that just about says it all I need to know the exhaust port timing for stock e50 and any others would be helpfull
exhaust port timing
Re: exhaust port timing
on my metrakit 65cc cylinder the exhaust port is 28mm from the top of the cylinder. it is about 16mm deep and about 26mm wide. The 70cc tccd cylinder is about 26 mm from the top of the cylinder. Its about the same size port as the metra. The stock hi torque cylinder exhaust port is 35mm from the top of the cylinder and is very small.. I dont have a degree wheel printed out yet so I dont know if this will help. some of the degrees are on the wiki http://www.mopedarmy.com/wiki/Puch_Maxi_Cylinder_Information
Re: exhaust port timing
how do you figure out how much to open your port up? or how far to go?
Re: exhaust port timing
seems like a safe way to do it is look at a cylinder that performs really well and model your slow cylinder after it. You raise the exhaust ports and lower the intake for good power in high rpm range and less low rpm power if you have a complimentary expansion chamber for your new rpm range. If you over do it you will have less power no matter what pipe you use. Another more safe way to do it is use lots extra cylinder base gaskets to raise the exhaust port (and the whole cylinder) and trim the piston down on the intake side to lower the intake port. The only problem with that is you raise the transfers in the process limiting this method.
Re: exhaust port timing
Various stock puch top ends have different exhaust port timings. I have two hi-torque cylinders, one's got an exhaust port 31mm below the top, the other had one 35mm below. At least it did... before I ported it. Mwaha.
Re: exhaust port timing
thanks for the info all it would be really cool if I had degrees after TDC just when it opens
Re: exhaust port timing
Some of these have port timings in degrees before TDC, but they're also mostly kit cylinders and here is the link
http://www.mopedarmy.com/wiki/Puch_Maxi_Cylinder_Information
I do wish the korado cylinder was on that page.
Re: exhaust port timing
This pic might be a little big, but you can see the difference in what I did. 50cc
Re: exhaust port timing
That pic above, is of a Magnum High torque clyinder, with the angled exhaust. It is hooked up to a cut & welded Tecno boss. I raised the exhaust port some, so timming will need to be retarded, not advanced as some may think. It also has intake work done to accomidate the 17mm Bing with"S" intake and the spacer, which both have been opened also ;) Brent
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