I have a '55 Chevy 210 sedan with a 350 engine. The engine is a GM ZZ4 Crate engine with a twin pump Holly 750. When I bought the engine the car ran great but I noticed that it always ran on rich fuel. I took it to a local speed shop for tuning and my mechanic told me I was wasting fuel and that 750 was too much for my engine. I wasted fuel and energy. He told me to buy this carburetor from Quick Fuel and he could make the engine run much better. I asked him to carry it today and when I picked it up he was driving my car. When he came back he was smiling from ear to ear! He told me that of all the hot rods he had driven (and there were many), my car was one of the best. He told me the Quick Fuel Carb worked so well that the car just smoked tires when he hit the gas pedal. He said it was very impressive. I drove it home with it and he was right, the car is very different with this carb! The engine sounds and runs much better with this carburetor! I'm very impressed with the performance and looks. The exhaust isn't as fat as the 750. My mileage should improve significantly now. I can't wait to take him for a striptease to see what he can do!