I have a Carter mechanical fuel pump on the 428 CJ in my 59, the pump is a copy of a factory 428 CJ pump. It has been on for 6 1/2 years now, and has always worked perfectly. Here in Canada, all of our pump gas has "up to 10% Ethanol " in it. I drive my 59 about 1500 miles a year, and it sits all winter in the garage, from mid November until around April, once all the snow and road salt has disappeared. When I park the car for winter, I fill the tank, and add Stabil and I always use some Lucas Ethanol Fuel Conditioner with every tank.