I put one of these in my K5 about 3-4 years ago, and have never had a problem with it. it even survived being submarined. /forums/images/graemlins/whistling.gif I just flushed it out real good, filled it back up with oil, and it was good to go, been running fine ever since. and I don't know about in completely stock form, but with a good intake, carb, cam, and headers...mine makes plenty of power to push my blazer on 36's along just fine...oh and off-road. /forums/images/graemlins/thumb.gif