Blitz30 - the dumb one: 5/24/2001 - 1/1/1900 11:55:22 PM

Basic Timing >>> REAL BASIC TIMING

Please either explain or give me a reference that explains how to start from scratch on timing a flathead engine. I have the engine and a timing light. I have never set up an ignition before. This engine has an electronic distributor; a pointer on the block; and a single mark on pulley on the crankshaft. The distributor is identical to those used on a SBC. There is no vacuum involved. So vacuum advance seems impossible. I do not know how to adjust the `mechanical` advance. I know that this is really elementary but I do not understand the answers to my question on detonation during accelleration above 55 MPH.

Jim Marlett: 5/25/2001 - 1/1/1900 8:24:37 AM

RE: Basic Timing >>> REAL BASIC TIMING

Do you have an MSD distributor? They are adjusted with different sets of springs on the centrifugal weights to get the rate of advance and with different colored bushings to stop the advance at different RPMs. They have instruction sheets for how to do this. To set the initial timing, forget about trying to figure out what 6 degrees is on your crankshaft pulley. The mark on the crankshaft already has it figured in. Just line up the mark with the pointer with the engine at idle. I know that Ford wasn`t always on the money with the timing mark, but it sure gives you a place to start without pulling a head to find top dead center. Now all you have to worry about is total advance at higher rpms. If your distributor is an MSD, it should have come with a blue bushing installed. This blue bushing cuts off advance at 21 degrees according to their info. That should be close to correct. You won`t be able to measure the advance if you have a simple timing light (like mine), but if it still pings, you probably need less advance. Put in a bigger bushing (the black one). If you do have an MSD flathead distributor, I`m sure you can get help from MSD. If you got it used, they will surely sell you all the components to make adjustments if needed.

Jim Marlett: 5/25/2001 - 1/1/1900 7:04:33 PM

RE: Basic Timing >>> REAL BASIC TIMING

I probably should have added the sentence I was thinking and didn`t type. If you actually have a converted Chevy distributor, the info I provided is not correct. If it is a GM product, it will almost certainly have too much advance built into it for a flathead and should be recurved. I don`t know the first thing about doing that on a GM unit, either. The MSD flathead units bear strong resemblance to the ones they make for Chevys, but they aren`t General Motors units. My info was strictly for MSDs.

Blitz30: 5/25/2001 - 1/1/1900 10:53:28 PM

RE: Basic Timing >>> REAL BASIC TIMING

Jim ~ It`s a 8BA Mallory Electronic. Thanks for the explanation. I also found the Techno Site ... There is a lot of information there! Thanks guys. I am learning thanks to you. Blitz30

Ron: 5/25/2001 - 1/1/1900 5:02:01 PM

RE: Basic Timing >>> REAL BASIC TIMING

Opening the dist advance mech. may not be a good idea if you never worked on one before. you can find your total advance this way. Measure the diameter of the pulley. X pie 3.14 is good enough. then divide by 360. This gives the surface distance the timing will move for a given advance. EX: 6` pulley, X 3.14 = 18.84 divided by 360 = .052` per/deg of advance. 24 degs total advance equals 1.25` or about an inch and a quarter. Think Ron

JWL: 5/25/2001 - 1/1/1900 7:31:55 PM

RE: Basic Timing >>> REAL BASIC TIMING

Tell us what kind (brand) distributor you have. Here is where I would start: Use a vacumn gage to set the initial timing at idle speed. Set the timing to the highest vacumn reading and then retard till the gage drops 1/2 inch. (of vacumn) Now follow the info Ron gave you to make a mark on the crank pulley at about 25 degrees before TDC. As you face the crank pulley, your new mark will be made to the right of the existing pulley mark. Start the engine with timing light attached and rev engine untill the centrifical advance reaches maximum travel and make a note of where the signal indicates that is in relation to the new crank pulley marking. If the new mark is to the right of the timing indication, the total advace is more than 25 degrees and probably far more than the engine needs. It has been my experience that most Flathead owners use more advance than necessary. It seems to be a status symbol to say that you are running 28 degrees (or some other number) when most engines like between 20 and 25 degrees. Based on the type of distributor you have, determine the actions necessary to limit the mechanical advance. Fix it at about 22 or 23 degrees total. (Total means the initial you established with the vacumn gage, plus the mechanical provided by the distributor mechanism) Next, as you have learned how to limit the total mechanical travel, you have also seen the method your distributor employs for returning the mechanism to zero. This is usually a pair of springs. For tuning the advance curve so the engine operates without ``pinging`` during acceleration, you can install different springs and/or change the mounting position of the springs. These changes alter the relationship of mechanical advance to RPM. It usually takes some testing to make your combination work to your satisfaction, but it is time well spent. As you make your setting, leave the timing as high as possible, so the engine is at the edge of ``pinging`` but not actually doing so.

JWL: 5/26/2001 - 1/1/1900 7:35:37 AM
RE: Basic Timing >>> REAL BASIC TIMING
Sorry, correction! If the new pulley mark shows up to the LEFT of the actual flash indication, (from the timing light) the advance is above 25 degrees. I must have been sitting in the drivers seat when I wrote previously.

Blitz30: 5/25/2001 - 1/1/1900 10:42:33 PM

RE: Basic Timing >>> REAL BASIC TIMING

JWL ~ Thanks. The Distributor is an 8BA Mallory Electronic. Thank you for the detail, it helps me to understand the process. Blitz30

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