Previously I had submitted a post concerning the addition of a Holley Sniper FI unit to my 1964 Dodge Polara 500. The question was asked at to what kind of fuel mileage I was getting with the car. So I decided to start keeping track of it. I knew the speedometer was off substantially so I did a couple of tests to determine the extent of error. The first was a 10 mile test using the odometer of the car and mile markers along the road the other involved a direct comparison between the speedometer and GPS speed. The calculations showed the speedometer was off by 1.23. Here are some of the specifics for the car:
- 3.54 gears, P295/55 -15 ET Street SS tires
- 500 cubic inch stroker (400 block)
- ProComp CNC ported Aluminum heads 325 CC intake runners
- Heads flow 330 cfm intake, 250 cfm exhaust @ 28"
- Harlan Sharpe, roller tip, 1.5 ratio rockers
- 230/236 @ .050", .550" lift Comp Roller Cam
- Torker Intake (Ports opened up to match heads)
- TTI Headers, 1 3/4" Primary, 3" collectors
- 1800 RPM stall, the motor is a torque monster.
- 9-1 Compression
- MSD 6AL box and distributor
- TTI 2 1/2" X-Pipe Exhaust
The tests were done basically driving to work which is a 25 mile trip through rural Nebraska so not much stop and go driving. I tried to maintain 60-65 mph. Here are the results:
1) 4/20/18 9.1 mpg (3 or 4 full throttle blasts)
2) 5/8/18 10.1 mpg (the best grandma driving I could do)
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