[49studebaker]

I can tell you that the 96 & 97's (maybe all of them, I just know that my friends and coworkers own a few of these)have had problems with intake manifold leaks due to the fact they have less bolts holding them down than the previous small blocks. Fuel pumps seem to last about 90,000 miles or less(fuel pumps for them are also more expensive than for our TBI's). But all in all, they will have about 70 more hp than your Blazer. I haven't heard of them getting much better mileage than my 95. I'd still buy one.