We make ball-bearing throttle shafts! Our carbs are fully re-plated, using the most expensive and durable process available. We don't plastic bead the bodies and sell them. We machine polish them to restore the factory shine. We make our own nozzles for closer tolerances and fix sticky pistons. Every part of the carb is treated like it is the most important part. Carbs and parts are covered by a 3 year warranty. If carb cleaner and silicone spray lube don't fix it, we will! Exchange and same day service standard (customer pays shipping). How many SU "rebuilders" engrave serial numbers on the throttle shafts? We do Datsun Z, Datsun Roadster 1500, 1600, 2L, SSS, GX, and Volvo HS6 carbs. They all get Roller Bearing Throttle Shafts.
Ztherapy also has a forum on our website here.