The Ultimate Walbro Small-Block RC Carb is here (and suits some smaller big bores). Exclusive to TAYLOR RC, this is a custom modified and bored carb manufactured by Walbro in Japan for us.
 
Works superb on all 30.5-40cc High performance RC Engines. Really wakes up 32-34cc Reed/PP Engines and of course was purposely designed to compliment our 35cc Small Block.
 
The 1257 is the only Walbro Carb with custom factory Offset boring developed and tested by TAYLOR throughout the first half of 2022.
 
Base Carb settings: 
1 3/8 LOW and 2 HIGH 
 
Your final tune will depend on Elevation, fuel, humidity, engine specs, exhaust etc.
 
When designing and ordering this carb, we didnt hold back, we ticked every single option available and even added a custom offset over-boring developed to our requirements!  Flow bench tests have proved the venturi is still the limiting factor in an 1107 style choked carb, so why not leave the handy choke and open up the bottleneck!
 
This all means the WT1257 offers 7% more CFM (stat from Walbro) over the carbs using a 13.5mm venturi (1048/1107/1254 etc). And of course even more flow than carbs using a 12.7mm venturi (603/813/990/1242 etc).  As stated by Walbro this is the maximum
 
WT1257 Spec List:
Custom Bored Venturi by Walbro (equivalent 14mm Venturi)
Spiral Diaphragm
Teflon Gaskets (metering and pump)
Throttle Shaft Dust Seal upgrade
Anti-wear shaft washers
Ethanol Resistant Bulb
Tuning needle clamp
HD Bulb retaining plate
Other internal fueling, filtering, sealing and metering mods