Help need .030 stock piston for mac 9

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Mike Anderson
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Help need .030 stock piston for mac 9

Post by Mike Anderson » Wed Dec 08, 2010 11:06 pm

Hi Everybody,
Can anyone spare or give me a leed on a new.030 piston for a mac 9? Needs to be a stock type piston no 9 ports. Any help will be greatly appreciated. Trying to avoid boring a good block to .050 the .030 piston I have is worn and is not a good enough fit to use.
Thanks in advance.
Later Mike (317)729-2418 fleagle14@embarqmail.com

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steveohara
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Re: Help need .030 stock piston for mac 9

Post by steveohara » Thu Dec 09, 2010 9:39 pm

Mike,

What kind of intake manifold are you using on your engine?
Steve O'Hara

Mike Anderson
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Re: Help need .030 stock piston for mac 9

Post by Mike Anderson » Fri Dec 10, 2010 7:30 am

Hi Steve,

I am using a stock intake, so 9 port piston will not work. Block hasn't been modified in the 9 port area so it isn't filled. I may have to bore to .050 to get a piston. Do you know of anyone who has pistons? Tried to reach Vince Hughes about .050 pistons he supposedly has but e-mail bounced back. A .030 over stock piston would make me very happy as the block has good bore at .030. Any help will be appreciated.
Thanks Mike (317)729-2418

ted johnson
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Re: Help need .030 stock piston for mac 9

Post by ted johnson » Fri Dec 10, 2010 2:19 pm

Hey, Mike, hang in there! One of our great gang of guys rescued me from this exact problem a couple weeks ago on the stock port Mc7 I'm putting together, and I'm sure someone will step up for you. ;) Ted

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steveohara
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Re: Help need .030 stock piston for mac 9

Post by steveohara » Sat Dec 11, 2010 3:00 am

Mike,

I will check my stock to see what I have.
Steve

Mike Anderson
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Re: Help need .030 stock piston for mac 9

Post by Mike Anderson » Sat Dec 11, 2010 8:46 am

That would be great Steve. Let me know as soon as possible. Vince contacted me and he has .055 pistons, I will have to use that size if nothing else turns up.
Thanks Mike

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steveohara
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Re: Help need .030 stock piston for mac 9

Post by steveohara » Sat Dec 11, 2010 5:19 pm

Mike,

Sorry, I don't have an .030 in my stuff. If I were in your position I would get a modern style piston that fits your engine without having to bore the cylinder and make a substitute reed plate without the opening for the back passage. The elimination of the piston port induction will not have any effect on the performance and the modern piston is better due to the bearing arrangement.
It won't be 100% original but you'll save a lot of bore life and won't have to make any permanent mods to the motor. The substitute reed plate is an easy piece to make since you already have the original to use as a pattern.
Regards,
Steve

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Scott Kneisel
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Re: Help need .030 stock piston for mac 9

Post by Scott Kneisel » Sat Dec 11, 2010 11:44 pm

Mike,
I may have one.
I am in Maine right now but when I get home Tuesday I will check for you. Hold tight and I will let you know. If you decide to go with a modern piston and a block off plate I would suggest Mc49E reeds as they are larger than the Mc9 reed but the same flat configuration. As long as you would be making a custom plate you might as well incorporate the larger reeds. I have those reeds in my stock Mc9. They work nice
Scott

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