Husky Coil College

[RIDE-RED 350r]

Unlimited coil is a gain on a 346, but big saws don't necessarily have to rev to the moon.

I've come to learn that you are spot on with that, Joe. My modded 394 doesn't spool to the moon, but man it has POWA!

 

[PogoInTheWoods]

And a stock NE346 needs to be faster? LOL

 

[RIDE-RED 350r]

I don't think it's so much about simply being faster. For me at least, I have a harder time tuning with the limited coil if I'm trying to crank it up and see how high it can actually safely run. Limited coil was a royal pain after I ported my 372. Pig rich is easy enough. But with the limited coil, it's harder to tell if you went a little too lean when the limiter doesn't allow a good piss rev that has no pop to it.

 

[andyshine77]

I don't think it's so much about simply being faster. For me at least, I have a harder time tuning with the limited coil if I'm trying to crank it up and see how high it can actually safely run. Limited coil was a royal pain after I ported my 372. Pig rich is easy enough. But with the limited coil, it's harder to tell if you went a little too lean when the limiter doesn't allow a good piss rev that has no pop to it.

That's the only real reason to run a unlimited coil, ease of tuning.

 

[RIDE-RED 350r]

That's the only real reason to run a unlimited coil, ease of tuning.

Especially when you are working with a ported saw that has the ability to run significantly higher than the limited coil will allow.

 

[PogoInTheWoods]

I don't see any sense in having a limited coil on a ported saw anyway unless the porting is specifically designed to lower the range of the power band and any top end gains would simply be incidental (accidental?)..., which in actuality would be unlikely. Seems to me the main reason for a limited coil is also the reason there shouldn't be limited coils..., keeping a saw from over-revving, presumably from an overly lean condition, but also intended to limit it's capabilities after modifications. Someone unfamiliar with a limited coil who is also not very experienced at tuning will invariably tune the saw too lean anyway thinking it's four-stroking from the tune instead of being rev limited by the coil -- creating the very condition the coil is supposed to mitigate and eventually burn up the saw.
This would be free run tuning "by ear".

Pretty sure the only safe way to tune an unlimited coil is in the wood going from fat to just cleaning up and living with it right there --- good, bad, or upside down rpm-wise. Anything more bangs against the limiter and will be too lean. At least that's how I've come to understand all this.

 

[Adirondackstihl]

How many 346’s run 14k + in the cut?
My piped 346 will turn 13.5 in a 10x10 with a Hedgerow chain. And that’s with a light hand.

 

[Wonkydonkey]

Too the moon,,, And back again

 

[Wonkydonkey]

I don't see any sense in having a limited coil on a ported saw anyway unless the porting is specifically designed to lower the range of the power band and any top end gains would simply be incidental (accidental?)..., which in actuality would be unlikely. Seems to me the main reason for a limited coil is also the reason there shouldn't be limited coils..., keeping a saw from over-revving, presumably from an overly lean condition, but also intended to limit it's capabilities after modifications. Someone unfamiliar with a limited coil who is also not very experienced at tuning will invariably tune the saw too lean anyway thinking it's four-stroking from the tune instead of being rev limited by the coil -- creating the very condition the coil is supposed to mitigate and eventually burn up the saw.
This would be free run tuning "by ear".

Pretty sure the only safe way to tune an unlimited coil is in the wood going from fat to just cleaning up and living with it right there --- good, bad, or upside down rpm-wise. Anything more bangs against the limiter and will be too lean. At least that's how I've come to understand all this.

Just saying if you know what you got coil wise, then a tach will sort the deaf ears out from not hearing what thay should be hearing.

But I only say this from experience

Cheers

 

[PogoInTheWoods]

How many 346’s run 14k + in the cut?
My piped 346 will turn 13.5 in a 10x10 with a Hedgerow chain. And that’s with a light hand.

With a limited coil?

Point is, if a limited coil 346 is tuned too lean it'll still burn up turning 5k in a long cut even though it still only revs to spec on the top end.

Just saying if you know what you got coil wise, then a tach will sort the deaf ears out from not hearing what thay should be hearing.

But I only say this from experience

Cheers

Not arguing any of this. Just offering my perspective. Tach is fine. I use one on non-modded saws for those repeatable results they tell ya are 'spec'. But ya still gotta tune from fat up to spec with a rev-limited saw to keep from getting too lean, tach or no tach...., unless of course, it has a little red LED on the shroud.

