Good afternoon everyone
I have my 1970 Cuda, 383, 4 speed, 4:10 gear. Tires in the rear are 275/60/15.
The engine is bone stock 383 2bbl engine (now factory 4bbl intake, hp exhaust manifolds). I topped it off with a fresh rebuilt Holley 3310-1 780 cfm carb. The carb was tuned by my buddy who actually knows what to do.
The car start half a crank and usually runs good. Every once in awhile on take off the car starts bucking but clears out. The issue I'm having is sometimes it seems like it has bogs when the secondary open and horrible gas mileage. I recently took a 67 mile trip with a full tank and it's now at a quarter of a tank. I did the math and it's getting 5 mpg on side road drives just putting along.
I understand these cars are not built for gas mileage but dang.
Is the carb too much for this engine? Timing is 12 degrees advanced and spot on.
With a 4:10 gear on the highway, it might be nice to know how fast, or what rpm the motor was running on that highway. Then are you running a steady speed, or do you keep hitting the throttle to hear the 4bbl sing? Next, determining gas mileage based on what the gas gauge reads really means nothing. We don't know how full it really was to start with, or how level the car is while you are looking at the gas gauge trying to guess how much gas it actually used.
