dweed said:
What is the differnce between advancing and retarding the timing. Waht does each do. a friend of mine did my advanced timing but im real suree what that does. And waht does retarding it do?
Thanks
Dan
I not sure if your question is a serious one but here goes anyway.
Basically if you advance your timing you allow your engine more time to burn the fuel & air completely. Our cars should be set at 15 degrees before TDC (Top Dead Center) from the factory. With this setting the plugs fire 15 degrees before the piston is all the way up. If you advance it to 17 degrees to have 2 more in which to burn the fuel. Now the down side to this is as you advance your timing YOU MUST increase your octane level of the fuel you run. If you do not you will get knock or detonation.
When you retard it works the same just in the other direction. you could run less octane.
Regardless of what some people think Octane does not increase horsepower in itself. It is only a burn suppressant, more of it is needed when your timing is advanced because the heat of the cylinder walls can ignite the gas before the spark plugs fire. This is what detonation or knock is.
P.S. The octane level in fuel will drop as the fuel gets older. So these mini-marts (no-name gas) sell it cheap because usally it is old.
Sorry for the long post people, just thought I could help.