Genuine Walbro Aftermarket Pop-Off Spring for 990/1107 & Fujiwara 14mm/15mm Carbs

This Official Walbro Metering Spring is an Optional Upgrade tuning part designed to reduce pop-off pressure in all WT Carbs down to 15-16psi when checked with a Walbro Pop-Off Tester. Works as a perfect upgade on: WT-990 WT-1107 Fujiwara HP G350RC Carb kit with 15mm Venturi Fujiwara HP G320RC Carb kit with 14mm Venturi This reduced tension spring allows the carb to feed your engine fuel at an earlier stage in the throttle opening process as the spring "pops-off" sooner. This allows the inlet jet to open and you avoid the lean bog that often happens with Stock carbs on Tuned 32 Reed, 34cc, Taylor 35cc, OBR 34,35 38cc & FJ350RC Engines for example. Works very well when adding the upgraded Bonehead Carbon Reeds to your engine too. This is the stock supplied Walbro Upgrade as used by their R&D Dept in the 1242 and 1257 Upgrade carbs, best you can get.