I did a little experiment in my 64 a few years ago. I had a radically built 427 BBC, 1000 cfm carb, single plane intake, .660 lift 292/298 degree solid roller cam. Dialed in with a wideband o2 sensor, it got 12 mpg with a tremec tko600 and 3.55 gears in regular driving to and from work, 50 miles a day. In an effort to extract better fuel economy from it I pulled out, swapped the cam for a tiny solid roller, .514/.520 lift, 270 duration, switched the intake to a dual plane GM piece 3933163 as used on the COPO Camaros and such, and a 650 cfm carb, again dialed in with a wideband o2. In the same daily commute, all that gained me was 1 mpg. But I probably gave up 100-150 hp in doing so. After all that, my theory is that the same size cylinder takes the same amount of air and fuel to fill regardless of how radical the engine is. My next move is to build a 283 to drop in and put the big cam/carb setup back on the 427 and drop it into a drag car. I'm hoping that with some modern efficient heads and a mild cam (somewhere around 210@.050) to pull 25 mpg out of the thing. I think a 390 cfm carb will probably be ideal for me. Devin
LOL 31Vicky...but my pal has more money than sense sometimes...and he's the type that cannot let anyone get "ahead" of him, if you know what I mean...so I just let him do this thing and most times it bites him in the butt anyway...!!! R-
That's exactly why you want to show him how you'd actually have more money thru investments of that 3000 than he could ever save on gas and you'd have it faster. In about 5 years you could double that 3k and in 8 yrs he'd just be breaking even. By the time you reach 8 yrs you'd have your 3 back and +/-7 more.
Yes, and larger (naturally aspirated) engines are less efficient, due to parasitic loss from friction, and the inertia of a heavier rotating mass. It is the reason why my 5.0l V8, 4.0l L6 and my buddies 2.0l L4 all have the same horsepower and torque, only he gets 32MPG, in the same weight vehicle (+/- 50lbs.).
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