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How much more "wow" is in a 550?

weedkilla

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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

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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

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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

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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

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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

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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.
 
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