We aren't sure what we want to do to it just seeing if the amount of money that had to be put in to it to compete with 450s is worth it or just leave it the way it is and get an 87 to 92 lt250r.what would just a port job do.would that be with doing just that. 

Doing just a port job on a 85-86 will raise the power level a similar amount as just doing a port job on a 87 to 92. 

It will cost about the same to raise the power level of either engine to be competitive with the 450s.  Unfortunately there is not a Santa Clause, a Tooth fairy or one magic modification that will raise the AVERAGE power level of any of the 250 two strokes with the AVERAGE power level of a 450 with a few bolt-ons.