How do you advance your timing and how much to do it with no engine harm?

 

The only real way to do it is with a timing light. But basically you turn your distributor and keep a light hooked up to adjust it. Also I think you need to override your knock sensor when doing this so that your ECU simply doesnt retard it back to normal.. Im not 100% sure on that tho.

You can also use timing gears, which give you better control of valve timing. However its really not recommended to just shoot from the hip and not use a light.

Some people say to turn your distributor little by little, then drive your car after every adjustment. Drive your car up a hil and put it in a high gear (say 4th gear going up a hit at say 25mph) and listen for pinging... if you hear it, then back off your dist an increment. How big those increments are is up to you.