Well said. I agree.. other than the low idle bog.. it runs perfectly if idle is 1500. I think CV carb does a good job otherwise.

 

You're pretty close I think. A notch too rich on the needle and turn down the airscrew to 2.5 is my guess. I do the airscrew this way:
Turn up until standard idle begins to rise, turn down until idle barely starts to stumble, half way between is the baseline. If it's stumbling at low rpm throttle chop like that, it's rich on the low speed circuits IMO. Also, the stock carb does need the slide drilled, as that is also a low rpm mod.
FWIW, the powerbomb showed a power loss on the 351 dyno runs.

 

We developed my set up for 351 #3 using the slide modified stock carb and 1/2" drilled stock exhaust and I was always happy with that combination. The lowend and the midrange pull of the 351 is awesome. It really delivers the "tractor" power, and for some, that makes the best trail riding engine.

 

351 changes the bike from a weed whacker to a thumper!

Slide carb makes it a thumper with attitude.

David

 

Hard to believe the powerbomb would result in a decrease in power with the right silencer, jetting, airbox, filter.. something must have been off with that dyno result.. I love the megabomb (megabomb is bigger than powerbomb) and the low end torque is awesome with that pipe