Timing a 350

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MisterB

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Thanks for the info guys. Bought some new vacuum lines and spark plugs, but it got too cold out.

I did buy a new carb gasket and wanted to address this first considering all 4 sides of the intake manifold; where the carburetor base meets the intake, has tarnish running down. As soon as I stuck my socket on the carburetor bolts, I knew I had a problem. All 4 bolts were loose, the front 2 were no more than finger tight. I tightened them all down and took it for a spin, didn’t bother hooking a vacuum gauge up, too cold outside today. Runs a little smoother I suppose. I couldn’t get it to kick down before, now it does. Still hard to get it to kick down as it always has been. Oh well.

elevation is 1,000 ish.
New vacuum hoses all around are cheap and easy. Same with carb plugs. I'd do that and then let it idle and spray carb spray around the base of the carb and any of the fittings or carb plugs. If it changes the idle temporarily, you have a leak there.

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79dentside

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New vacuum hoses all around are cheap and easy. Same with carb plugs. I'd do that and then let it idle and spray carb spray around the base of the carb and any of the fittings or carb plugs. If it changes the idle temporarily, you have a leak there.

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Good idea, it runs pretty well now. I will do that the next time I tinker with it. Thank you!
 

79dentside

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Just an update. Between the leaking carb gasket, raising the idle a tad, new spark plugs, and tuning the a/f mixture screws on the quad, it steadied out and raised a little bit. I have not hooked the gauge up between today and when I timed the engine (when I made the thread), so I do not know which of the 4 things above that changed it.
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That’s good enough for me! Thanks for the help guys.
 

Goldie Driver

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Just an update. Between the leaking carb gasket, raising the idle a tad, new spark plugs, and tuning the a/f mixture screws on the quad, it steadied out and raised a little bit. I have not hooked the gauge up between today and when I timed the engine (when I made the thread), so I do not know which of the 4 things above that changed it.
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That’s good enough for me! Thanks for the help guys.

Nice gauge!

Mine does not have the pretty Christmas colors.

:)
 

Goldie Driver

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What did you wind up with for base timing?

I wound up at 9 BTDC- may have run slightly better at 10, but I was getting a little WOT clatter at higher speeds ( say 65 - 70ish after a 2 - 3 upshift.
 

79dentside

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What did you wind up with for base timing?

I wound up at 9 BTDC- may have run slightly better at 10, but I was getting a little WOT clatter at higher speeds ( say 65 - 70ish after a 2 - 3 upshift.

I haven’t even hooked a timing light to it yet. I should, I just know it runs good where it’s at. Might be good for me to know it, but on my old 305, it took 15 degrees initial timing to get it to the ‘Normal’ range of vacuum.... it had a little cam in it with some unknown internals, but my guess is someone messed something up causing a need for so much initial timing.

Moral of the story, I just shoot for good vacuum because the 8 degrees initial I had it at made it run like junk.
 

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