Ported 026 Squish Check

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drf255

drf255

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Im at .0125 with .052 from the band and a flat cut piston. The machine work is on the money and I'm not freeporting.

How tight would you run squish? I'm planning on sanding the band to make it happen.

Compression should be right around 250.

I got the exhaust down to 104*. I could also ways add a beer can, but that will only take me to .016.

Thanks.
 
jmssaws

jmssaws

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I got a 066 that was 017 stock and it was completely worn out and had no sign of problems from a tight squish, I believe you can run a small saw tighter than a big one.
 
pioneerguy600

pioneerguy600

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Have you seen any case variation Jerry?

I think I'm gonna shoot for .019.

My compression should be high enough.

Not by very much, .002 low was the most so far, I tried 4 different cylinders and they measured the same, put them on other saw cases and all measured out thicker squish. Sthl does a very good job on keeping these saws within spec.
 
jmssaws

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Not by very much, .002 low was the most so far, I tried 4 different cylinders and they measured the same, put them on other saw cases and all measured out thicker squish. Sthl does a very good job on keeping these saws within spec.
I've checked tons of 660's and 002 is about the most I've seen. Husqvarna is right there with them.
 
Onan18

Onan18

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0.020 is generally regarded as "Safe" for a work saw. I have heard guys run 0.018 on an 026 with no problems but I wouldn't want to go tighter than that. I gave seen piston crowns beaten to the point of cracking on some engines with very little carbon.

Joe
 
jmssaws

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I ran a 460 for a good while that was bumping just a tad, I bought it that way and didn't check it,it was "ported" but they just took the gasket out and knocked a big hole in the muffler. Ran pretty good but had a funny noise that I had to investigate. Lol
 
Mastermind

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.0125????

Eyeballs-250pixels.jpg
 
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