Ecomod my gx390

[oil pan 4]

I discover a timing hack for digital ignition engines.
Setting a big gap between the coil and magnet will advance the timing. I tried it and checked it with my timing light. I get 4 degrees of timing advance at 4,000rpm.

[oil pan 4]

New mod, I put a velocity stack on my gx390. Now it sputters and dies as soon as I touch the throttle.
I'll put the next size bigger jet and the next until it runs normal. I didn't think a velocity stack would make that big of a difference.

[oil pan 4]

With the stock intake it was running great with a #100 jet. Put the velocity stack on and it needed a #105 to kind of run. Today it was being needy and would throttle up without a little choke. Think it needs a #108.