Post by 90GTVert on Feb 15, 2010 21:03:34 GMT -5
**Some cylinder heads sold with 70cc big bore kits may not be exactly like the one that I have.**
Just for grins, I cc'd the 50 and 70cc heads to see how much difference there is. I got 5.3cc on the 70cc and 4.8cc on the 50cc, to make a .5cc difference. It isn't a huge difference, but it is a free compression increase. The 70cc head appears to be nothing more than a stock head with a little machine work done to make the combustion chamber 47mm in diameter.
Here's a fun fact for you... Minarelli heads share the smae bolt pattern as the 50cc GY6 or very close to it. The plexiglass piece I made to cc my minarelli worked just fine to do these heads.
Just for grins, I cc'd the 50 and 70cc heads to see how much difference there is. I got 5.3cc on the 70cc and 4.8cc on the 50cc, to make a .5cc difference. It isn't a huge difference, but it is a free compression increase. The 70cc head appears to be nothing more than a stock head with a little machine work done to make the combustion chamber 47mm in diameter.
Here's a fun fact for you... Minarelli heads share the smae bolt pattern as the 50cc GY6 or very close to it. The plexiglass piece I made to cc my minarelli worked just fine to do these heads.