Our most effective gasoline fuel additive is Berryman B-12 Chemtool Total Fuel System Clean-Up (part #2616), which will thoroughly clean the fuel jump, fuel lines, carburetor, intake valves, and combustion chambers. If you have a stuck compression ring, then pulling the spark plugs to do a piston/cylinder soak is a great way to tackle that problem. However, performing such a soak with either of our Chem-Dip products (part #0905 or #0996) is not advisable. Instead, use Berryman B-12 Chemtool Fuel System Cleaner (part #0116) for the cylinder soak. If you have a V-configured motor, then it may take nearly a full bottle of 0116 per cylinder to ensure that you cover the entire compression ring, especially if that ring is stuck and allows some of the B-12 Chemtool to migrate toward or into the crankcase. However, if you’re doing all cylinders and don’t mind soaking one side at a time, you may be able to jack up one side of the vehicle to flatten that bank of cylinders a bit and thereby cut the amount of product required. You can also buy Berryman B-12 Chemtool Fuel System Cleaner in a 1-gallon size. That part number is #0101. Good luck!