Piston Window Porting for 2T Boost Ports

I added a window to the piston on my 70cc case inducted kit. Its pretty easy and allows the premix to flow much easier into the combustion chamber.

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[Avantone]

Nice mod, and should also help small end lubrication. You're braver than me; I would have gone for two windows and retained a little more skirt strength. Thanks for the videos 👍

[TumTuhm]

I always window just because that’s how the original metrakit design was… I also cut the bridge out of the skirt. Seat dyno’d, no idea on impact. Most of the fresh charge is through the side transfers so 🤷‍♂️

Thanks for the hard work bud, I owe ya a coffee.

[brandoncox]

Dude. Awesome. Not many ppl want to share secrets

[maxpionier]

If you ever get access to a dyno, I would love to see you try your piston vs a normal one. I don't think you can see a big difference. Many garage tuners have their tricks, and maybe you are on to something here but I doubt it.

[tyleraugustine]

Ive seen the argument that by increasing flow through the boost ports while the ex port is open that the only real thing happening there is that you are losing more unburnt fuel through the exhaust at the scavenging stage. Personally I think you want a smaller amount of fuel to do the job without reducing efficiency. I have tried both ways and have had the best performance without a windowed piston but thats just me measuring by the seat of pants dyno. However I am just a common moron, and this is mainly just for the al gore rhythm. ❤ya 💋

[laneadams]

Weird question but do you know where to get transfer decals for puchs?

[splak_]

looks rad, but there is a 100% chance that I would ruin my piston lol

[meskalin]

Is a piston with windows always better than one without?