I've looked at that engine a couple times, but economics always prevail. It's cheaper to put a new 350 crate engine in my truck than that V6. Though it would be cool to have one of the baddest 4.3's around.
Yep. that and SBCs are cheaper & easier to hotrod too. Nice thing about the 4.3 is the fact it's around 80 lbs lighter than the 350. The blazer will eventually get aa 350, but the next project I'm cooking up in the back of my mind when I have nothing better to do calls for a hotrodded 4.3 to save weight.
Displacement is really irrelevant to this argument. Really, what you want to look at is torque to weight ratio. Cause a 327 and a 400 probably weigh the same, more or less. Just like a 351 and a 302 probably do. And the torque you're looking at is usable torque, low RPM.