You do not want to switch back and forth between a Mikuni and Weber for emmissions. The vapor lock can be caused by a bad Bowl Vent Valve. The mikuni is heated by coolant from the radiator. When you turn off the truck the gas in the bowl likes to evaporate to the charcoal canister via the bowl vent valve. If it can't do this the gas goes into the engine causing hard starts and bad fuel economy.

Bottom line is the truck is 20 years old and carb needs attention. You can go hit or miss with a rebuilt from FCproducts for around $400 or the expert in Los Angeles will run about $500.

Before you do anything read the Carb section in the FAQ, sometimes it's not the carb but the sensors. Run some fuel system cleaner thru your next few tanks.

As far as HP or Torque <img src="/forums/images/graemlins/lol.gif" alt="" /> Everyone who says they see a performance increase is comparing there worn out mikuni to a new weber. A carb does one thing only, mix fuel and air at 14 to one ratio. My rebuilt Mikuni will push my brick on wheels past 85 mph on 31's with pedal left over.

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