16.5 ohv lean when low idle, floods when high throttle

I have a couple of these OHV briggs motors about to be re-rebuilt and one race-modded. I do not wish to use the original carb if possible, as I find the fuel solenoid to be a horrid pain in my cheeks. On stock builds I generally just take the solenoid out, clip the plunger or file it down, and install a fuel shutoff valve. I am curious though, as my last time doing this created a really odd problem, one I'm not sure about. At low idle (using a gas pedal rig-up) it runs lean, almost too lean like it gets no fuel... but when throttle is pinned up to 3600 +/- rpm, it floods out... sometimes backfiring.

Is it possibly the carb being gunked up or do you all think it may be needing another valve adjustment? I usually check valve lash at every other oil change... but haven't in a while...

You can easily bypass the fuel solenoid with a 12v source and a switch. Thats what I did with the Rally.

oh, I already do that on the carbs that still have one. I guess I should word my question differently - on the last one I modded I seem to be starving it for fuel at low idle and flooding it at high idle... what might be causing it?

Probably just needs a good carb cleaning and some idle adjustments.

probably - I will get to that as soon as I can and see if it helps. If not, I'll go to a non-stock walbro carb on a cast intake with some beercan and copper spray gaskets lol