My pop and i restored a 79 lil red express. Working w the machine shop in my dads area we decided to put flattop pistons to make up the difference for the open chambered 360 heads and factory low compression pistons it had, we also put in a 68 340 cam. Truck ran great. Dont recall what the compression ended up at, but the ***** would ping on anything less than 92 octane, and ran like a scalded dog.