Verifying ignition timing

Jerryl

Tall Chinese Guy
Dec 14, 2004
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I read a few threads on this. . . . . . but need some insight.
When placing the car in diagnostic mode, the timing gets fixed to 15 BTDC but mine is bouncing around and hard to read.

How does one accurately verify timing? :(
 

brian b

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Dec 26, 2008
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I would like to know how this is done as well. I beleive my BHJ internal dampener/balancer has the crank trigger wheel pressed on about 4 deg advanced (according to Otto, before he closed up shop). I would like to verify actual spark timing with out pulling the balancer off and measuring deg from center of the crank key way to trigger.
 
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RmvBfrFlght

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Sep 28, 2007
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Need to verify the damper and timing tab marks for TDC first. Need a piston stop for this, be sure to release the rocker shaft on the drivers side so a valve doesn't get bent on the stop.

Now that the damper and timing tab are verified for TDC (may need to add another mark or write down where it actually is when at TDC).

For this part, this is how I do it. First start and warm up the engine, timing verification should be done on an engine that is up to operating temperature.

At the ECM harness connector, remove the wire/terminal from location D5 (tan w/black stripe). This is the EST/BYPASS wire and puts spark timing entirely under ICM control.

Start the engine and check the timing with the light. It should be dead on at 10* BTDC.

Don't forget to re-insert the wire/terminal when done. Can also add a connector on the EST/BYPASS wire, that is how many other set ups with an adjustable distributor are.

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Jerryl

Tall Chinese Guy
Dec 14, 2004
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Houston, Texas
Need to verify the damper and timing tab marks for TDC first. . . . .Start the engine and check the timing with the light. It should be dead on at 10* BTDC. . . . .
RemoveBeforeFlight
Thanks a lot!!
Got the mechanical part done when the motor was rebuild.
Just to verify . . . . "bouncing around" is not acceptable at this point correct?
 

RmvBfrFlght

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Sep 28, 2007
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Thanks a lot!!
Got the mechanical part done when the motor was rebuild.
Just to verify . . . . "bouncing around" is not acceptable at this point correct?
It may bounce a degree or so, but otherwise should be fairly steady. With a quick-start system it is very steady. That may be the reason that folks with the q-start system report a smoother idle. And that the standard system just isn't going to be as smooth at idle.

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Jerryl

Tall Chinese Guy
Dec 14, 2004
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It may bounce a degree or so, but otherwise should be fairly steady. With a quick-start system it is very steady. That may be the reason that folks with the q-start system report a smoother idle. And that the standard system just isn't going to be as smooth at idle.

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Thanks! . . . . PM me your paypal info please . . . for a token of my appreciation.
 

charlief1

RIP Charlie!
Sep 20, 2007
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If you look at the timing indicator there's a hole on one side of it. That's for a magnetic probe that is supposed to be used with certain daignostic machines. It's used to varify timing through the machine rather than using a timing light. The machines are antique now but you might find one of them on evilbay or craigslist if you really want one of them Jerryl.:)
 

mgmshar

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Feb 20, 2002
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If this was a "Which turbo" question it would be 5 pages long by now :eek:

TTT as id also like to know.
For this problem, I would recommend a TA-49 or possibly a TE-44. Should be plenty of turbo to verify timing with...

:eek:

Actually, I've been wanting to do this for years. Glad somebody is asking, and people are answering.

Regards,
 
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RmvBfrFlght

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Sep 28, 2007
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Thanks! . . . . PM me your paypal info please . . . for a token of my appreciation.
This is not necessary. I have read many good posts on other issues. Just returning info back to others that I've worked through (believe me, I've had enough of my own).

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bison

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Dec 19, 2005
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This is now a sticky since its been posted several times in the last year and should be at the top.
 

turbodave231

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May 24, 2001
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To add to what Bob said: The TR6 module allows the user to fix timing at 10 degrees and then check with a timing light. I have tested this function and it works great! The TR6 also measures and displays cam sensor phasing. I found and corrected errors that I never knew existed. Both are very useful functions.
 
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RmvBfrFlght

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Sep 28, 2007
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Thanks for sticking it Brian, note also that the TR6 ignition has a built in mode to do this. The aftermarket ECMs may be able to do this as well.

Bob
Yes to both. The EBL SFI-6 ECM has this capability. Although it is better to open the EST/BYPASS line as it eliminates the ECM. The timing is completely under the control of the ICM for verifying it.

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HighPSI

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The aftermarkets have the ability to verify the timing also.

With an XFI (1.540 or newer software): Hit the [F5] key which will take you to the Global Parameters screen. Select "Fixed Timing" and then put a value beside it that you want the timing locked to. Then hit "Apply" at the bottom of the screen. I usually select a value that you have a known, good mark on the balancer to shoot. On BHJ balancers, I usually select 30 degrees. You willl need to adjust the Crank referance angle up or down until the timing on the balancer matches the timing you are locked to.

With a BS3 System: Select "Configuration", then "Operating Parameters Configuration". Select "Enable Timing Test" in the Static Test Timing box. Then put a value below it that you want the timing locked to. Then hit "OK" at the bottom of the screen. Once again, I usually select a value that you have a known, good mark on the balancer to shoot. On BHJ balancers, I usually select 30 degrees. You willl need to adjust the Crank referance angle up or down until the timing on the balancer matches the timing you are locked to.

With the timing set and locked, rev the engine up and verify the timing doesn't move. If it does you will need to adjust the Inductive Delay.
 
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larry33kc

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Aug 19, 2001
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Is there a trick to getting a light to work right on these cars. I have had three lights on this car and I can't get any of them to work more than a couple of flashes.
 
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