selection is pure personal preference.
TBI - common as the hairs on a dog. and a factory piece. thats not a bad thing on either count. common means they are plentiful and cheap to get, and there are lots of spare parts available. Its also just a plane good system. more upper rpm potential because of the intake design, fewer parts to fail, to me means more reliable.
MPFI - cool...... but necessary? typically its an aftermarket system, which im not a huge fan of, id rather stick with a factory setup. with parts support. factory parts tend to be supported down the road for decades, an aftermarket setup.... who knows how long they will be in business, and if they will be supported after they close.
TPI - in my opinion, which isnt that humble, the TPI engines were the best (gasoline) truck engine ever made. I say that having one installed in my 1989 IROC-Z. The longgggg runner design gives awesome low end torque, but still supports a good level of hp as well. If i werent married to diesel, and heck, i might even have an affair with this, a vortec headed TPI 383 or 408 small block would be sex between the fenders of a blazer. The TPI comes in three different flavors. up to 88 they had the 9th cold start injector, which i would personally avoid. 1989 is the last year of the MAF system, which is pretty much self adjusting and tuning, and for 1990-1992 it was a speed density system, which is a great system, but to tune it you either need to use a laptop, or have a custom chip burned for your application.
