Keith Gandy
Maxima K2 40:1 87 Pump Gas
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- 3:13 PM
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- 341
- Joined
- Dec 30, 2015
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- Provencal, Louisiana
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So far, on any Stihl 70cc-90cc that I have ever seen, you really cant go to big on the exhaust opening in the muffler.
They like them big, matter of fact, the bigger you go, the more power they have in the cut
The ported ones really come alive with a second large opening, like @Red97 makes
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I honestly don't know, but what I do know, is that there is one way to find out ........So on a big Stihl, like an 084, would they gain from running an open empty can?
You know I like a higher compression ratio than some builders do. But experience has taught me that there are no one size fits all recipes.
For instance in a milling saw....long cuts, and extreme heat. This is one example where excessive compression would be counterproductive.
It will if this is on the hood !!!
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The answers are:Couple questions.
If you deck a cylinder do ya need to raise ports what ya take off the deck?
If you go wider on exhauast port do ya do the same on intake.
think i heard exhaust can be wide as 70 percent of piston skirt if ring ends let you. What is the rule of thumb for intake port width.
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So you think carbon in your lowers are proof that burning charge goes all the way down to the case during initial transfer opening?
Yes. Heat in the jug causes some of the fuel additives to burn/breakdown, and/or there's some combustion that makes it down there at some point.How else would you have burned residue (carbon) down there? Everything else is clean as a whistle.
Do you have a theory?
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