Gas Porting

I've been doing a lot of thinking and a lot of digging trying to find some answers. For a 72mm small block open with stroker crank really and good head would it be beneficial to gas port the piston so I can up the compression. I know this works well in like the 410 sprint car motors but haven't heard anything about the karting world doing anything like this. Have any of you done any research on this or even tried it.
 

IndyHarry

Member
You would probably get the tolerances to tight before you build enough compression to flutter the rings. Anything short of a methanol drag bike are trying to reduce drag and not increase it with more spring pressure.
 
I did forget to mention I'm using a Wisco that is cut down with only 2 rings. Would that make any difference, or am I just over thinking.
 

IndyHarry

Member
Nice technology . Ineresting read .
Can you get them in our needed sizes ?
I browsed through the online store and they seemed to have every millimeter needed but not sure on the thickness but that can be sanded. Just need to size up the top ring as the bottom stock ring should be fine unless they have that size too. Wouldn't hurt to call them with your specs to match up a set.
 
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flattop1

Dawg 89

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OVALTECH1

Premium User
hmmm... that’s kinda wild, when we had them done on the power adder engines they would be drilled straight down through the top into the backside of the ring land. I don’t know if I like the slots like that picture shows... looks like an ideal place for a detonation prone hot spot or a top ring to lift and cause a piston failure.
 

flattop1

Dawg 89
The picture has sharpie lines drawn on it .
Still anything that reduces ring land strength with nitrous could cause a problem .
 

Jimbo

You can fool some of the people some of the time
This is the piston i use for my Model 15 Briggs that meets the 14.5 CID and uses a stock stroke crank.
I have 2 sizes that get you closer to the 14.5 CID than a stroker crank and a 2.736" bore.
The big bore also unshrouds the valves way more than the stroker method.
 

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ted

Member
This is the piston i use for my Model 15 Briggs that meets the 14.5 CID and uses a stock stroke crank.
I have 2 sizes that get you closer to the 14.5 CID than a stroker crank and a 2.736" bore.
The big bore also unshrouds the valves way more than the stroker method.
Jimbo, do you keep these pistons?
 
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