Which vacuum booster to use?

[SCD]

My third powermaster is starting to fail and I am going to convert to vacuum brakes. Which g body brake booster should I use, the 9" dual diaphragm or the 10 3\4" single one.
Will both of these fit my 87 GN.
If they both fit, which one looks the best installed.

I am going to send the old powermaster back to Autozone to get rebuilt and then store it away.

Any input will be appreciated.

Steve

 

[MG8T7GN]

I used one from an 86 Olds Cutlass dual diaphragm.

 

[mikestertwo]

You want to use the 9" dual diaphram

 

[GNVYUS 1]

Make it easy on yourself, the 1987 Regal 3.8 came with vacuum brakes, then you need this brake pedal and you're set.

 

[dpasadena]

booster

I bought a master cylinder/booster combo for a 1987 na 3.8 regal from autozone and just modified my original pedal. It was pretty easy and the brakes work great

 

[Roger]

84 & 85 Hydroboost doesn't need vacuum. Easy upgrade for 86 & 87.