8 wont (hydroboost)

 

[Jonny-K5]

is there any increase in stopping power going to the 3/4t master on 1/2 brakes? or is it just a "this will also fit" kinda deal. i could see it helping maybe if you've done a 3/4t or 1t axle conversion, but what about an otherwise stock truck?

 

[79k20350]

everything that ive read say the master has a bigger borer and wont fit...