372 Pston swap/mod

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Mike how does this meteor piston look to you?Came in the mail today. Any grinding needed?

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It looks good,there are some little casting ridges to clean up in the windows,I would use a saw file to clean those up and smooth and blend them. It looks fairly sturdy,I think it may work well. Is that one destined for a 372 mod?
If you are gonna machine the crown and install it in a 372,there is one last important and simple step you must do before doing any port mods and putting it together.
 
I’ll blend them in. I was thinking the same thing. It’s just 268 piston. Nothing special about it. The plan is to have it machined to your specs
 
I think the piston may be a good alternative to the more expensive factory piston,mainly because it is beefier so I'm not so worried about the aluminum alloy quality,good work.
Don't modify the cyl. ports at first,install the piston with no ring,then lightly tighten the cyl. down over it. Then move the piston to TDC(By looking thru the ports),using a thin sharp scribe look in the ex. port and trace the outline of the ex. port on the piston,get right into the edges,then move the piston to BDC and do the same with the intake port. Remove the cyl.,and now you know exactly how much sealing your piston skirts have around each port so you can judge how much you can widen them,you want at least 2-3mm piston skirt sealing left on the sides. You can see where the rings are with the intake port and how much to bottom edge of the piston seals the ex. port. You can gently smooth your lines after with a Scotch-bright pad,no harm done.
Remember the 268 piston has a 1mm shorter skirts,so the intake port will be advanced 1mm for a little extra duration which is good.
Never grind the lower edge of the ex.port.
 
I don't think the whole page loaded when I first looked. All that sounds good. I'm bouncing between parts buying, building a stock 372xt and getting everything ready for my ugly betty 2 build with 268 pop up.
 
Here’s that 268 hyway pop up piston. It’s going in a 266. Thought I would share some pics of it
 

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Looked up machine shops near me this morning and it turns out there is one on my way to work. The owner ended up being a guy I’ve played rec basketball against for the last 10 years. They had it done in a few hours. $25.

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The tape is where the edge of piston ends. Does this cylinder look ground on already? I bought it used.
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Do you have to machine a lot off the 268 Hyway popup to fit it to a 372
I’m not sure about the hyway piston. This thread is just about the normal 268 piston. I did bring it up earlier because I was curious but mike said even with the regular 268 piston you’ll get about 200psi but he likes to raise the exhaust to the point compression comes down to 180. With the hyway you would get a mega pop up
 
I don’t see any reason why the specs mike wrote on the first page wouldn’t work with the hyway pop up. You would end up with a pop up on a pop up. No clue if there’s enough room for that in the cylinder
 
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