My first engine upgrade was to add a turbo to my 2.8L. I had it running for about a year at 5 psi of boost without problems but it was on a relatively low mileage engine. The next upgrade was an 3.4L engine replacement with Ross Forged pistons a turbo cam and a fresh rebuild with 10 psi of boost. Except for a lumpy idle that engine ran great but it was designed for boost. If your rebuild has hypereutectic or forged pistons I would say its going to work but if it has cast pistons then just keep the boost to 5 psi. That will still provide far better performance than stock. If you are concerned about knock, switch to the 85 ECM, add the knock sensor, ESC module wire it in and turn the switch on in the program for knock sensing.
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "