What are most people putting into their 73-87 C10 or something similar? I was thinking about an LS1 5.7 into my 83 C10 that has a 305 in it.

I've owned a 98 Z28 and an 05 GTO so Im familiar with the LS1 and LS2, but not too much with the truck LS series engines.

I ask bc I see more 5.3 and 6.0 swaps. Is it that these engines are coming from trucks so your putting them into trucks?

So I guess Im asking what is the best combo for some power with fuel economy and what kinda fuel mileage would I be looking at on average?