High Quality Chainsaw Bars Husqvarna Toys

How much more "wow" is in a 550?

weedkilla

Super OPE Member
Local time
9:03 PM
User ID
22
Joined
Dec 4, 2015
Messages
307
Reaction score
960
Location
lobethal, South oz
Country flag
I've had a husky 550 for a while and it's now my most used saw. I've done the easy stuff, it's muffler modded, squish is 018 with a thinner base gasket and I've cleaned up the ports. The transfers had some pretty ugly casting flash, all smooth and pretty now.
It'll happily pull a 64dl 3/8 setup in Aussie hardwood, it's nipping at the heels of how I remember my 562 when it was stock, or right there with an open ported 268.

Obviously I want moar....but its good enough I'm concerned about going backwards. There is obviously some thought gone into the transfers, a lovely curve cast into the back/top wall of the uppers. The uppers are slanted - I don't know what would change if I made them flat, or even if I could replicate the original shapes if I moved them significantly.
I don't see an obvious way to make it better.

Those that have run a well ported version - Whaddya reckon? Is it worth the time and a couple of Pistons to try and find some more go?

I'm moving house at the moment, so this is going to be rattling around my head for another couple of weeks before I even think about putting the jug on the big spinny thing.
 

weedkilla

Super OPE Member
Local time
9:03 PM
User ID
22
Joined
Dec 4, 2015
Messages
307
Reaction score
960
Location
lobethal, South oz
Country flag
I get big gains from the 550. Machine work is involved......and I'm not sure I could get good gains without that.

After I cut the squish, I set the exhaust port to 105, and the transfers to 115.
Any insight into flat vs factory taper on the transfers?
Those pretty shapes make me think that there was some serious thought put into swirl in the combustion chamber. I've done lots of staring at them and I'm more confused than when I started.
 

Mastermind

Chief Cat Herder
Staff member
GoldMember
Local time
5:33 AM
User ID
4
Joined
Dec 3, 2015
Messages
47,611
Reaction score
308,349
Location
Banner Springs Tennessee
Country flag
Any insight into flat vs factory taper on the transfers?
Those pretty shapes make me think that there was some serious thought put into swirl in the combustion chamber. I've done lots of staring at them and I'm more confused than when I started.

Cut a piece of card stock that fits from the squish band to just below the transfer openings. That will tell you if they are angled, or flat. Tell us what you see.
 

cgraham1

Here For The Long Haul!
Local time
3:33 AM
User ID
257
Joined
Dec 26, 2015
Messages
4,530
Reaction score
18,611
Location
Nor Cal
Country flag
Cut a piece of card stock that fits from the squish band to just below the transfer openings. That will tell you if they are angled, or flat. Tell us what you see.
Yes. Tell us what you see.
 

weedkilla

Super OPE Member
Local time
9:03 PM
User ID
22
Joined
Dec 4, 2015
Messages
307
Reaction score
960
Location
lobethal, South oz
Country flag
Will do, couple of days and I'll drop the jug again.
They were tapered, and I think the transfer curve worked with the taper. But off the top of my head I'm second guessing whether they were opening towards the exhaust or inlet.
 

psuiewalsh

Basement Bodging
Local time
6:33 AM
User ID
124
Joined
Dec 23, 2015
Messages
1,864
Reaction score
5,520
Location
Nottingham,pa
Country flag
Shaun Carr did a 550 for me and it is a good runner. I have a ported NE346 that Mike Lee did for me as well. I like them both for a 18" .325 fully buried and spitting chips.
 
Top