Don my suggestion would be to use your old dist as is for the time being since $$$ are tight. I'd set your total at ~35 which since you have already set the curve will make your initial come out pretty good like it did on the previous eng. If it's not pinging no damage is being done only that there would be some additional power to be gained if you can advance it more & still have no ping. This way you can experiment with it until you can afford to get a vac adv unit.