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I probably didn't explain myself properly. (hope I'm not misleading anyone either!)

Bob has a method that says you record your engine idle vacuum, then remove the top of the carb and measure the vacuum port that leads to your power valve diaphragm ( He uses a vacuum tester). Where the diaphragm moves, record that number. Then you clip you powervalve spring till the diaphragm only moves at about -2hg less then your engine idle vacuum numbers.

In my case I thought about it when I vacuum checked my engine two days ago and saw some surprisingly low numbers. So it worked for me. But ofcourse it's certainly doesn't mean it's what's causing your problem. Most of the time one size doesn't fit all. Just thought it was worth sharing as your description was simular to my experience.
 

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I probably didn't explain myself properly. (hope I'm not misleading anyone either!)

Bob has a method that says you record your engine idle vacuum, then remove the top of the carb and measure the vacuum port that leads to your power valve diaphragm ( He uses a vacuum tester). Record that number. Then you clip you powervalve spring till the diaphragm only moves at about -2hg less then your engine idle vacuum numbers.

In my case I thought about it when I vacuum checked my engine two days ago and saw some surprisingly low numbers. So it worked for me. But ofcourse it's certainly doesn't mean it's what's causing your problem. Most of the time one size doesn't fit all. Just thought it was worth sharing as your description was simular to my experience.
I think you explained it just fine. It's just my brain that has a problem.

So, I have a total of five(ish) coils removed from the power valve diaphragm stem and it seems to idle MUCH better now. It's tunable, at the very least.

While I had the carb apart I thought I'd check the function of the idle cutoff solenoid. I held it against the body of the carb while my son turned on the ignition.
Um, in case you all don't know this, the ignition switch will engage the fuel pump.
If I hadn't been wearing glasses I would have had an eyeful of gas since a steady stream shot out of the upside-down carb top.

So, I know I have good fuel pressure and good flow as well. The burning skin on my face is a small sacrifice for this knowledge.

I will test drive it in a bit.
 

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If you look at the ground strap..it should turn color around 2/3 of the way up.
Your BPR6ES plugs are too hot of the heat range.
I could probably get some BPR7ES easy enough.
 

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I for one will try wrench 's spark plug advice. And maybe combine it with that cool simple plug mod from that other thread!
 

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Don't get me wrong, I think that Wrench FINALLY posted something helpful (It's a TRAP to make someone trust him later).

I am buying colder plugs. I have been climbing lower and lower and lower in the heat range since assembling this motor so I call it a diagnostic approach, shadetree mechanic style.

BUT, after modding the plugs with the increased gap and shaved grounding strap, it runs much better. The only other thing I did was to take the 5 coils off the power valve spring.

If the colder plugs run fine and don't foul then I will keep them.
 

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Redline 38 DGAS tuning tips.

Harold
Thanks Harold. I had seen that before but couldn't find it again, for some reason.

It appears I need larger idle jets? I actually thought the jets added air so I assumed that I needed smaller idle jets. Glad I read that again.

FWIW, that page was used to set my bench settings. IE, the carb had those baseline settings when I installed it.

I'm pretty sure I have .55 jets so I will see about those tomorrow.

Something to be noted is that the page refers to adjustment screws as singular when, in fact, both sides need to be done simultaneously.
 
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