Right, the Magnum combustion chamber is much better than the LA. That is why the 360 style Magnum heads, on the 318 block, with improved intake and exhaust can make real usable daily driver power. So the 360 Magnum heads, with Keith Black pistons which flush out to the deck, raise the 318 compression ration near to 10:1, even better than the 360 Magnum. The stock 318 block, even in the 5.2 Magnum has the pistons max stroke height in the bore below the deck. By using pistons flush to the deck at TDC the real gains of the swirl effect in the Magnum heads help make the power. Team that up with an Edlebrock air gap intake and long tube headers and it makes for a strong every engine that is still reasonable to live with in a daily driver.

I'm getting lazy, and even though I like the manual trans in my 2001 Dakota, I want to set up my 56 with an automatic so my wife can drive it. Part of the deal of me spending the bucks to build this truck is so she can drive it and enjoy it also. When I retire June of 2024 I'll turn in my company car and then a nice pickup truck will be my daily driver. But I cannot justify spending $35,000+ for a used current truck when I can build a great vintage daily driver for less than $20,000. So with some careful choices, a 5-spd or 6-spd automatic with a .67 to 1 or even .62 to 1 overdrive with torque converter lock up can be very efficient on the highway. Again, torque in the 2000 to 4000 rpm range helps so the tranny isn't trying to shift around to maintain the speed I set on the cruise control.