Its all about timing

Mafia Mustang

Sep 17, 2006
Hey guys I have a 1990 mustang with an 86 engine in it that has been modded I am also using an maf. my question is how should I time this car? I can get it to start Im just young and dumb and am just learning how to use a timing light.
Thanks guys
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what im asking is like 10 degrees before top dead or something like that?

I don't even know where to start with you!

I would highly recommend that you go to Barnes and Noble or Borders bookstores and buying a book on basic engine theory, it would seriously cut the learning curve for you.

The degrees is referring to degrees of crankshaft rotation. The crankshaft rotates in the block 360 degrees per one crankshaft revolution. The number of degrees is referencing the relationship not only of the crankshaft to the piston, but of the spark plug's firing and the position of the piston in the cylinder.

There is a ten degrees before top dead center (top dead center is when the piston has reached the top of the cylinder), BUT there is ALSO a ten degrees "above" or "after" top dead center. To say that you've set the timing to ten degrees before top dead center is to say that you've set it so the spark plug will fire when the crankshaft is ten degrees away (in rotation) from pushing the piston (via the connecting rod) to top dead center in the cylinder. You would never want set timing to ten degrees "after" or "above" top dead center because then the spark plug would be firing after the piston is already supposed to be on it's power stroke (being pushed back down the cylinder from the force of combustion), which it won't do very well without the spark plug firing first!

In order to actually understand what you're doing when you're setting the timing, you may want to google search (or better yet, read a book) about what's going on during each stroke in a 4-stroke engine, because once you have a handle on that you'll be able to visualize what you're doing when you're messing around with engine timing.