I have a buick 455 in a 67 Chevelle. Not really sure what type of buick it came from or even the year. The carburetor has a spacer. Any ideas on what type of carburetor would be best for this engine, possibly without a spacer. The car came with a holley 650 with no choke flap, double pumper. I need to replace it. I have already tried 2 4bbl, rochester carbs.....also having a difficult time with the accelorator cable and gas pedal.....any suggestions would be appreciated.

The 455 Buick came with a 800 CFM Rochester Q- jet, and for most usages is the best choice. There are many street driven Buicks in the low 12s with this carb.

I agree with the old guy. Buick built them right the first time! Should you want to try to improve things, Edelbrock does an 850 performance Qjet, or if you have a manual box and want the benefits (and the fuel costs) of a double pumper, search long and hard and you will find an 800 Holley model 4011 double pumper. These are rarer than hens teeth however, and you really will have to search. Keep it easy, and go to rochester!!
Best of luck
Malc