Using SeaFoam
HOLY CRAP! If you haven't used Seafoam yet, do yourself a favor and run a can through your engine. The reaction you get driving down the road leaving clouds of white smoke in your wake is hilarious. I know I passed other drivers and left them thinking, "That poor guy blew a head gasket in that old car and we'll overtake him sitting on the side of the road, broken down."
On the practical side, it did smooth out the 340. I put half the can in the gas tank, and used a vacuum line to introduce the other 8 oz. into the engine directly. Fun product to use.
