To Much Timing on Low Compression Engine?

I had a Chevy tool truck packed probably 12000 lbs 350 motor, this was back in the early 80's slapped a motor together out of a bunch of used parts the heads were later model with bigger chambers and it really killed the powers so I just kept turning up the timing, it liked 50 degrees so that were it stayed. Ran great up and down hills in the Ohio valley for 250000 miles and still ran great when I sold it.