Timing 2F with Vacuum (1 Viewer)

love2fly

Flying the Mountains of the NW
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Timing the engine with a vacuum gauge is something I have not done in many years. Usually run with ball on pointer (7deg BTDC). So correct me if wrong on my set up. Trying to gat a better fuel burn for emissions testing (CO%).
This is using one of Trollholes electronic dizzy on a 2F no emissions engine.
I did what is listed below but due to the caps clip on the dizzy I can not rotate it any further due to it hits the pushrod/lifter side cover.
It would to go even higher that 50 inch but that as far as it go's then hits the cover.
I took a picture of the timing mark with the strobe light but did not catch the ball so I put a mark representing were it is now at on timing.
Seems to run fine and on rattles, good power, not sure about any detonation taking place.
Also would this be around 12 degrees ATDC?

Thanks

1. Connect vacuum gauge to the brake boost vacuum hose in my case.

2. Disconnect the dizzy vacuum advance hose and plug.

3. Loosen the distributor for rotation.

4. Connect timing light and rpm gauge.

5. Start engine run @ 650 rpm (idle).

6. Turn dizzy while watching the Vacuum gauge needle move to its highest reading while advancing the dizzy.

7. When the highest reading on the Vacuum gauge is reached retard the dizzy back to one inch of vacuum lower.

8. Reset engine RPM and mixture to standards and snug dizzy nut .


IMG_20200113_151346030[1].jpg
 

love2fly

Flying the Mountains of the NW
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I believe I found a few good post on this question here on the site. I guess I just need to make sure I am not to far advanced.

Thanks
 

love2fly

Flying the Mountains of the NW
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Thanks JC, I have to ask would you know if one adds degree of advance to timing for every 1,000 foot of elevation to the 7 degrees BTDC, such as I'm at 4,000' + 4 = 11 degrees?
As mentioned I can not turn the dizzy all the way to its fullest advance due to the spring clip on the dizzy cap hits the P-R cover so looking for a different approach to advancing.
Cheers
 

love2fly

Flying the Mountains of the NW
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I was thinking of that today. I didn't notice that I do have the indented cover for the stock dizzy just Trollhole's dizzy seems to be a bit lower.

Thanks
 
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If ur tuning for DEQ emissions carful you don’t over advanced the timing as this starts to create excess NOX and Hydrocarbons,
 

love2fly

Flying the Mountains of the NW
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Yes it is mostly to fight the CO% problem I had. Some say retard the ignition but I found that for me that was no help. So from the picture above with the timing mark I now have the timing set to when looking at the timing window the timing ball is now about one ball past the pointer. I had it pretty high, this seems to be the sweet spot for this 2F along with setting the carb with the vacuum gauge.
Cheers
 
Joined
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If stock is 7 degrees, I think 'ball just leaving the window' (as shown in your pix) is 12, and that's where I ran my carb'ed FJ40 for years at 7000' elevation. It would ping at lower elevations, when set to this value. Ultimately, you want an easy-starting, good running engine that doesn't ping, and if you have that, you're there.
 

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