Mod husqvarn 322l xtorq trimmer

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I think I could still improve flow and retain the divider. This engine carb has the fuel jet pumping gas into the bottom passage but not the top. There is not a second butterfly controlling the strato flow. 98C03EA2-4AC3-461E-BA81-B07EBB03984C.jpeg
 
Oh and the transfer port can use a clean up. Sharp square casting edge needs to be removed. Very thin line under the shiny bit.
08C4A717-EBCC-4786-A4EE-A0469F277CB6.jpeg
 
So did some numbers.
Compression 90 psi
Squish 1mm
strato opens 91btdc close 81 atdc
intake open 77 btdc close 68 atdc
exhaust open 107 btdc close 118 atdc
transfers open 120 atdc close 130btdc

Compression I got 90 psi. I checked this against another machine and got same figures. Actually got 80psi off my good running machine. I’m assuming since it’s a fairly large squish and compression is not that high, this is an attempt to keep wear and tear down.

The above numbers are by no means scientific but are close enough.

Thoughts suggestions?

shave the jug for sure is on the list and as per previous, thoughts on removing the intake divider for the strato?

cheers
 
Imo leave the divider in, find a bigger carburetor, and open up the intake port more.
 
And what about port widths or timing and also compression? Is it worth smoothing the ports on the piston. Probably do it any way. They can be polished because it’s only airflow. Not air/mix.
 
So I’ve done most of what I had planned. I gauged out the squish by accident reducing compression. I tried using a boring bar and the jug is just to small combined with my lack of skill to get a good result. I’m going to chop into the jug base to fix it and mod the timing. I had planned to leave all timing standard. Anyways, I tidied up the carb but did not touch the Venturi. Widened intake and exhaust. The exhaust can be opened up more to the left because the Piston ring locating pin prevents widening to the right. Thinned out the divider. Didn’t make it to thin as I was worried about resonance and plastic fatigue. I don’t have a good set of fine dremel burrs to make the intake manifold look pretty but it all matches up.
Due to the lower compression from my stuff up it’s not going as bad as I wanted but already using less throttle to get moving.
 

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Fixed up the jug. I had to remove 1mm from the base to get compression back up to 90psi. That is a lot of material for little psi gain. But it’s a small piston with not much displacement. When I get a chance I’ll lay with the timing. This will take a backseat for a bit as it’s still runs fine now. Want to get the ms180 crank mod going.
 
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