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Main Area => Projects / Builds, Racing and Tech => Topic started by: 5thAve on March 22, 2012, 02:28:49 PM

Title: Pls help: cylinder modifications
Post by: 5thAve on March 22, 2012, 02:28:49 PM
I have a project that is stalled and I am trying again to solve a problem. See my post here:
http://www.gstwins.com/gsboard/index.php?topic=48095.0 (http://www.gstwins.com/gsboard/index.php?topic=48095.0)

In short, the design of the Wiseco 78mm piston changed so the pistons I received do not fit under a stock head. I need to learn if it is possible to reshape the combustion chamber in the head, and/or mill the pistons so they will work together and have reasonable compression ratio.

I'm looking for any members who have done work in shaping the combustion pocket or know someone who has done.

And yes, I realize the risk of all this is blowing up the engine.

Anybody have some advice for me? ^-^
Thanks!

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Title: Re: Pls help: cylinder modifications
Post by: burning1 on March 22, 2012, 07:31:02 PM
I ran into the same problem on my GS450 hybrid build. There are a few options... You could use a die-grinder or flex shaft to open up the combustion chamber, or have it CNC machined. Or, have custom pistons built.

My plan is to grind the head. If you're not in a rush, hang on, and I'll let you know how it goes. Might even be able to perform the work for you.
Title: Re: Pls help: cylinder modifications
Post by: mattnes17 on March 22, 2012, 07:51:45 PM
Quote from: burning1 on March 22, 2012, 07:31:02 PM
I ran into the same problem on my GS450 hybrid build. There are a few options... You could use a die-grinder or flex shaft to open up the combustion chamber, or have it CNC machined. Or, have custom pistons built.

My plan is to grind the head. If you're not in a rush, hang on, and I'll let you know how it goes. Might even be able to perform the work for you.
Looking forward to this ^^ if all goes well i might be cracking open my engine for some various modification plans.
Title: Re: Pls help: cylinder modifications
Post by: 5thAve on March 29, 2012, 02:37:10 PM
Ain't nothing that time and money can't solve, right? Anyway, looks like I'm going to invest in a die grinder and start experimenting.

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Title: Re: Pls help: cylinder modifications
Post by: burning1 on March 30, 2012, 02:28:05 PM
When I looked into this, flexshaft tool was by far the best bet. You can get a decent die grinder for ~$100... Should also get a router speed controller though, since most of the inexpensive die grinders don't have adjustable speed.

If you have a big source of air, a pnumatic die grinder is really really good.