230 flathead with Vacuum ignition advance

[Jason Mills]

At present I have a slant six distributor body, converted to fit the flathead, which allows the electronic ignition parts to be used. Mechanical advance only at this time.

I am wanting to add a vacuum advance option to the mix in an attempt to gain the improvements in drivability that it can provide under light loads.

Has anyone done this with the slant six distributor?

I realize Tom Langdon has such for sale ( I do not believe it is a slant six distributor) on the stove bolt website, and some people have converted the HEI to fit the flathead. 15 years ago when I converted to electronic ignition I was happy just to notice the improvements that the captive discharge ignition provided.

At present I am looking for options to improve on what I have. Any and all suggestions are welcome.

[Daryl in Oz]

How to

I've found it reasonably easy to adapt the vacuum pot advance fittings from the bosch type distributors. First you need to figure out where exactly you want to have the vacuum pot, then drill and file to shape the hole for the actuating arm, next drill and tap the small mounting screw holes, don't over-tighten the screws. The final couple of bits are attaching the actuating arm to the movable plate in the distributor, I machined up a stepped stud for this and drilled and tapped the plate, then connect the vacuum line from a port above the carb butterfly. You set your timing with the vacuum disconnected and when you are happy with it you connect the vacuum. To get the best out of it, ideally you should get the distributor strobed (by a specialist) and the advance curve adjusted to suit the application, but unless it's a really high performance engine you should be fine, you may just have to tweak the timing a bit.

[Jason Mills]

Thanks Daryl,

I appreciate your suggestions and knowing it has been done gives me confidence that I could do the same. I will look into finding a bosch vacuum advance canister and go from there.

[Matthew Welcher PWA]

I've found it reasonably easy to adapt the vacuum pot advance fittings from the bosch type distributors. First you need to figure out where exactly you want to have the vacuum pot, then drill and file to shape the hole for the actuating arm, next drill and tap the small mounting screw holes, don't over-tighten the screws. The final couple of bits are attaching the actuating arm to the movable plate in the distributor, I machined up a stepped stud for this and drilled and tapped the plate, then connect the vacuum line from a port above the carb butterfly. You set your timing with the vacuum disconnected and when you are happy with it you connect the vacuum. To get the best out of it, ideally you should get the distributor strobed (by a specialist) and the advance curve adjusted to suit the application, but unless it's a really high performance engine you should be fine, you may just have to tweak the timing a bit.

Do you have pictures of one of these you have done? I would like to see it if you have them.
Thanks Matthew