My '99 K1500 has a 305 crate engine with approx. 25,000 miles. It seems to be running really rich. The exhaust smells really strong (stronger than my grandfather's 1995 C2500 with a TBI 350). It still has the catalytic converter and both upstream and downstream 02 sensors (no check engine light). I'm sure it's not supposed to be this rich. Plus, I've noticed that my fuel economy is dismal at best. I don't know what I need to do to improve this condition.
Also, a question for those of you still running a 305: What kinds of things have you done to improve power? My truck has the 4l60e and 3.73 gears. It accelerates ok on flat roads, but I have to give it a fair amount of throttle to keep it at 55 or above when going up hills. I didn't know if there were common upgrades that could boost power that also wouldn't break the bank. Thanks in advance.
Also, a question for those of you still running a 305: What kinds of things have you done to improve power? My truck has the 4l60e and 3.73 gears. It accelerates ok on flat roads, but I have to give it a fair amount of throttle to keep it at 55 or above when going up hills. I didn't know if there were common upgrades that could boost power that also wouldn't break the bank. Thanks in advance.