Project "I needed to clean the air filter so I blew the motor"

[sandblaster]

Thanks motorrad... yeah I edited my post after yours and after thinking  about it for a while this morning I can see the advantage over not overextending the rod length.  Base gaskets can do wonders..

USMC....  Keep watching and reading... I have had many revelations on this site over the last 3 years thanks to motorrads patience and the contributions of a few others.. you know who you are.   

[Motorrad]

Thanks motorrad... yeah I edited my post after yours and after thinking  about it for a while this morning I can see the advantage over not overextending the rod length.  Base gaskets can do wonders..

USMC....  Keep watching and reading... I have had many revelations on this site over the last 3 years thanks to motorrads patience and the contributions of a few others.. you know who you are.  

Rod length would make the opposite effect as what I do with base gaskets.   your thinking is wrong.    longer rod is like trimming the base of the jug down.


I want longer rod, to be able to fix the flaw we have discussed before with the exh port...   as it is, there isnt enough room for longer skirt, without it hitting the crank.

[sandblaster]

Nice....
I don't think I explained it very well but essentually what I was thinking was fix the trasfer port issue and allow for fine adjustment with thicker or thinner base gasket and mr dremel..

At the races and have a hard time typing on my phone..
My brother just crashed trail braking into turn one duri ng practice.
Everything is good but it was a little scary.

[Motorrad]

Okay. I wanted to run the top window port  as wide as the widest part of the rear boost port.

mocked it up in my Half jug.


and.   when the transfers JUST open.   the top of that port will already be roughly halfway down the wide portion of the rear boost port.


sooooo.


I can either cut it as a upside down trapezoid,  or make it square and the same width as the narrow portion of the rear boost port (same width as the previous "S" pistons)...


The pointed (stainless dental tool) marks where the top of the window port would be, when the ports open.






here is the top of the boost port (dental tool)





which is roughly here...   special note  (making my calculations based on WOSSENER piston machining, as there is a big step cut there in the crown...   )

[sandblaster]

Don't you just love your cutaway cylinder half  
I see black powder stuff...

[Motorrad]

Don't you just love your cutaway cylinder half  
I see black powder stuff...

yes... yes I do.

[Motorrad]

thoughts and oppinions on the piston boost port windows?

[alward25]

Looks like a great plan, need an engine to try it?  Want me to send you a piston?

[USMC 500]

USMC....  Keep watching and reading... I have had many revelations on this site over the last 3 years thanks to motorrads patience and the contributions of a few others.. you know who you are.   

OOHHHHHHHHHH!!!!!!!

Combined with the "cylinder cut away" thread and reading back on this thread all I can say is this!!!!

[81cr450]

I dont know if the skirts are tough enough for 3 holes.

I like the idea but

 

look at where mahle is puting their struts on modern designed pistons
 
I do like the middle high & tight like you have I think of the piston swinging around in there like swinging a bucket full of water in a circle, the most pressure is going to be in the very bottom. It also puts it opening above the reeds so they dont impede flow. I also vote rounded hole edges , nothing square or triangular as it focuses load. Just my 2-cent, from one who doesnt know

[USMC 500]

I dont know if the skirts are tough enough for 3 holes.

I like the idea but

 

look at where mahle is puting their struts on modern designed pistons
 
I do like the middle high & tight like you have I think of the piston swinging around in there like swinging a bucket full of water in a circle, the most pressure is going to be in the very bottom. It also puts it opening above the reeds so they dont impede flow. I also vote rounded hole edges , nothing square or triangular as it focuses load. Just my 2-cent, from one who doesnt know

+1 ............ok, ok.......I think I'm tracking all this now........

[Motorrad]

[USMC 500]

Well, we have a 3 window design......the teeth are low enough to close off the intake as the transfers open up...........I think we found a final design that will work!!

[motopunk]

Well, we have a 3 window design......the teeth are low enough to close off the intake as the transfers open up...........I think we found a final design that will work!!

indiana jones and the secrets of the piston scull... 

[Motorrad]

I dont know if the skirts are tough enough for 3 holes.

I like the idea but

 

look at where mahle is puting their struts on modern designed pistons
 
I do like the middle high & tight like you have I think of the piston swinging around in there like swinging a bucket full of water in a circle, the most pressure is going to be in the very bottom. It also puts it opening above the reeds so they dont impede flow. I also vote rounded hole edges , nothing square or triangular as it focuses load. Just my 2-cent, from one who doesnt know

hey 81. that pic isnt showing up.   can you re-post it ...  Im curious what your showing me..   also what its off of would be nice