Twisting distributer timing

[ejp2fast]

A while back when i did a valve job and had the distributer off, i did NOT mark on the distributer where the bolts were.... when i got it back together I estimated this and turned the distributer when the car was running and then when it sounded good tightened the two 12mm bolts..
So, my question is, being advanced, retarded, or normal, which would be for best mileage?
Which would be for best HP?
By turning the distibuter say in 1/8 inch increments (relative to where the top nut is) about how much degree advance/retard is that?

As I understand it, turning the disty counterclockwise is retard, turning it clockwise is advanced.

[FFesti_90]

retarded saves gas. we had to retared my taurus for a while until we could fix the intake gaskets. advancing it will give you more power and suck more gas

[ejp2fast]

moving 1/8th of an inch on the nut, what approximate degree advance / retard is that?

[jglutz]

Degrees on the crank are the same degrees on the Dist.

Looking at the festy disty from the driver's side... turning the dist Clock Wise advances the ignition.

Most importantly is to put a mark on the dist housing at TDC

The amount to move.....Inches/Degrees = (Φ·π)÷360°
Φ = Distributor Diameter
π + 3.14 (pi)

Retarding the timing for better gas milage....I've always been of the belief for the best milage...follw the factory settings.

[sanjeet]

buy yourself a strobe lamp or you can use the old proven method, mark top dead centre and rotate the engine so it is in the correct mark and that the dizzy rotor is pointing to No.1 cylinder, No.1 is the one by the timing belt cover, that will give you a point so you can start the engine I am unsure of the direction to turn so a strobe is the only way to take away the guess work, as a point jglutz I always time my Festiva as close to TDC and it responds better and give good MPG as well or Kilometers per litre, also make sure your vacuum lines are OK, they do tend to deteriorate and can effect performance.

and also remember when you re gap the plugs you need to reset the timing as well :glasses9:

[blkfordsedan]

Timing is expressed in crank degrees (i.e 6 Deg BTDC means the ignition fires when the crank is 6 degrees BTDC). The crankshaft and cam/distributor do not turn at the same speed. The advance, or early start of ignition is required to attain optimum cylinder pressure from combustion when the piston is just beginning it's downward power stroke. Too soon and peak cylinder pressure occurs as the piston is advancing up, too late and the piston runs away from the combustion. Burn rate remains consistent, regardless of RPM, and that's why there is some form of dynamic advance (mechanical or electrical) that increases as RPM increases. Just like shooting at a pheasant, you have to lead or anticipate time to allow the shot to arrive at the same point in space as the bird. Octane, fuel mixture, intake air temp, compression, burn rate, chamber design and plug heat range all effect the speed at which the mixture burns and as a result, the optimum timing. Higher octane, richer mixtures and cooler intake charges all have slower burn rates and require more advance. There are many fancy engineering formulas to help calculate the "perfect timing" that will release peak pressure when the piston, rod and crank have their best mechanical advantage. This generates the highest torque and also results in the highest combustion efficiency. What I'm trying to show is that power and efficiency are directly related. Hope this helps.
Anyhoo.......... If your car is running then you are "in the ballpark". If you just time it by ear, you can tell if your too far retarded because it will be sluggish and have weak throttle response. If you get it too far advanced it will crank hard when starting. This still leaves a substantial range of variation to achieve optimum timing. I used to hold the engine at around 4000 rpm and slowly advance the distributor until the tach needle just starts to vary up and down by a few RPM, then back off the timing slightly. If it cranks hard then back it off some more. It's far from being optimum and kinda redneck, but always seems to work. The best way by far is to use a timing light and set it to factory specs.

[ejp2fast]

thanks guys