390xp advice

[Ketchup]

Lookin real good. Think it will pull a 32”?

 

[Jake Dykstra]

Oh yeah. Leaned on it pretty hard in a couple cuts to see how it handled the being pulled down in the rpm range and was surprised how much it took. Also as soon as I eased up it pulled right back up to rpm.
I'll get the 32 on it today and make a few cuts.

 

[Jake Dykstra]

I think hwy really nailed it on this set up. It took a fair bit of time to lighten the piston to stock piston weight and get the transfers hogged out but other than widening the exhaust to 37mm and raising the roof of the intake to match bottom of piston at TDC its a bolt on deal.
I had no flaking issues.
Replaced .020 gasket with .010 gasket to get squish to .023
I don't cut commercial so I doubt I'll wear it out any time soon.
Not having to do any lathe work to get great compression and timing numbers is a real plus for most enthusiasts.

 

[srcarr52]

94.4 cc with the 57mm bore. That's a lot of displacement in a small package.

 

[Jake Dykstra]

Race video coming shortly!
Weighed both saws all topped of with fluids.
066 19lbs
390xp 18.5lbs
Guessing it will be 19lbs with full wrap

 

[Jake Dykstra]

The 066 runs great but is all stock with dual port muffler. I used same 32" stihl square ground chain on both. Rakers at .025. Not meant to be a husky vs stihl thing but there the same cc's (close enough anyway) and I like having something stock to compare to after I work on a saw. And being a $130 hwy P&C makes it even more impressive.
Great alternative to the $400 oem replacement.
I was surprised by the fact that the saws weighed the same fully topped off.
066 always felt heavier in the hands.

 

[pbillyi69]

nice job that runs really good.

 

[Ketchup]

The 066 runs great but is all stock with dual port muffler. I used same 32" stihl square ground chain on both. Rakers at .025. Not meant to be a husky vs stihl thing but there the same cc's (close enough anyway) and I like having something stock to compare to after I work on a saw. And being a $130 hwy P&C makes it even more impressive.
Great alternative to the $400 oem replacement.
I was surprised by the fact that the saws weighed the same fully topped off.
066 always felt heavier in the hands.

Lookin good! Do you have a 395 to run it against? Almost identical displacement, but some interesting differences in design.

 

[Jake Dykstra]

nice job that runs really good.

Thanks. Hope the cylinder last a while.

 

[Jake Dykstra]

Lookin good! Do you have a 395 to run it against? Almost identical displacement, but some interesting differences in design.

Not yet. Haven't come across a sweet deal yet

 

[Jake Dykstra]

Lookin good! Do you have a 395 to run it against? Almost identical displacement, but some interesting differences in design.

I have a 3120 or a 881 I could do a side by side with?

 

[Ketchup]

I have a 3120 or a 881 I could do a side by side with?

We all like saw videos. I’d be interested to see it cut just by itself as well. The shootouts are cool, but I can’t hear as well and that’s how I gauge speed and power. A tach would also be interesting in the cut.

395 is interesting because it’s the same displacement but 38x56 instead of 37x57 (more over square than most saws, very similar to 500i) and has side fed quads instead of bottom. It’s also a lot heavier and bulkier, plus the inside tensioner and outboard clutch. If a 390 can out cut a 395, that’s pretty cool.

 

[srcarr52]

We all like saw videos. I’d be interested to see it cut just by itself as well. The shootouts are cool, but I can’t hear as well and that’s how I gauge speed and power. A tach would also be interesting in the cut.

395 is interesting because it’s the same displacement but 38x56 instead of 37x57 (more over square than most saws, very similar to 500i) and has side fed quads instead of bottom. It’s also a lot heavier and bulkier, plus the inside tensioner and outboard clutch. If a 390 can out cut a 395, that’s pretty cool.

It wont.

 

[Jake Dykstra]

We all like saw videos. I’d be interested to see it cut just by itself as well. The shootouts are cool, but I can’t hear as well and that’s how I gauge speed and power. A tach would also be interesting in the cut.

395 is interesting because it’s the same displacement but 38x56 instead of 37x57 (more over square than most saws, very similar to 500i) and has side fed quads instead of bottom. It’s also a lot heavier and bulkier, plus the inside tensioner and outboard clutch. If a 390 can out cut a 395, that’s pretty cool.

Yeah I'll put a tach on it and try to do a pip showing the tach

 

[Jake Dykstra]

We all like saw videos. I’d be interested to see it cut just by itself as well. The shootouts are cool, but I can’t hear as well and that’s how I gauge speed and power. A tach would also be interesting in the cut.

395 is interesting because it’s the same displacement but 38x56 instead of 37x57 (more over square than most saws, very similar to 500i) and has side fed quads instead of bottom. It’s also a lot heavier and bulkier, plus the inside tensioner and outboard clutch. If a 390 can out cut a 395, that’s pretty cool.

Just the 390

 

[Ketchup]

It wont.

Yeah, not likely.

Do you think the 395 has design characteristics that make it a clear winner or just the fact that the 57mm jug is an over bore of a bad copy?

 

[srcarr52]

Yeah, not likely.

Do you think the 395 has design characteristics that make it a clear winner or just the fact that the 57mm jug is an over bore of a bad copy?

It's a bit of both.

The 395 has a larger intake tract all the way from the filter, and it's exhaust is already a bit larger and can go past 65% without having to taper the walls in towards the flange. It's also got a bore to stroke ratio that works well all around, big bars grunt or high rpm racing.

The 57mm bore 390 is obviously suffering from stuffed up lower transfers and probably poor gasket matching to the case. Bottom fed transfer ports don't work as well in chainsaws as they do elsewhere. This is because of the narrow bearing and case setup and the lack of crank reed induction means you have to keep the crankcase volume small which makes for a tight turn from the case out towards the lowers. It turns the case fed transfers into essentially a longer cylinder fed, loop transfer.

Sure it beat a stock 066 with a muffler mod, maybe a 7.5-8 hp saw but a decent ported 395 can easily make it into the mid 10's.

It's cool though, it will be a lot of power in a smaller, lighter platform with a much better filtration system than the 066. I'd hate to have to tromp through the woods carrying a 395, it'd get heavy quick.

 

[MG2186]

It's a bit of both.

The 395 has a larger intake tract all the way from the filter, and it's exhaust is already a bit larger and can go past 65% without having to taper the walls in towards the flange. It's also got a bore to stroke ratio that works well all around, big bars grunt or high rpm racing.

The 57mm bore 390 is obviously suffering from stuffed up lower transfers and probably poor gasket matching to the case. Bottom fed transfer ports don't work as well in chainsaws as they do elsewhere. This is because of the narrow bearing and case setup and the lack of crank reed induction means you have to keep the crankcase volume small which makes for a tight turn from the case out towards the lowers. It turns the case fed transfers into essentially a longer cylinder fed, loop transfer.

Sure it beat a stock 066 with a muffler mod, maybe a 7.5-8 hp saw but a decent ported 395 can easily make it into the mid 10's.

It's cool though, it will be a lot of power in a smaller, lighter platform with a much better filtration system than the 066. I'd hate to have to tromp through the woods carrying a 395, it'd get heavy quick.

That’s why like my 592!

 

[Jake Dykstra]

That’s why like my 592!

Yes! Another saw I need to get soon.
Bought like 20 saws in the last year so I'm trying real hard not to just order 1 of each

 

[srcarr52]

That’s why like my 592!

Yup, the 592 is has good power for the weight. The 395 has more big bar power though.