Machined hole in top of piston. Why???

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j par said:
Are you guys saying if I drill a small hole in each piston I'll gain horsepower?..
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thats what the LS guys do. How else do you think they make the power they claim to make?
 
j par said:
Are you guys saying if I drill a small hole in each piston I'll gain horsepower?..
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I told you about the compression enhancement holes a long time ago.
If 1 hole is good 2 is better. The second hole is drilled under the exhaust valve in the head, to help spent gases to excape.
 
j par said:
Are you guys saying if I drill a small hole in each piston I'll gain horsepower?..
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Just make sure you drill all the way through. If you can center it up and drill into the con rod, even better.
 
I have seen large bore pistons, pistons with the diameter of a 55 gallon drum that had a hole drilled and tapped in the center.
Those holes are used to thread an hook into so the piston can be lowered into the cylinder using a chain fall.
Why a small bore piston would have that is beyond me. If the hole is for manufacturing purposes, they must be using some antique equipment/ processes.
 
Krooser said:
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Thanks Krooser. That little video might prevent people from drilling holes in the top of their Pistons thinking that it's going to get a more horsepower than a Chevrolet. LOL
 
I laugh at the Harley engine design. Just a couple cylinders from a radial aircraft engine..
 
Yabut the sound;
Ba-bam------shugga-shugga------- Ba-bam-------shugga-shugga---------Ba-bam
ooooooooooooo
Lessee; 90hp, 110hp, 120,130,140, and
a 5hp transmission built in 1947.
I built a lotta 4 speeds back in the day.
Don't even talk about clutches.
But in fairness, those engines do make monster torque, compared to the lil rice burners............ and that is very attractive; well that and the 7000pound flywheel..... that is held on with one lil nut.
 
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my68barracuda said:
I have seen large bore pistons, pistons with the diameter of a 55 gallon drum that had a hole drilled and tapped in the center.
Those holes are used to thread an hook into so the piston can be lowered into the cylinder using a chain fall.
Why a small bore piston would have that is beyond me. If the hole is for manufacturing purposes, they must be using some antique equipment/ processes.
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Clark, cooper bessemer , dresser rand and others . Engines bigger than 4 car garages even v16 and v20 engines -------run for 30 or more yrs w/o a shut down .
 
It's all in how they were machined. In fact it's what machine they were machined on. If you have a fixture that holds the piston from the pin side you probably don't need a live center to support the head while it is faced. (flat tops only) Remember the old domed piston heads were just cast. The new ones are machined. Technology progresses.
 
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