carb into FI engine swap...vroom vroom but no zoom zoom

hello , i just joined and hope someone out there far more knowledgable than me can help...i have a rustfree 91 FI b2200 that cracked the block, my cousin had a rusted out 89 truck with the carbuerated engine which he donated and installed in my truck...he did the swap in his garage and the job went smooth...the truck idles well and runs smooth but has no power on hills or under load...he thought there might be an issue with the electronic in-tank fuel pump of the FI engine (compared to the mechanical fuel pump on the carbuerated engine)shooting too much pressure into the carb and the extra fuel was causing the catalytic converter to basically clog and restrict the engines power..does this sound possible and can i just disconnect the electronic pump and solve the problem...any ideas/suggestions would help...thanks

The pressure differences are massive I'm surprised it runs much at all! lol.
You might be randomly lucky and you have a gummy fuel filter creating a lot of back pressure which has opened your bypass valve.
Do you have a regulator somewhere in the mix?
If you have too much fuel you should have black smoke too, should be able to smell her running rich
If you can test how much pressure you're getting that'd be a good start.

Did you guys swap the computers and everything over? (probably)

How long has it been since you've done the swap?

Anywho, well done on swapping the engines over!
Always a worthy effort. (well... you went to a lower hp carb version but still... beats a broken engine right?)

thanks for the tips...i too am surprised it runs and idles so well, the relative who did the swap moved so he can only guess over the phone...i found a local shop that is willing to look it over, i'll suggest the things you mention...there is no smoke at all at idle...i wasn;t sure if disconnection the electronic fuel pump would allow fuel to still flow thru or without power to the pump it would create a bockage...i'll update as i learn more...thanks