Scooterotica

COME ON SEAN YOU'VE JUST DONE ONE!!

IMO your going down the wrong route here......and over complicating it.

Your future boost port will be usually open in line with your transfers. Mock the top end up and rotate the crank till the trans are just opening. This is where you want charge to flow through the windows of the piston and start to exit through the boost port. Draw a line on your piston from inside the inlet port. Now you have a reference point.
Now all thats to decide is do you want the windows to start to open in line with the boost port, if so have the hole 'bottom' on the line. Or fully open when the boost starts to open have the hole 'top' on the line. Or anywhere in between.

Boost ports don't tend to flow that much anyway so massive windows are questionable. Why not just cut two round ones, they will be stronger, flow sufficient amounts of gas etc....Like the MB pistons......



What about your inlet port are you modding that at all, apart from the boost port?

Hope that makes sense.

Adam

Yes, that all makes sense thanks.
And round holes certainly would be easier to do.....just drill them out and then smooth them with some emery or wet & dry.
Not going to be doing anything to the inlet, other than match the manifold, and won't be putting in a boost port to start with. Just gunna run it with the holey piston and see how it goes. But the holes need to be in the right spot for when (or if) I add a boost port. Cheers.

we can lead a horse to water adam ,but we cant make it drink.....

also the term "flogging a dead horse " comes to mind....

Who or what's the dead horse? Me, my reed valve engine with no boost ports(!) or this thread?
It's gunna work I tell thee, it's gunna work..................maybe. Possibly. Perhaps.

it will still run and work to some extent....
but the point is .....just not as good as it could do...which to me and adam seems a bit of a shame,considering most of the work is done.....
its almost as though you have fallen at the last hurdle.....

there i go again with more horsey references....