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mon-thurs 9-5 cst
This jet is for the Tillotson PK-1 clone carburetors. Not guaranteed to fit other clone carburetors. If you are using the Ruixing clone carburetors they will use a different main jet.
For Most Engines Running Gas Main Jets range from .034-.038
If you are tuning your carburetor and it starts to break-up and crackle it’s lean add more main jet. Or if goes flat on top-end this could be lean and/or your cam can no longer make power at the rpm you are tuning.
If the engine hits a wall on the top end, acting like you hit the kit switch and bogs its rich go down on the main jet.
There can also be other reasons for carburetor tuning problems from ignition coils failing, coil gap being set incorrectly or fuel system problems such as fuel tank not venting or fuel pump failing or not efficient enough to race engines. Before you start tuning make sure you don’t have another issue.