Go .21 head button needing turned down to set squish

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Davidkrienke

Well-Known Member
Joined
Jul 7, 2018
Messages
405
Would anyone be able to help me with a go.21 7 port head button. Its squish is .0017 and I need to get it to .0006 to .0008
 

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I am an idiot . I meant its at .017 and I need to get it to .008 I have been adding one too many zeros . I am just always a mess......
I found this head online for the Novarossi Plus 21-4c engine does anyone know if this will fit the Go sleeve?
 

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The head changes on long and short stroke engines.

Brad
I believe that the Go must be longer stroke because all my rossi r21 heads are larger diameter button when I measured both of Them . The head abovevpic is for the Novarossi Plus 21-4c engine it says.. Wonder if it is a long stroke ?
 
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I would not be a big deal to have someone with a lathe machine it down .015 and then you could shim it up.

Brad
Yeah i just don't know anyone to turn it for me . I need a Os xz head turned down a little too. Maybe someone on here can turn it for me is what I am hoping.
 
I sent you a couple pictures. It is from my Doubletime address. Here they are as well in case you don't get them there.
 

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I think that Nova head button you posted fits an XL Stroke Nova 21 Engine? I could be mistaken though? As previously mentioned, finding someone to machine that shoulder down on your existing head button, then use 1 or 2 shims to set the clearance to 0.008” would be the way to go. You might end up with the same issue if you buy a new button & find it has too much clearance as well.
 
I picked up 3 of these alpha 21 car engine head buttons they were only 3 dollars a pc so i grabbed all of them to mess with . They fit fine and gave the engine .008 squish but I notice that the bowl volume seems really large in these. I was reading that the car engines sometimes have too large of bowl volume. Is this going to make the engine not perform correctly? I am running 30 percent nitro. I was reading posts on bowl volume that .16 to .18cc is a good number for high nitro . What cc would I want for 30 percent nitro? . edit I measured the volume with water and the bubble full on the new head is. 16cc it looks like . so maybe it will be ok. unsure why the standard plug head looks so small.
 

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