1977 400 timing specs?

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I have a stock 400 engine with a new hei dist, just going to use as my daily driver, what would be a good timing spec to start at, it's a vacuum adv dist. 10-12 degrees btdc sound right?
 

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It also depends on how worn your timing set is-for this reason, Id adjust the timing @ idle where you pull the highest manifold vacuum reading.
 

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Sounds good to me, of course that's setting initial without vaccum hooked up. If you're at a high altitude you could try a couple more degrees and see if it likes it, get any ping back it off.
 
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Hi, I'm putting a timing light on my 400 ,vacuum adv plugged, this is where my line on flywheel lines up at idle, this is a crude drawing , but u should get the idea, my timing pointer has befor and after on it and my reading is on the 6 after. Where am I at as far as timing mumbo jumbo goes . Lol
 

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74 Shortbed

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You're 6* retarded, advance is before TDC..
 

1987 GMC Jimmy

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Oof, that's rough. Your engine's gonna run so much better when you get done.
 
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You're 6* retarded, advance is before TDC..

So I'm way off on my timing, ? Do I need to rotate dist to advance it. According to my drawing, what side of the zero degree mark should the timing be at when idling, Sorry for the questions, just trying to get this engine up and running for my son.
 
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74 Shortbed

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So I'm way off on my timing, ? Do I need to rotate dist to advance it. According to my drawing, what side of the zero degree mark should the timing be at when idling, Sorry for the questions, just trying to get this engine up and running for my son.
That is correct, rotate distributor counterclockwise to advance, should be on the left of zero that is before TDC, and with vacuum disconnected. Set it at 8* to start, then connect vacuum advance and readjust the idle speed.
 

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Wow!
Start at the exact opposite of what you've got goin on. Turn it to the OTHER 6.
I like your drarwing !.
World of difference.

6° retarded? Prolly won't get out of its own way! Wow, I'm blown away.
.......that would SUCK.
[yt]_98nEjz2zjM[/yt]
 
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That is correct, rotate distributor counterclockwise to advance, should be on the left of zero that is before TDC, and with vacuum disconnected. Set it at 8* to start, then connect vacuum advance and readjust the idle speed.

Thanks
 
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What a difference when u set the timing in the right direction Lol. I'm at 6 degrees before tdc instead of 6 degrees after. Now my only problem is my dist vacuum canister hits my alum manifold, I would like to get timing to 8-10 btdc, can I just mark my dist ,and pull it and rotate it 1 tooth and retime, or do I have to rotate motor to # 1 tdc with rotor pointing to #1 cylinder again
 

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You can put the housing where ever you want, bring the engine up on TDC on compression stroke, now pull the distributor and move it to wherever you want it and drop it in, of course it won't drop all the way down because the pump drive is not lined up, rotate the motor until it drops down then keep going to TDC on comp, line it up with #1 and see if it's in a good spot, if not do it over again until you get it where you want it, simple deal :D
 

Rusty Nail

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Lol? Distributor in one hand flathead in the other, how hard can it be? Did I misunderstand haha?
 
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