it is prob an equilivent of a pa-50II, it should go 25-30 mph, stock mix is 25:1, pretty rich by todays standards but I use it. I don't know what size carb you have. But in the pa-50I vs pa-50II it does make a difference, I think (don't quote me) it is a 10mm vs a 12mm. Hope this helped a bit. Best of luck!