Replacing the 235 with a 261 bought the extra CCs. I’m using a reground 261 cam which provides more lift than the 235. My dual intake will provide ample fuel mix at the top end. Increasing the compression will increase HP across the board and boost economy at the same time. However, my primary interest in compression is to have ample power at lower RPMs for decent acceleration from a stop. At the same time I don't want compression so high that my idle speed will be excessive or make the truck shake and rattle when stopped. I have no desire to go 120 MPH but I would like enough power to cruise up a reasonable hill at 60 MPH without losing speed or downshifting.
My goal with these questions is to determine the maximum compression I can go with to reach my goals with pump gas. After determining the appropriate compression target I need to determine how much to shave off my head to obtain it.
With a fixed load we know that fuel consumption improves with higher octane fuel due to increased power per pound of fuel mix. And, the higher the octane the higher the compression can be. That is why I am asking the economy questions; it might well be possible to pay more for premium, increase compression, gain a reserve power across the board, and actually improve or break even in the all important miles per dollar category.
