Chris, and that would be an imperial gallon, correct??? That’s got to put you down around 13 mpg (US). Yet, that is still quite amazing for a 1-ton with a 5.13 gear running dual carbs.
The best I’ve ever gotten with my stock ’50, 3600, 216 with a 4.10 and stock sized tires is 13-14 mpg (US). Wish I know your tuner.
Gear ratio? In my experience that always makes a difference, It’s simply a matter of rpm turned per miles traveled.
More cam? Valves open longer therefore more time for fuel and air to be pulled in, result, more power which equals poorer mileage.
Paul I to find it hard to believe that a 235 would run for very long pouring that much fuel through it and still not have the plugs fouled out within a few miles. Lets just apply a little common sense here, an Indy car engine averages 650 to 800hp and is pulling a 1550lb car around a track at an average of between 170 and 230mph. It will burn just under 2 gallons (US) of methanol, a little better on ethanol and where they running gasoline that figure would be somewhere between 3 to 4 mpg. A NASCAR operates in about the same horsepower range on gasoline but has to pull nearly twice the weight, 3400lbs., however they are running at average speeds of 100 to 200mph, their mileage is about 4mpg. Now does it make sense that our 216 pumping out 80hp and pulling 3300 to 4100lbs. at 40mph is going burn 4gallons per mile?
Stu, I’ve experimented with advancing my stock 216 so far that the starter would not even turn it over with out kicking back and the idle was so rough that I thought the engine was going to break a mount and it still would not ping out on the road with 87octain E10 when it was lugged down in forth gear. That’s with stock compression by the way.
Well in the time that it has taken me to research all this, the tone of this thread has changed a bit. Now I see we have over drive with a 3.73 gear, which makes it all the more unbelievable. Paul a rough guess from my end would be that you haven’t sampled enough fill ups to get a real average. There is just no way that your getting that sort of mileage with that set up.
Denny Graham
Sandwich, IL
