CarlsonMotorsports
Site Supporter
Thanks for that, I was speaking about a gas animal, I guess they don't run those anymore. I'm unsure what you meant by when you said
"The percentage change in area will be even greater."
I'm interested in the reasoning for increasing the the big jet by 100% but not the low-speed jet. I don't race 4 cycles, no experience, looking to learn.
No one runs gas animals that I am aware of, there may be a few Baker Pro-Gas engines still competing.
The Briggs LO206 runs on gas (animal platform engine with a sealed bottom end and spec jetting - ie cannot be changed legally.)
I don't understand your comment on "increasing the big jet by 100%."
If this fellow's engine is hitting a "barrier" at peak rpm, that could be an indication that it is overly rich on the main. It will wet foul the spark plug and, if bad enough, shut the engine completely off for 1 second (only at peak rpm.)
Changing the low speed jetting will do nothing to fix this problem.
My suggestion is that he go down .001 or .002" on the main jet to see if this alleviates the "barrier" problem.
We have no idea what size main jet the OP is using. My suggestion of a .052" is a good starting point for his alcohol purple restrictor plate animal engine.