timing

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undicided
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timing

Post by undicided » Wed Dec 21, 2011 6:17 am

when distributor is not locked down and the vacumm advance is blocked off does the timing still run at 32* at wot, or should vacumm advance be connected and would it run better. I am just curious how this works I am always hearing different things for different people.
Last edited by undicided on Wed Dec 21, 2011 2:54 pm, edited 1 time in total.

cntry141iq
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Re: timing

Post by cntry141iq » Wed Dec 21, 2011 7:27 am

if you set it that way yes it does ... but it isn't automatic ...
Don't waste your time ... it is the only thing you can't get more of
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undicided
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Re: timing

Post by undicided » Wed Dec 21, 2011 7:44 am

cntry141iq wrote:if you set it that way yes it does ... but it isn't automatic ...
What's automatic mean

Ruagatr
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Re: timing

Post by Ruagatr » Wed Dec 21, 2011 7:47 am

He means it runs whatever timing you set it to for the "manual" (centrifigal) timing to generate. If you just unhook the vacuum port, and dont touch a distributor, no one will have a clue what timing it will generate. It you then set it for a total of 32 degrees, then it will work as you describe.

Charles

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crowhater
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Re: timing

Post by crowhater » Wed Dec 21, 2011 10:10 am

unhook your vac advance. Start your engine and check your timming. Now bring your engine to full power with the boat on the trailer and read your timing at full power. This is how you find out for sure what is going on. I want to know what my base timing is ( timing at idle ) and I also want to know when my advance comes in. If you are going to run weights you should know when it comes in and when all of it is applied. This is important for other things like Carb adjustment and plug selection. The best way to deal with all of this is to remove the vac advance and then lock up the weights. With your dist set up this way your timming is set at what your initial timing is. Set your timing at say 33* at idle and as soon as you come off idle you will be at 32*. You lose 1* of timing because of the rise of your dist gear on your cam gear. With your timing maxed your engine will snap up RPMs much quicker and your throttle response will be quicker. If the engine drags because of amount of initial advance you can either buy a reduction starter or you can switch to a toggle switch ignition with a push button for your starter. Push the button to spin the motor over with the ignition toggle off and once the engine spins up you click on the ignition.

I am a firm beleiver in the keep it simple method of doing things. I know for 100% what my timing is at all times. If I need to make an adjustment to clean up plugs I adress my carb or I change heat range on the plugs because I know 32* is a good safe area for my engine.
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jinotown
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Re: timing

Post by jinotown » Wed Dec 21, 2011 1:34 pm

Like everyone says, make sure you know your total timing at wide open throttle, max RPM. 32 is safe, you "may" be able to use more. The centrifugal advance should be tuned by someone experienced or use the factory setting to be safe. The vacuum advance works along with the centrifugal advance to adjust for engine load conditions but does not change the total timing. It helps control detonation during high engine loads by retarding the timing. It a good thing to have as long as the components are in good shape. It is best to hook the vacuum line up to manifold vacuum instead of the ported vacuum off the carburetor. "Ported" vacuum closes off at idle to control emissions by retarding the timing.
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