262XP Day

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I like being in that minority. Figuring out what these little buggers like and grinding on them is really entertaining.

I used to be there. ;) Then I realized the wood didnt care how long it took 7 seconds or 5.

Thinking these were all ported. Maybe 1 was stock. Plus there was many others that were race ported not in pic. :D:p

10389426_10205493484473029_1212520556153990510_n.jpg
 
Randy, my english is not good and all this with porting the 262 is kinda new learning for me, hope I can ask for some porting ideas.

Inlet timing, i understand you prefer 72*. You dont work with the inlet, or did you widen it a bit?
What was the timing opening-close inlet timing?

Exhaust timing, did you change a bit there, and what ended your timings up to be there?
Did you widen up the exhaust port?

If I have got it correct, transfer timing 118*?

If there is anything I have overlook I would appreciate if you guide me on the correct way.

The machine work changes the timing on all the ports. But I raise both the exhaust and the transfer back up to about stock height. Ex: 103, Tr: 118. The intake is just where the machine work lowered it to. The intake has been widened.....and the roof has been raised a bit too. That gives me more area....but allows me a quicker closing point.

In Norwegian....

Maskinen arbeid endrer timingen på alle portene . Men jeg heve både eksos og overføringen tilbake opp til ca lager høyde . Ex : 103, Tr : 118. Inntaket er bare der maskinen arbeid senket det til . Inntaket har blitt utvidet ..... og taket er hevet litt for . Det gir meg mer område .... men tillater meg en raskere lukking punkt .
 
I use that, and width to gain area. Remember, the porting on these engines is measured in Time/Area. If you keep the time short.....you need more area. You'll still be able to fill the case, but you can trap, and transfer more. Really what we are seeing is a more efficient engine. Less spitback, less fuel usage, same power, if not more.

Thanks man. What's a good indicator a saw could use more intake duration?
 
The machine work changes the timing on all the ports. But I raise both the exhaust and the transfer back up to about stock height. Ex: 103, Tr: 118. The intake is just where the machine work lowered it to. The intake has been widened.....and the roof has been raised a bit too. That gives me more area....but allows me a quicker closing point.

In Norwegian....

Maskinen arbeid endrer timingen på alle portene . Men jeg heve både eksos og overføringen tilbake opp til ca lager høyde . Ex : 103, Tr : 118. Inntaket er bare der maskinen arbeid senket det til . Inntaket har blitt utvidet ..... og taket er hevet litt for . Det gir meg mer område .... men tillater meg en raskere lukking punkt .


Not the worst "Google translation" I have seen, even though it isn't perfect! :lol:
 
The machine work changes the timing on all the ports. But I raise both the exhaust and the transfer back up to about stock height. Ex: 103, Tr: 118. The intake is just where the machine work lowered it to. The intake has been widened.....and the roof has been raised a bit too. That gives me more area....but allows me a quicker closing point.

In Norwegian....

Maskinen arbeid endrer timingen på alle portene . Men jeg heve både eksos og overføringen tilbake opp til ca lager høyde . Ex : 103, Tr : 118. Inntaket er bare der maskinen arbeid senket det til . Inntaket har blitt utvidet ..... og taket er hevet litt for . Det gir meg mer område .... men tillater meg en raskere lukking punkt .
So, when grinding the roof of intake you want the quicker closing point to avoid spit back and improve efficiency? Or is there more
 
Thanks man. What's a good indicator a saw could use more intake duration?

That's a damn good question. To be completely honest, I study the original design with an eye on carb size, case volume, and transfer height when deciding where to take my intake height. When I started using less intake, unloaded RPM went higher. That was an unexpected result.


No....this one.

http://www.husqvarna.com/us/accessories/axes-pruning-saws/splitting-maul/

So, when grinding the roof of intake you want the quicker closing point to avoid spit back and improve efficiency? Or is there more

You'd only want to raise the roof and widen the intake when the area of the port was small. For example, on the MS660, I don't normally do anything to the size of the intake port. After all, IMHO it is already too low, and really needs less time/area.

Also, if you are saying about performance gains from less intake........there's a fine balance there. Too little intake, and the case is unfilled.........too much and all you gain is spitback.

You're a good friend Steven!!

Yes.......yes he is. I'm lucky to have a friend like Steven.
 
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