Can old 346xp be fitted with NE346xp P&C?

[bjorn773]

Brad, why was the 357 carb necessary?

 

[blsnelling]

Brad, why was the 357 carb necessary?

I'm not sure it did much for the saw. It's just part of what I did when I modded it.

 

[SawTroll]

Brad, why was the 357 carb necessary?

Probably not necessary, but in theory a larger carb will help making more power, if the outlet is up to it!

 

[epicklein22]

Of course they do, no problem!

Ya, didn't some one put a 346NE top end on a husky 350? I know the idea was kicked around before? Or maybe it was just the OE346.

 

[TRI955]

I personally wouldn't sweat it. I don't want to get into the whole debate again, but when we tested the 50cc saws recently, a stock OE 346XP was 2nd only to a NE 346XP. It was stronger than the 5100 and 260 in the wood we were testing with.

You know, you were most likely testing in the wrong kind of wood....

 

[SawTroll]

Ya, didn't some one put a 346NE top end on a husky 350? I know the idea was kicked around before? Or maybe it was just the OE346.

It will fit on the 353 and 350, but I would be a bit sceptical if the 350 bottom end will hold up long?

 

[Kansas]

But why not have the power of the new cylinder if he needs one and it'll bolt right on?

Thats easy to say however I thought you just said you wondered if it would work also? (It would be cool btw if it worked)

Just saying...OE is the sure thing from my point of view I admit I am no expert.

Bolting on and bolting on and working are two totaly different things in my world maybe not in the saw modding business?


Kansas

 

[BIG BEAM]

Is the bottom end the same in the NE and OE (crank and bearing wise)?Chances are if the crank and bearings are the same part# it may work.
DON

Did I mention I LOVE this place!!
DON

 

[SWE#Kipp]

I run a 50cc cyl/pis on my oe346xpg

 

[Jacob J.]

I run a 50cc cyl/pis on my oe346xpg

There's the answer...good work...

 

[blsnelling]

You know, you were most likely testing in the wrong kind of wood....

It was probably rotten, wasn't it?

 

[bjorn773]

I run a 50cc cyl/pis on my oe346xpg

Is that the NE346 50 cc P&C or the 350/353 50 cc P&C?

Also, on the carb swap that Brad did, a larger carb is not necessarily a good thing. You still have to maintain velocity of the a/f charge. Smaller venturi equals higher velocity. My experience has been large carbs help on the top end, but you lose torque on the bottom end. Granted, this is on 4 stroke engines.

 

[SWE#Kipp]

It's the 346ne c/p kit that i run on my oe346 body

http://www.youtube.com/watch?v=vt933FiKGcA

 

[bjorn773]

Well, I just gambled on a used 346xp OE on ebay. I probably paid too much, got caught up in the auction high. The ad said it needed a piston, we shall see. If I have to put a p&c in it, I'll probably go with the NE. Of course, by then, I'd almost have as much in it as a NE. If all else fails, I'll part it out.

 

[blsnelling]

Is that the NE346 50 cc P&C or the 350/353 50 cc P&C?

Also, on the carb swap that Brad did, a larger carb is not necessarily a good thing. You still have to maintain velocity of the a/f charge. Smaller venturi equals higher velocity. My experience has been large carbs help on the top end, but you lose torque on the bottom end. Granted, this is on 4 stroke engines.

But saws are only used at WOT. I've not noticed any ill affects at all with the saws I've put larger carbs on.

 

[bjorn773]

But saws are only used at WOT. I've not noticed any ill affects at all with the saws I've put larger carbs on.

I guess you're right there, MOST of the time, they're used at WOT. If you've had no ill effects, excellent. I have seen ill effects in motorcycles where too large a carb creates a dip in low end performance. A lot of guys think bigger must be better. But, we're not talking bikes, are we. Keep up the good work.

 

[bjorn773]

Brad, please don't take this as a personal attack, I'm just trying to learn as much as possible from someone who obviously has more experience in this area than I do. I like to gather all the info available before investing dough.

Have you ever done any timed cut comparisons before and after going to a larger carb? It makes complete sense that in a bucking saw, you'd want as much flow as possible, as you'd be at WOT all the time.

It seems in a limbing saw, the lower end would become more important. I personally don't run WOT very often while limbing. I run the saw all over the rpm spectrum, depending on the thickness of what I'm cutting.

 

[blsnelling]

I've only fitted larger carbs to 3 saws. My MS260 had significant useability issues before the swap. The 044 carb cured those problems entirely. The other two are my MS361BB and 346XP. I don't recall doing timed cuts directly before and after. Perhpas I did on the 361, but I don't recall.

 

[Banshee]

My experience has been large carbs help on the top end, but you lose torque on the bottom end. Granted, this is on 4 stroke engines.

Same holds true in the 2 stroke world, I believe. Or at least in the Yamaha Banshee atv's.
I've seen some really big carbs on drag 'shees. Some as big as 40 plus mm. Stock on a 'shee is dual 28mm.
They make a single carb conversions for the Banshee too that's suppose to give more low end power than the duals.

 

[blsnelling]

All of that is correct. However, chainsaws don't need torque off idle. If throttle response is good, a saw is used mostly in its upper RPM range, never down low. Low on a chainsaw would probably be 8,000 RPMs.