As a guy with many many trucks i can tell you that my 85 with a 350 is much less powerful than my 93 was when its 350 was stock..It still has loads of power sporting a 4 spd manual with 4.11 gears and my 93 better known as bubba now with 4 spd auto and a 3.42 rear..its hard to compare them side by side due to the diffrent trans/gearing andsizes//33'* againts'36'* yet if you compare the engines i would take a 1993 350 (lo5) over a 1985 (LM1) the LO5 sports stock 210 hp and 300 tq and in my truck got 18-19 hwy
the LM1 sports 190 hp and around 280- 290 tq..and being carberatued mileage is much less.If i were you id go get a LO5 out of a 1993 plus silverado with harness and computer and swap that in you will be pleased..
2000 Suburban 3" lift and some power mods..The daily
06 impala SS CAI,Exhaust,pirellies the other daily
86 camaro Far from stock......The hot rod
1992 camaro RS 25th anv 350 5 spd..The cruiser