Improving low end torque usually has a trade-off in decreased top end horsepower, and vice versa.
Very true in my experience, but if you study GM's records regarding the development of your particular engine, you might discover some of what it sounds like you want has been done already. I don't know about the 292, but it did happen for the 235. Not the breathing part, Shane. Some Chevy inline sixes aren't going to breathe much better than an asthmatic chain smoker in a Death Valley dust storm with a potato stuffed in his mouth, but you might discover some versions of your engine have answered the question of higher torque at lower rpms. They did this with the 235 in 1959...and it is interesting. Maximum torque increased to 217 at 2000 rpm where horsepower declined to 135 from 140, but max horsepower occurred at 4000 rpm. In 1956, max torque was 210 at 2400 rpm (~17% faster) and max horsepower was 140 but at a higher 4200 rpm. What changed? The camshaft changed, according to GM Heritage data. They were going for more economical power, so they changed the camshaft They changed from .400 lift on both intake and exhaust to one with .320 on intake and .328 on exhaust and also changed from 185 degrees duration to 174 degrees duration. So at 2000 rpm, you have all the torque you're going to get out of the stock 235. They left it this way until 1962.
