might need a new water pump?

[Hot-Dog]

my truck overheats if i run for a long period of time, just continually gets hotter, could easily overheat. started doing it after a night at the drag strip on the drive home it got to 250* so first thing i bough two fresh tstats, didnt help. i ran the hose down each cylender bank and through the radiator and nothing is plugged up. seems like theres not pressure in the system, watch the vid youl see what i mean.



if the pump is bad ( probably is, what else could it be?) can anyone make sense of all these options for me?

Auto Parts Giant - Discount Auto Part Online

first off is the delco 252 838 "water pump kit" basicaly the midsection of the pump with the gear bearing and impeller or does it not come with the impeller?

also there's 2 delco pumps listed, whats the difference?

and lastly, how about the cardone one for $104, cheap Chinese crap or what?

any help is appreciated.