No point in arguing "how many fairies can dance on the head of a pin?" Jus' DO IT!
These pistons cost what? $10? DO IT! Drill the puppy. Drill an old one if you have to.
This is a Blaster piston I wanted to know if enlarging the back transfer would have an effect:
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Well used $100 piston, going under the knife, er, drill.
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Pilot drilled
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It's like 15 minuttes to pull a jug on a Blaster, less than 10 minutes to do it on a China Girl.
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I tested it between all operations. It actually worked better every time so far.
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Here you can see the port match up just below TDC.
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TDC, cannot match up the piston window to the cylinder window or there would be no piston skirt support. These pistons are weak so we don't touch the lower skirt. Engine was rippin' pretty good here. So if a little was good, let's keep going:
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Starting to act a bit odd. Lots of rev but torque disappearing. Why?
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Strange stuff happening now. Rev happy but kinda flat. How many times has this old piston been in and out of this motor?
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Little by little I filed the top port larger to see what it would do. Into the motor, test it, back out and file.
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Mister Happy Face! Well, not really. It was kinda sucky by here. This took up a sunny Saturday afternoon and I learned something. This piston was in and out of the motor about 6 times. Piston and bore were do for a replacement but still worked OK, so let's learn something from the last day of its life. Now, the things you can do with epoxy:
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