Quote:

Rich a question on the stacks needing timing: The old Hilborn constant flow system didn't have timed injection with stacks. Why the difference with EFI?



Because virtually ALL stack systems were mechanical running alcohol. Alcohol is very forgiving of overly rich conditions and the rich fuel mixture is harder to fire making any pop back minimal. And this happens only at a lower street idle. Step up the idle RPM and it goes away. Finally most stack systems were not for street use, so you tolerated the idiosyncrasies to get the look and the HP.

Nothing but horror stories from people that tried to get a mechanical stack system switched over to gasoline.