Thanks Rick, appreciate the input.
I checked the static timing when I installed the dizzy so it *should* be right - once I find my inspection mirror I will double check it.
When i stick a timing light on it, it seems to be sitting at around 16 deg with the vac advance connected at idle - should I try bumping it up to 15/16 at idle without the vac advance?
May have to Macgyver something up to connect it to both ports, as i've got the brake booster connected to one side of the manifold. Might be better off having both the booster and vac advance connected to both.
And I've seen what you mentioned about being all in at 2800 rpm - again, i'll check this with the vac advance disconnected and see if i'm getting 20deg at the same revs.
Just out of curiosity, what are your jet sizes?
MINI66 wrote:
Hey Gambo
I have the same setup (1275 - 45dcoe) running a re-graphed Pulsar dizzy with the following timing.
Mild cam (No vac adv)
1000rpm/idle - 15-16deg adv
2800rpm - 34-35deg adv (all in max advance)
(So around 20deg of mechanical advance in the dizzy)
This works really well in my case.
Shouldn't matter what dizzy as long as your advance curve is right.
Most of the other examples of similar setup that I have seen have all in max advance by about 3500rpm.
My advice would be to try some more idle advance and check the dizzy to confirm that the mechanical advance is working properly. If it starts to ping under load or is very hard to crank you have gone too far.
Also confirm that your timing mark is correct. (Clutch cover inspection hole v's crank pulley v's number 1 at tdc (look down plug hole))
I have also seen DCOE setups running fine with vac advance as long as it is plumbed to both sides of the manifold.
Note that Vac advance is only supposed to come in under cruise/hi vacuum situations, not under load, so the vac signal from the weber or the dizzy setup must be screwed up to give advance under load.
cheers
Rick