Can someone help me out

[Huskytx300]

So I have an 89 chevy ck1500 sport with a 350.  When I drive it and it shifts into 2nd gear if I give it less than 1/4 throttle it does fine but when I give it more than 1/4 it just bogs down and has no go until I let of the gas.  I've changed the fuel filter recently and have used some seafoam products to.  It needs a new water pump and it gets hot pretty fast I just didn't know if something like that would have to do anything with the problem I'm having.  And I didn't really know if its just going into limp mode or something.