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Sep 5, 2018 | 04:34 PM

gary's1950F1

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From: Brule Wisconsin

timing

I put a HEI distributor in my 352. Do I need to change spark plug gap or timing. Right now plugs are gap is at 45 and timing is 10 degrees btdc.

Sep 5, 2018 | 05:00 PM

85e150

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That sounds ok, how does it run? I think the OEM gap was in the .35 range. Stock timing may have been 6 degrees, but there are several reports of better running at 10. My own 289 ran better at about 10 vs. 6. Stand by, someone who actually knows something will be by.

Sep 5, 2018 | 06:31 PM

gary's1950F1

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From: Brule Wisconsin

It seems to start and idle ok but when I punch it from an idle it back fires. Its fine if the rpms are up then punch.

Sep 5, 2018 | 06:38 PM

ford390gashog

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From: Brentwood,CA

If it backfires that's an issue. Does your timing light have adjustments for timing? Set it to ten and look at the mark on the dampener. It may have slipped. Also what's your total timing?

Sep 5, 2018 | 08:58 PM

gary's1950F1

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From: Brule Wisconsin

No adjustments on the timing light.

Sep 6, 2018 | 10:22 AM

'65Ford

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Won't hurt to graph your timing curve. Measure the advance at initial with vacuum disconnected and plugged (if you have vacuum advance) and then in 500 rpm increments until you hit maximum advance. Then graph it again with vacuum connected.

I kinda doubt it's your timing curve though it may be ignition related...bad coil, for instance. Or maybe you have something loose in your distributor.

Is it back firing (up through the carb) or after firing (down through the exhaust)?

Sep 15, 2018 | 08:25 PM

99f350sd

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From: Lyndonville, Vermont

If its through the carb you may have an accelerator pump issue...Check the spray. Sometimes they stick sometimes they wear out...A little oil on the pin sometimes.