Carburetion and jet sizes for restrictor plate racing
Carburetion and jet sizes for restrictor plate racing
(OP)
I am trying to make a single cylinder Briggs & Stratton Animal racing engine compete in a restrictor plate class for my 10 year old son. The engine is running rich and sounds flat when he is on the track. The main jet in the Walbro PZ22 carb measures 0.96 mm in diameter. The resrictor plate has three 0.225 inch diameter holes. I have been unable to locate any information regarding what the recommended jet size should be to make the engine run well with this restrictor.





RE: Carburetion and jet sizes for restrictor plate racing
I'd confirm the float height is correct and the air cleaner is in good condition and not over oiled and then install a slightly smaller main jet. I'd go by jet number, not measured size, altho it is a good idea to confirm approximate physical jet sizes just in case someone has been in there with numbr drills or jet reamers.
As a quick check restiricting the carb bowl vent makes the carb go lean. If the engine perks right up it suggests leaner is the way to go.
http://wem.walbro.com/distributors/servicemanuals/...
RE: Carburetion and jet sizes for restrictor plate racing
RE: Carburetion and jet sizes for restrictor plate racing
RE: Carburetion and jet sizes for restrictor plate racing
RE: Carburetion and jet sizes for restrictor plate racing
RE: Carburetion and jet sizes for restrictor plate racing
RE: Carburetion and jet sizes for restrictor plate racing
RE: Carburetion and jet sizes for restrictor plate racing