Any thoughts on this engine issue

DFX 340 Duster said
I agree that you seemed to have done all of the basic and easy stuff. Last easy thing would be to check the vacuum hose connection to the correct port (I am sure that you did this on the carb swap) and inspect the valve springs for integrity.

Then it is pulling the intake and check the condition of the cam and lifters. Check the distributor bushing/gear as suggested above.

Next, pull the timing chain cover and remove the cam and inspect for corrosion of the bearings.

Then, pull the heads and inspect the cylinder walls for pitting.

Finally, pull the crank and pistons. Hot tank the block, and reassemble with new rings and bearings.

That the same basic advice an engine builder told... Tear it down and eventually you'll figure it out.... Well that is way out of my talent level, hence Y I paid to have this done for me years ago... Its just a shame like most of us it took till now to get it running... But you have to jump when you have the money in this hobby or they never end up finished.

I just can't see why any of this would be an issue since the motor and the bucking goes away when the motor is under throttle??