New honda coils with advancing cdi?

The coil has 20* of advance available, use it how you need it. I'll give an automotive example of what I mean.

My 351C had about 28* of mechanical advance and another 25* or so of vacuum. I found that my engine liked 38* total, all in by 3000 or so.
So, I disconnected the vacuum (drag only engine) and checked, 14* initial and when rev'd it would go to 42*. I tried backing the initial down to 10* but that killed the "hit". So, I wanted 14* initial and 38* total. I pulled the advance plate out and mig'd up the slot that the pin rides in, limiting the movement to about 6*, then I assembled, checked, tore apart and filed, reassembled...wash, rinse, repeat, until I got my 24* of mechanical advance. So at that point I had 14* initial, 38* total, but, it was coming in too late, so then I started playing with various springs to effect the rate. I got one spring from a 391 truck engine and one from a slant six which gave me all in by 3100 I think it was without fluttering. (too light of a spring or running one spring caused timing flutter, bouncing 10* or so at any rpm)
Yes I lived in the sticks and no, there was no such thing as a "speed shop" where I was from, you made everything yourself.

So, how does this relate to a coil that starts out retarded by 20* and as rpm increases it allows it to advance back to 0*? Simple, what is the total timing you want? 35*? then set the initial low rpm timing number at 15* by not using a timing key and then as rpm increases you have your 35*! (or whatever you want)

It's a 20* timing variable guys, like I said, use it however you want to use it.
 
The coil has 20* of advance available, use it how you need it. I'll give an automotive example of what I mean.

My 351C had about 28* of mechanical advance and another 25* or so of vacuum. I found that my engine liked 38* total, all in by 3000 or so.
So, I disconnected the vacuum (drag only engine) and checked, 14* initial and when rev'd it would go to 42*. I tried backing the initial down to 10* but that killed the "hit". So, I wanted 14* initial and 38* total. I pulled the advance plate out and mig'd up the slot that the pin rides in, limiting the movement to about 6*, then I assembled, checked, tore apart and filed, reassembled...wash, rinse, repeat, until I got my 24* of mechanical advance. So at that point I had 14* initial, 38* total, but, it was coming in too late, so then I started playing with various springs to effect the rate. I got one spring from a 391 truck engine and one from a slant six which gave me all in by 3100 I think it was without fluttering. (too light of a spring or running one spring caused timing flutter, bouncing 10* or so at any rpm)
Yes I lived in the sticks and no, there was no such thing as a "speed shop" where I was from, you made everything yourself.

So, how does this relate to a coil that starts out retarded by 20* and as rpm increases it allows it to advance back to 0*? Simple, what is the total timing you want? 35*? then set the initial low rpm timing number at 15* by not using a timing key and then as rpm increases you have your 35*! (or whatever you want)

It's a 20* timing variable guys, like I said, use it however you want to use it.

Thanks!,.. This helps a bunch!,. I will be porting a thread in the Honda forum about doing this.
 
Anyone messing around with these? 2-3 karts on the local track runs them, and they have an huge advantage to us others with fixed timing at about 8*. I contacted the official honda dealer from my country about it, but he said there are 2 new versions, one rpm limited to 4000 and one limited to 6000, although i believe there must be another version, or a way to bypass the limiter, because these guys definitely aren't running under 6k rpm..

Hi there,

I'd like to know if this has been solved anyhow by now? I can attest that the UT2 coil that nrracing and others are selling as "non rev limited" (30500-Z5k-801) is indeed LIMITED to about 6200-6300 rpm. At speeds above 6000 it keeps skipping sparks and sounds and acts as limiter is on. I tried it with several coils of the same type, result is the same. The only way to go above 6000rpm is to use old UT1 non-limited coil. Yet the UT2 coil has its advantages in low rpm torque being far superior to one produced by UT1 coil. Has anyone found a seller for clone or whatever UT2 coils that are really unlimited?
 
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