I have some timing tape that I will be installing today. Now to find my old timing light. Thanks for the idea

 

You want to read it down near the plug, away from the other wires, to eliminate cross talk- bet if you subbed in regular HEI, it would read differently. 6al is multi-spark, right? could be a faulty 6al or triggering on wire cross talk.

 

When I first started this motor I was using an HEI only with the same results. Keep the ideas coming I’ve been trouble shooting this on and off for two years. You guys are just getting started.

 

Your motor is really a two-stroke, so #1 is firing on each stroke.

 

 

haven't found dial-backs to be inaccurate,but this is a great catch and I'm kicking myself for not thinking of it myself

Important tip that the timing tape MUST match the diameter of the dampner, otherwise you'll get incorrect readings.

 

Check the timing at, let's say, 3000 RPM and let's see what you get. At this RPM, the MSD-6AL will only make a strong single spark for each cylinder. Assuming your mech advance is working correctly, this should give us about 54° ( without vacuum advance !!! ). This test will eliminate an eventual faulty multispark MSD-6AL.

Second test : Use cylinder #6 for the timing light and make the same above test. This will eliminate an eventual cross spark between cylinder #1 and an other spark plug wire.

Third test : Try to borrow a timing light with no dial back, just to be sure it is not your timing light itself...

There is also a very simple test I'm using from time to time :
First, disconnect the wire coming from the coil at the distributor cap. Use some adhesive tape and stick the coil wire not too far from a grounded metal part on the engine. 1/4" to 1/2" is great. Then, turn on the ignition key. The engine can't start without the ignition coil wire but you will ear/see the spark when it occurs for each cylinder. Crank very slowly the engine by hand. If you have manual transmission, you can use the fourth gear and have someone help to push the car forward ( very slowly ). You will get a spark each 90° on the damper. Note the indication on the timing tape when sparks occur. You can know what cylinder is firing by removing the distributor cap and observing the rotor. This eliminates any possible issues with the MSD-6AL, vacuum advance, mechanical advance or defective timing light...
This will show you the real base timing for sure. I think you should try it.

Tell us what the results are...
If you still find 34° with this last test, and if your centrifugal advance works correctly, and if your car runs well like this, then I'm stumped !

BTW, interesting phenomenon !

 

Ok here is an update…..I just went and bought another timing light (dial back) it reads the same. I also checked it with a normal induction light and timing tape….Same reading

If I move the inductor over to #6 will it still time the same?

 

Yes, it should !
Test #3 : OK, your timing light seems to be accurate !
Hummm, I said to "borrow", not necessarily "buy"...
Try and tell us about the other tests... especially the last and simplest one...

 

How could it? Yes, they're companion cylinders and at TDC at the same time, but #6 is TDC Exhaust when #1 is TDC Compression?

Is it that I just haven't had my coffee yet?

 

I wonder...have you verified that all the spark plug wires are in the right place on the cap? I was thinking about this and I did run into an engine once where the distributor was put in a tooth or so off...and rather than dropping it in right the owner just moved all the spark plug wires 1 post...

 

Cylinder #1 and cylinder #6 fire exactly 360° ( crankshaft ) from each other. So it's the same mark on the damper. The crankshaft has to make two complete revolutions to fire all the cylinders. If the timing light inductor is hooked to #6 wire, you will check it firing with the same "0" mark as cylinder #1 on the damper.
Believe me, it's true, I have done it many times !!!

 

I don't think its that unusual, I checked my timing not to long ago
just for reference and found mine to be 28 and thought that was
because of my 6al system, never had the chance to find out any
info yet about it but it runs really well so I'm not going to touch it
until I see trouble from it. by the way my motor is not a stock
small block.

Riggs.

 

[EDIT POST-COFFEE] Yeah, I just have to get my head wrapped around this - #1 is firing on every other crank rotation, and #6 as the companion cylinder is firing on the "off stroke", but at the same timing marks.

Not sure if this advances the troublshooting, but it was an interesting realization

 

As I previously said, this test can only eliminate a cross spark problem between adjacent cylinders / wires that could occur with cylinder #1. It would be very improbable that the same thing occurs with cyl #6 too...

Don't overlook my simple test procedure : it's easy and doesn't involve complicated devices ( no timing light at all ! ). If you find about 34° with this last method, you can be sure this is your real ( awesome ) initial timing.
My Vette starts jerking at part throttle with anything higher than 54° including 15° vacuum advance...

 

Try checking the timing at #4 and see if this gets you about 12 initial.

 

Been there, done that.

 

is your mechanical advance kicking in at idle?
so you have your initial +mech advance =38* or are you adding more mechanical advance on top of that?

 

If it is set at 34deg at idle and you retard it to 12 or 20 or whatever it's going to stall, you have to turn idle up and the idle fuel mixture screws might need adjusting.

Something simple is happening here that is being overlooked. What is your idle RPM ? @ 34deg

 

What kind of spark plug wires are you using? I have Moroso spiral wound wires and my timing light acts crazy with them. When I time my engine, I put a plain old resistance wire from the dizzy to #1 plug. That gives me a good steady light on the harmonic damper and the timing tab. Just a thought!