Ignition timing & engine vacuum

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Aug 24, 2009 | 04:51 PM

86stepsideF150

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From: Germantown, MD

Ignition timing & engine vacuum

I decided to give my truck some love today, because it surely deserves it, and it's overdue. It's an '86 Flareside F150 302 EFI with 104k miles. How much vacuum should this engine create at idle?

Also, I need to set the timing. I removed the distributor to install a new ign. module and never set the timing after reinstalling it. I installed the timing light correctly and disconnected the SPOUT wire... But, I'm a little confused as to where the timing tag is on the timing cover. I was looking for a tag with labeled tic marks on the timing cover, but all I saw was like a big arrow. Do I just line up the mark on the vibration damper with the arrow on the timing cover?

Thanks guys

Aug 24, 2009 | 07:26 PM

bghnkinf250

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From: Bay Area, Unfortunately

The timing mark is on the passenger side of the engine, on the timing cover. It took me a while to figure out where it was (I am a Chevy guy and used to it being on the other side). There should be a big flat edge sticking out from the cover, which should be TDC when the mark is lined up. You might have to lean in and contort your body just to see the thing. Check the emissions sticker under the hood to see where yours should be - I think it is like 8 degrees or something like that.

Aug 24, 2009 | 09:09 PM

86stepsideF150

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From: Germantown, MD

Yea, I see the flat edge you're talking about. So that edge is 0* right? But, according to my emissions label I want 10* BTDC. Do I just advance the timing and set it a little under that edge or what?

Aug 24, 2009 | 11:09 PM

Franklin2

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From: Virginia

The actual graduations and numbers are on the damper itself. You may need to clean it to see them.

Aug 25, 2009 | 04:51 PM

forum155pl

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From: Spokane washington

my truck runs awesome with 13* of timing, i believe the factory spec is 10*

Aug 25, 2009 | 05:12 PM

lew52

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Yes they like some advanced timing , something for free , can't beat that... Lew

Aug 26, 2009 | 01:29 PM

86stepsideF150

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From: Germantown, MD

Oh I see, I'll have to clean my muddy damper haha. 13* it is!

So does anyone know what kind of vacuum I should expect my engine to produce at idle ??