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Thread: Need Timing Help

  1. #1
    slp2002fh Guest

    Default Need Timing Help

    I'm a little confused with the ignition timing. I understand that timing should match the reading on the computer screen, but I can't get the engine running to check that. I'm assuming from reading the manual that I should unplug the 4 pin connector and set the base timing at 10 degrees. Is this correct? Is it possible to have numbers smaller than 10 degrees in the spark map?

  2. #2
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    22,748

    Default

    This is how I do it:
    If installing or replacing the distributor, follow the vehicle/engine factory service manual instructions. Temporarily disable the Idle Spark Control (the nonnumerical values require a restart to take effect because they're not 'real time editable').


    TIP:
    There is an easier way to synchronize the ignition timing, however you must have your Spark Map saved/copied somewhere. You can simulate locked-out timing advance, by entering the same value in every cell of the Spark Map. I like to use 30°. You can use the "Cell Action" function to automatically enter 30° in the entire map, so you don't have to do it manually. Also, temporarily uncheck the "Enable Idle Spark Control" box in the "Spark" drop down menu, so the idle timing doesn't rapidly fluctuate. This is not real time editable and requires a restart. Enable it after you're finished with the ignition timing. This is easier, since you won't need to look at the laptop computer while synchronizing the idle timing and the Propagation Delay.

    Without disconnecting anything and using a timing light, start the warm engine and turn the distributor to synchronize the engine's initial timing with the idle timing on the laptop computer. When the initial timing (idle) is synchronized, lock down the distributor's adjustment bolt and never touch it again (for this purpose). After synchronizing the initial timing (distributor hold-down bolt tight), ALL timing adjustments/tuning is done on the laptop computer.

    Then use the "Ignition Propagation Delay" function to synchronize the timing advance at the higher RPM (3000-4000 RPM). It's all 30°, so you can momentarily rev the engine, and watch for the timing to drift away from 30° to synchronize the Propagation Delay. Adjust the Propagation Delay until the ECU maintains itself at 30°. If at 3000 RPMs, the actual timing you see with a timing light is less than what's on the Timing Table (software), increase the Propagation Delay until it matches. If at 3000 RPMs, the timing light shows more than the Timing Table (software), decrease the Propagation Delay until it matches. You can adjust it while the engine is running. It is real time adjustable (click enter after each numerical change). Some applications use a setting well above the default value of 248 usec. Believe your timing light above all else!

    Think of the "Ignition Reference" as just a software setting; no adjustment or tuning required. With a GM HEI or Ford TFI, simply set it to 10 (it's not your idle timing) and forget about it. Conversely, the Ignition Propagation Delay needs to be adjusted to synchronize the timing at higher RPM.
    May God's grace bless you in the Lord Jesus Christ.
    '92 Ford Mustang GT: 385" SBF, Dart SHP 8.2 block, TFS TW 11R 205 heads, 11.8:1 comp, TFS R-Series intake, Dominator MPFI & DIS, 36-1 crank trigger/1x cam sync, 160A 3G alternator, Optima Red battery, A/C, 100HP progressive dry direct-port NOS, Spal dual 12" fans/3-core Frostbite aluminum radiator, Pypes dual 2.5" exhaust/off-road X-pipe/shorty headers, S&W subframe connectors, LenTech Strip Terminator wide-ratio AOD/2800 RPM converter, M4602G aluminum driveshaft, FRPP 3.31 gears, Cobra Trac-Lok differential, Moser 31 spline axles, '04 Cobra 4-disc brakes, '93 Cobra booster & M/C, 5-lug Bullitt wheels & 245/45R17 tires.

  3. #3
    slp2002fh Guest

    Default

    I appreciate the help. I did get it running and with the information you provided, I made sure I was good with timing at idle. I need to get a dial back light to check for full advance. Turning off the idle compensation was a big help!

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