I would agree with earlier post suggesting the fuel pump or gas filter could be your problem. But seeing how your issue is with a Weber carburetor at higher speeds I might suggest checking the accelerator pump on the Weber. It is a diaphragm that can dry out and get hard and crack. It is...
I have no problem saying they are talking about H & H. If you have a running H & H engine it leaks oil like crazy. If you have a running H & H engine it won't be running long. Their quality control and attention to detail is nonexistent. And on top of everything else they will lie to you...
Per Les Andrews Blue troubleshooting book on page 2-5 you should have the following readings:
Measure ohms from (+) terminal to (-) terminal - 1.6 to 1.8 ohms
Measure ohms from (+) terminal to center (high tension) 6.7K to 10K ohms
Measure ohms from (-) terminal to center (high tension) 6.7K...
Here is a link to FSI Distributor. They have the installation and timing instructions for 6 and 12 volt.
http://www.fsignitions.com/FSI_DISTRIBUTOR.html
Sorry forgot the link.
Randy