Only thing a tach is good for on a modded saw is identifying and earmarking the gains from the mods....IMHO.

 

[RIDE-RED 350r]

How many 346’s run 14k + in the cut?
My piped 346 will turn 13.5 in a 10x10 with a Hedgerow chain. And that’s with a light hand.

I get what you are saying, but lean at 14k free is also lean at 13k in the cut, even more so in the cut vs free-wheeling.. I've always found that it's hard to get a saw engine fully up to temp unless its put in wood and worked. And I've found that what seems to be a good safe tune when spinning free ends up moving a bit leaner after working it in a cut.

My free RPM tuning is only to get a baseline, my final tune is to check for some 4-stroking when I lift in a healthy cut and a quick piss rev after a healthy cut.

 

[RIDE-RED 350r]

And only speaking for myself, I am thinking about running an unlimited coil in my 346 just to improve certainty of tune, not so much to gain free RPM. As I said above, banging on the rev limiter may be a safe state of tune, or maybe it's not. Can't tell if that rev limited piss rev is good to go or lean because it's not allowing you to get to that point. Is it bang-on?? Or is it 1/8 turn too lean?? Hard to tell with a blue coil.

 

[RIDE-RED 350r]

Just saying if you know what you got coil wise, then a tach will sort the deaf ears out from not hearing what thay should be hearing.

But I only say this from experience

Cheers

And the theory of tuning to specified max RPM is pretty sound, dot dot dot for a stock saw.

Is the specified max RPM the same as the set max of the limited coil on a given model?? Legit question....

 

[whitesnake]

Sooo...is switching to a black coil going to really lose that much performance? Just curious.

 

[andyshine77]

Sooo...is switching to a black coil going to really lose that much performance? Just curious.

Probably depends on the saw, and maybe which black/blue coil? I know I didn't loose any power switching coils on my 346 and my 372 came with an unlimited black coil. The 390 may be different, as I personally don't have enough experience with that model using different coils, and different timing. The few ported 390's I've rar all had black coils I believe, they all ran incredibly well.

 

[PogoInTheWoods]

...lean at 14k free is also lean at 13k in the cut

Precisely. A limited coil doesn't care about fuel/air conditions, just rpm's when it sees a threshold(s) being reached. Then it simply begins to either change timing characteristics or interrupt the spark, not operate a solenoid to correct for lean air/fuel conditions relative to rpm like AT or M-Tronic.

I can see someone preferring a limited coil for certain situations given a thorough understanding of the coil's power band and timing characteristics along with correlating modifications to a particular saw for a calculated result..., kinda what I think Joe was getting at earlier.

Would like to see the timing and power band specs for the limited 346 coil compared to the unlimited. Have never heard of an actual difference in power with an unlimited coil, just no top end performance increase realized when one is used on a heavily modded saw.

All I know about my NE346 is it screams and seems to have a perfectly acceptable power band for its' size with the limited coil bone stock. Scary little rascal!

 

[huskyboy]

And only speaking for myself, I am thinking about running an unlimited coil in my 346 just to improve certainty of tune, not so much to gain free RPM. As I said above, banging on the rev limiter may be a safe state of tune, or maybe it's not. Can't tell if that rev limited piss rev is good to go or lean because it's not allowing you to get to that point. Is it bang-on?? Or is it 1/8 turn too lean?? Hard to tell with a blue coil.

Get the saw started in the cut, turn the h screw out till it blubbers rich in cut then back off till it stops. Don’t go any leaner than that.

 

[andyshine77]

all I know about my NE346 is it screams and seems to have a perfectly acceptable power band for its' size with the limited coil bone stock. Scary little rascal!

I've ran stock 346's that were total dogs, and others that are factory hot rods. I've never seen such a large variance with any other model.

 

[Dub11]

I have one with the 14,100 rpm limit, and see some have found gains with that coil, I just prefer having a fully unlimited coil. Some 390's can spin a little more than others.[emoji6]

My MMWS 2188 has that coil on it works great. Of course I have it set at 13200.

 

[andyshine77]

My MMWS 2188 has that coil on it works great. Of course I have it set at 13200.

Sounds like a nice conservative work tune. Pretty sure after a little work I'll be real close to that 14,100 mark, but we'll see where she ends up, as this 390 will be getting mild port work.