engine cutting out down track after in 3rd gear!

Ok question guys... will the vac advance work at WOT? Reason I'm asking is bc when I raced it I only had 14 deg at idle. And when I pulled my vac hose off the dizzy it was only pulling 20 max with the limiters I had in it. I think I was going all the way down the track with only 20 deg timing.