How many degrees timing advance MS 400?

[Duane(Pa)]

Spooky. Your backwards. The saw rotates counter clockwise when viewed from the flywheelside. You want to make the fly wheel go further or "advanced" in its position counter clockwise relative to the crankshaft so the spark happens sooner.

Magnet gets to the coil earlier

 

[huskihl]

Do u remember a 67 cc saw with actual torque? Ignition are so aggressive on the 680/620/7310, u dont have to mess with em.

Still in production and will over oil a 32" bar.

Most echos have aggressive timing like that which is part of what adds to their torque.

 

[wilfrie]

i like 10deg

I thought maybe the magnesium piston of the 400 couldn't handle the extra heat as well as the 362, and since they share the same flywheel, the 400 doesn't seem to be cooled any better than the 362.

But just to be sure, does anyone else notice the saw getting hotter with an ignition advance, or at least not experience any problems with it, not even in the long run, not even with a 10-degree advance? If that's the case, that reassures me, and I'll keep it that way. Thanks for the replies anyway.

It's strange, by the way, that they advertise the 400.1 as having improved cooling. If that wasn't a problem with the old 400, why does the 400.1 need better cooling?

 

[lehman live edge slab]

I thought maybe the magnesium piston of the 400 couldn't handle the extra heat as well as the 362, and since they share the same flywheel, the 400 doesn't seem to be cooled any better than the 362.

But just to be sure, does anyone else notice the saw getting hotter with an ignition advance, or at least not experience any problems with it, not even in the long run, not even with a 10-degree advance? If that's the case, that reassures me, and I'll keep it that way. Thanks for the replies anyway.

It's strange, by the way, that they advertise the 400.1 as having improved cooling. If that wasn't a problem with the old 400, why does the 400.1 need better cooling?

Just because even if not an issue better cooling won’t hurt. I believe the magnesium alloy piston transfers heat better to the cylinder than aluminum as one of the benifits. It was also lighter to put less load on the crank and bearings of the 362.

 

[huskihl]

I thought maybe the magnesium piston of the 400 couldn't handle the extra heat as well as the 362, and since they share the same flywheel, the 400 doesn't seem to be cooled any better than the 362.

But just to be sure, does anyone else notice the saw getting hotter with an ignition advance, or at least not experience any problems with it, not even in the long run, not even with a 10-degree advance? If that's the case, that reassures me, and I'll keep it that way. Thanks for the replies anyway.

It's strange, by the way, that they advertise the 400.1 as having improved cooling. If that wasn't a problem with the old 400, why does the 400.1 need better cooling?

They are also cooled by fuel when it hits the piston. Heat can be a good thing as long as there’s ample fuel and air to get the job done. Heat will make the engine run lean and running lean will make it run hot. Adding fuel will cool it down and make more power in the process as long as it has the ability to put out more fuel

 

[farminkarman]

i like 10deg

Same here

 

[wilfrie]

I find this an interesting video, because it seems that the MS400 with a MM and 6-7 degrees timing advance appears to be stronger than the new 400.1 with a MM and 3 degrees timing advance (which is about the max amount of degrees before it sounds weird, according to the owner). So it seems that, although the new 400.1 is advertised to have more torque, with the both mods you can do yourself the old 400 seems to overbridge that, and is ultimately stronger in practice(?) So a reason (apart from other reasons) to keep the old one instead of trading it in for the new one?! I am interested in your thoughts!

 

[lehman live edge slab]

I find this an interesting video, because it seems that the MS400 with a MM and 6-7 degrees timing advance appears to be stronger than the new 400.1 with a MM and 3 degrees timing advance (which is about the max amount of degrees before it sounds weird, according to the owner). So it seems that, although the new 400.1 is advertised to have more torque, with the both mods the old 400 seems to overbridge that, and is ultimately stronger in practice(?) So a reason (apart from other reasons) to keep the old one instead of trading it in for the new one?! I am interested in what you guys think!

Other than slightly lighter and possibly better ergonomics no reason to trade for new one but maybe just own one of each.

 

[Duane(Pa)]

Other than slightly lighter and possibly better ergonomics no reason to trade for new one but maybe just own one of each.

Sounds sensible to me. Prices be damned, I am going to get the "point one" when they are easily obtainable. I like the look and that’s something I just can’t say about too many new saws.

 

[president]

They are also cooled by fuel when it hits the piston. Heat can be a good thing as long as there’s ample fuel and air to get the job done. Heat will make the engine run lean and running lean will make it run hot. Adding fuel will cool it down and make more power in the process as long as it has the ability to put out more fuel

so would upsizing the semi fixed jets assist in cooling?

 

[lehman live edge slab]

so would upsizing the semi fixed jets assist in cooling?

I don’t think it would be needed on most of them since they can tune rich enough to save a saw from a minor air leak. Think only ones Kevin needed to make capable of going richer was the first version ms 261c. Think he was drilling the jets because they would sometimes go lean on him after porting them.

 

[huskihl]

so would upsizing the semi fixed jets assist in cooling?

Yeah if you ran out of screw adjustment. No reason to do it unless the screws didn’t allow enough extra

 

[bwalker]

I thought maybe the magnesium piston of the 400 couldn't handle the extra heat as well as the 362, and since they share the same flywheel, the 400 doesn't seem to be cooled any better than the 362.

But just to be sure, does anyone else notice the saw getting hotter with an ignition advance, or at least not experience any problems with it, not even in the long run, not even with a 10-degree advance? If that's the case, that reassures me, and I'll keep it that way. Thanks for the replies anyway.

It's strange, by the way, that they advertise the 400.1 as having improved cooling. If that wasn't a problem with the old 400, why does the 400.1 need better cooling?

Of course its going to be hotter. You are exposing the piston to heat for a longer period of time.
Will it hurt the saw? Not in my expiereance.