Drag season is over for me, so I performed a leak down check on my motor.I found 8-10% on the good cylinders,45% on a couple cylinders. The bad ones are leaking through the exhaust valves. I'm pretty sure that they are sooted up from not having nearly enough timing in the motor on my last pass. (Lost my mag, then while running late for the round miss timed it 14 degrees off)The question is, do I have to tear the heads off and grind the valves, or will this problem correct it self with a proper tune up?