perhaps a subtle, early warning of those $300 hand pieces getting closer to failure?My right hand hurts like hell Duane.
I'm having the same "strato charged my a.." thoughts.
85 is where the 661 is at after machine work.......and without touching a burr to the port. I like to see about 40 degrees of primary compression. The 661 ends up with 35.
I have no idea what that means, I guess that's why people send their stuff to you lolA certain blowdown number was not my primary goal. Precise exhaust, and transfer opening points are far more important in my opinion than blowdown.
This engine has a very small crankcase. Bore size has been increased to 56mm, so it has a shorter stroke than a 660. All that sort of stuff changes port timing considerations.
On a two port engine (like a MS660) we can get the transfers up as high as 114 degrees ATDC before the engine starts getting peaky. I think that is because the transfers are wide open and slow flowing.......sorta lazy if you can picture that. They need to open sooner so they have time to get the mixture moving.....
On the Dolmar 7900 the transfer opening point has to be much lower. That engine has a very tight crankcase, and very small, high velocity transfer tunnels. Port a 7900 like a MS660.......and you've built a turd.
Blowdown time isn't really something I think much about.
Here's another thing to ponder........
The 562XP has about 10 degrees of blowdown......
The PlumFund account has been set up.
Just waiting on bank account confirmation.
Should be 2-3 days
We will be running this until December 20th, 2014
I do too how do I buy some must have a shot at this
Yeah I'm picking up what your laying down,,, Ala the MS461 the 661 has the crankcase stuffers to help with building/boosting more intake charge velocity that gives these new saws better performance right @ stock form,,, even with the shorter stroke and barely smaller displacement. unless I have it inverted???A certain blowdown number was not my primary goal. Precise exhaust, and transfer opening points are far more important in my opinion than blowdown.
This engine has a very small crankcase. Bore size has been increased to 56mm, so it has a shorter stroke than a 660. All that sort of stuff changes port timing considerations.
On a two port engine (like a MS660) we can get the transfers up as high as 114 degrees ATDC before the engine starts getting peaky. I think that is because the transfers are wide open and slow flowing.......sorta lazy if you can picture that. They need to open sooner so they have time to get the mixture moving.....
On the Dolmar 7900 the transfer opening point has to be much lower. That engine has a very tight crankcase, and very small, high velocity transfer tunnels. Port a 7900 like a MS660.......and you've built a turd.
Blowdown time isn't really something I think much about.
Here's another thing to ponder........
The 562XP has about 10 degrees of blowdown......
His nickname is monkey mind, so banana holder make sense
Yeah I'm picking up what your laying down,,, Ala the MS461 the 661 has the crankcase stuffers to help with building/boosting more intake charge velocity that gives these new saws better performance right @ stock form,,, even with the shorter stroke and barely smaller displacement. unless I have it inverted???
and then you go creating more bannana stuffing places and flow angle enhancement... wowzer
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