89 Comanche troubles

I have an 89 2wd Comanche and I have had it for some time ran it, when I bought this one it didn't run right but ran an so I drove it solid. It did run at idle an at wot ran great anything in between an it would spit and sputter. Anger a year the slow oil leak was the death of that block so I when tout an got a 96 block changed everything over an installed after fighting over installing the distributer it will crank and run now at idle speed, but will not accelerate above 1200 rpm anytime the throttle is touched it dies out an sputters checked everything

Plz help