Question about vacuum tube size

[gm5150]

When converting to vacuum brake setup and using the TTA aluminum vacuum block.
What size vacuum line do I need?
I will be using a 1987 Buick Cardone 50-1243 booster with master cylinder.
I just am not sure what size vacuum tube I need.

Also, does anyone know the GM gasket # number that goes between the firewall and the booster?

 

[mikestertwo]

The standard size is 11/32" but you can get away with 3/8. Make sure you use a hose with a reinforced wall so it doesn't collapse under vacuum. Fuel injection hose will work or find the stock style thick wall 11/32" hose

 

[gm5150]

thank you.
wouldn't happen to know the firewall gasket number would you?