Holdfast

Has anyone tried hooking up vacuum advance on the dizzy to ported vacuum with 10 degree split timing. I have a mikuni 44 on a street port 4 port 13b. I hooked up the vacuum advance to the ports where the oil metering lines used to go. That's before the throttle valves(Ported vacuum). It runs really good at low rpm .I only have the trailing set at stock 20° then I tried 15° it was better but scared to go to 10°. I usually run a 10° with no vacuum advance. 6 66uū Haven't really floored it or went on the freeway. Dont want to f it up. But drives a lot better at low rpms.