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I recently took my 69 to a Dyno shop and asked them to dial in my motor. It's not stock so I'm essentially starting with a fresh 468 BB that needs dialed in. I drove the car home but just barely made it. It started backfiring through the carb and surging so bad I had to pull over. I called the shop and they were perplexed. I tried another shop and surprisingly had a similar situation.
So, I suppose if I'm going to dial this in its up to me and Ive spent the last week reaching the first step.

The engine has new MSD 8360 billet ready to run. The first thing I needed to do was get it ready to run. I ran into a snag however. With VA can plugged, I checked the initial timing and it was set @ 16*. Then, with my dial back timing lite, I check the initial and mechanical and find 45* @ 2800-3000. Thats way too much. I want 34-36.
The math doesn't add up. I should have seen 18* + 16* = 34*
So, just as a double check, I change the stop bushing from black (largest-18 degrees) to blue (21 degrees). 21 mechanical + 16 initial gives me 37* which I can adjust down to 36* easily. I check again and I'm still @ 45* @ 2800-3000. Va still plugged.
The change in stop bushing resulted in no change. By my reading here, I need to have ignition squared away first before I take on carb adjustment. (It's a Holley Ultra Street Avenger) So i'm kinda at a standstill till I get this figured out.

Has anyone experienced a problem like this? The timing lite is fairly new but it is possible that its reading incorrectly. I have a backup lite but its not a dial back.
 

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I've got an MSD 8361 on my BB which is similar to yours and have the black bushing installed as well as the vacuum line plugged into the manifold vacuum port on the carb, not "ported". I way I set mine was running it up to about 3000rpm with the vacuum advance off and set it to 36 degrees. I'm using an MSD tape on my damper. Everything else fell into place fine after that and I only had to tweak the springs to set the curve.
 

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try using your other timing light and see what happens I had a problem with a new snapon light went back to my cheap autozone plain jane light and problem solved somtimes simple is better
 

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When you had the black bushing installed what color springs did you have installed? Try the black bushing and 1 heavy silver spring and 1 light silver spring. Run the rpms up to 3500 and set the timing at 38 with your old light. Have someone rev the engine so you can check when the timing is all in.
 

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Follow Ben's suggestion, Post #3, use an older timing light - analog.
Aftermarket Ignition boxes play heck on digital timing lights.

Also, the scale is marked from 0° to 10°.
Use the scale and transfer to harmonic balancer and keep remarking until you get to 50° BTDC.
Don't worry about being a 1° or 2° off, you'll never be this accurate.
 

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Also, try using timing tape suitable for your balancer size. It's super convenient and for me a lot easier to read and you also don't need to screw with dial back buttons. However get a quality read as suggested.
 

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As others have said, set your total timing with a dial-back timing light. Try a different light if you suspect yours is having an issue. But if you're not using the vacuum advance, you really need to remove the vacuum can and replace it with the provided lock out plate. I just did this and it's kind of a pain, even with the distributor out of the car. You'll need a pair of snap ring pliers and some patience.

See page 7 below:

http://www.msdignition.com/uploadedFiles/MSDIgnitioncom/Products/distributors/8360_instructions.pdf
 

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All MSD 'Ready to Quit' disasters are internal module, failure prone, but, NO separate ignition box. Blaster coils WILL eventually cause the coil and RtQ module to fail.

And, as posted on so many sites it isn't even funny, UNLESS THE ENGINE IS ELECTRONIC FUEL INJECTED, WITH COMPUTERIZED TIMING...........DO =NOT USE A DIAL BACK TIMING LIGHT, INSTALL A TIMING TAPE, AND LEAVE THE DIAL BACK FEATURE OFF, OFF, OFF, OFF, OFF.

Also, not using the vacuum advance, correctly set up and on full manifold vacuum, DO NOT EXPECT TO GET THE IGNITION SYSTEM AND ENGINE TUNE TO WORK, PERIOD.

NOT yelling, but, simply being emphatic, yet again. I fix this kind of stuff day in, and, day out, EVERY DAY.
 

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All MSD 'Ready to Quit' disasters are internal module, failure prone, but, NO separate ignition box. Blaster coils WILL eventually cause the coil and RtQ module to fail.

And, as posted on so many sites it isn't even funny, UNLESS THE ENGINE IS ELECTRONIC FUEL INJECTED, WITH COMPUTERIZED TIMING...........DO =NOT USE A DIAL BACK TIMING LIGHT, INSTALL A TIMING TAPE, AND LEAVE THE DIAL BACK FEATURE OFF, OFF, OFF, OFF, OFF.

Also, not using the vacuum advance, correctly set up and on full manifold vacuum, DO NOT EXPECT TO GET THE IGNITION SYSTEM AND ENGINE TUNE TO WORK, PERIOD.

NOT yelling, but, simply being emphatic, yet again. I fix this kind of stuff day in, and, day out, EVERY DAY.
Every small block and big block car I've done has been 8360 and no box.

No failures ever.
 
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