Vacuum Brake Conversion

63 Coupe

New Member
Got a couple of questions that I'm sure a lot of you know the answer to. When doing a vacuum conversion on an 87 GN, which vac. booster works the best, the single diaphragm or the dual diaphragm? I'm pretty sure both will stop equally well, I'm just wondering if there pros and cons to either one? Also, can the turbo brake pedal be modified simply like just drilling a hole or should I just get one out of a NA g body? Thanks in advance for any input you can share. HS
There is no performance difference between the single and dual BUT the size of the booster may make a choice for you. I used a cordone reman that is the same for the TTA and Buick regal. The drilling and pin installation can work BUT you must get the hole perpendicular to the pedal or it will create a problem for you. Junkyards have pedals here at $5 or $15 if they remove.
I've got a G-body booster in the for sale section

Sorry for the thread hijack, but I have a single diaphragm booster for a g-body for sale in the parts section, in good condition, if you're thinking about piecing together a conversion. I'm happy to take an offer if it works for you.
John A, Turbohh
You not only have to drill a hole you have to put the peg in it.

Everything is always easy with duct tape and a hammer on the internet. :p

Get a used N/A one with the pivot secured in the proper place. :smile:
I pulled a single diaphragm booster from an 1980 Monte Carlo. It is so narrow it pulls the Master Cylinder back a little. Helps a little for changing plugs on the drivers side.

Getting all the wiring for the relays tucked under the larger diameter booster that nearly hugs the fire wall was a little tough.

Like it a lot better than the longer smaller diameter boosters that came on mid 1980 Regals