hello all, looking for some informed opinions on a debate that is going on between me and others about my 1967 f-100. would the truck get better economy/drivability with a mildly built big block running fuel injection or would it be better to build a stout small block with fuel injection. my thought is that due to the trucks heavy weight the big block built mildly (cam, pistons, head massaging,headers/exaust) verses building a stout small block to compete with the big blocks power output in its milder form would actually net better milage and reliability? by big block i mean early 70's 429 or 460 for the big block and 5. something for the small block both running efi and c-6 tranny
Without a power-adder an engine will only consume so much air/fuel. The bigger the engine is, the more air & fuel it needs. Everything else is a variable, i.e.; compression ratio, head flow rates, chamber volume, valve sizes, bore, stroke, intake type, etc. The trick is to make them efficient. The more efficient the motor is the lower the operating cost. If you're looking for fuel milage go with a well thoughtout small block.
cookmatt67:I have to say years ago the Horse Power/Mass was the way to go. Today with the technology we have. Your right! To a Point... I proved this to my son. He has a 1986 Monte Carlo SS 305HO. 2004R trans and a 3:73 posi Rear Gear. He wanted to rebuild his 305. I said a 260/350 Crate engine. But my gas mileage will get Chitty! I bet him the cost of the engine I was right. I even through a bigger Cam in. Well guess who? He went from 19-20MPG to 24MPG. Probably an extra 100 HP and atleast 60Ft-lbs of torque. I don't know if I would build a 460 and say it will get better MPG. A 351 and a nice torquey cam with the rest of the goodies, O/D units today will take a 1000 Horse Power easy. Then you can install a 3:50-3:90 rear gear. O/D units have ratio's to .050 for every revolution the engine makes the driveshaft puts out half. You need the package to work together...Bob