90HSR406

i need some insight on what im doing wrong or overlooking. i have a 90 rs with a hsr'd 400 in place of the 305 tbi. when i did the swap i put a walbro 255 lph fuel pump in it. after about 8 mos the engine started to miss, spit, and sputter with any change in throttle after about a half an hour of driving. i checked the pressure and it wouldnt go any higher than 30 psi. so i removed and capped the return line to eliminate the regulator. it still wouldnt make it above 30 psi. so i changed the pump and the filter. the new pump made 43 psi, for about 6 months this time. the same syptoms came back. so i replaced the pump and filter aaagain. and here it is 6 months and a deployment to afghanistan later with the exact same problem. what am i doing wrong? is there something the tpi fuel system has that the tbi doesnt?

built91Z28

You might try just replacing the filter.

90HSR406

i'll try it. it cant hurt right? thanks