Dustin2,
See the following link.
http://www.classicinlines.com/Dyno3.aspI think it's worth it based on these dyno tests.
The little 2v Weber progressive is a great little carb for power and gas mileage, and it looks like Langdon's has the carb and adapter new for about $100. A +5hp and +6ftlb rear wheel gain with the 2v-1v adapter. So that is about $17 per horsepower, for an easy swap with new parts that is hard to beat.
The 2v down to 1v does hurt things - - but it is a pretty good gain for a bolt-on, you don't have to remove the head and rework it. Later, if you pull the head and hog it out, you still have the carb so it's not money wasted.
