I am looking to hook up an vacuum advance on my Powerspark distributor. Can I hook into the manifold vacuum line from the vacuum canister?
Vacuum for distributors needs to come from either the manifold or from one of the carbs, it needs a fluctuating value, the vacuum canister is going to be a constant, not what you want.
Thanks Robin , superb answer.
It helps with my future direction regards
You are going to want to drill a small hole, say 1/16" in the bottom of the hole the arrow is pointing to on the front carb in the picture. Then tap the larger hold to accept a brass nipple. You attach the vacuum line to that nipple.
Perfect! Just the comprehensive info I required. The pic is a big help.
Should be easy to perform?
No NEED to do so. You CAN connect the vacuum advance directly to manifold vacuum.
My V12 runs happily like this.
http://www.pclarkson.plus.com Mr Clarkson explains how to drill the port to give you the required vacuum from yr ZS carb…this is what I did. Also some ZS carbs on later ( mid 70s ) XJ12s had the ports already fully drilled.
How would you do this ?
T into the vacuum feed that goes off to the brakes BEFORE the 1-way valve - if you don’t want to modify the intake manifold. Otherwise, you could install a fitting underneath the intake manifold where it is not easily seen.
Thanks Phillip for your instructions . Much appreciated.Ian