OK, I've never used a holley 4150/4160 but I will tell you what I do know. My friend bought a new Edelbrock (carter style) carb and could not get it to work like it should on his 350. I do like the Quadrajets. They are usually the best compramise you can get for good performance and fuel milage. I decided to buy a new Holley model 4175 for my Nova. It was a spreadbore style that worked great right out of the box. Ran a bit rich but no big deal. The electric choke was amazing. One pump, turn the key and drive away. It was like I had fuel injection. I bought this style because I thought it would give me half decent fuel milage. Wrong! After a few years I decided another upgrade was in order and this time I picked up a used Speed Demon 650 vaccuum secondary and electric choke that was like new. I've only driven the car once with this carb on it and this is definately the carb I'm going to stick with. It seemed to pull alot harder than with the Holley.
