Upgrading stock 1971 318 heads

Took a 100 mile trip with the 302 heads and new manifolds and after all the effort it was definitely worth it. I know I have gained horsepower and low end for sure. I had to dial back my timing and reset my primaries fatter. Im guess being able to release more air quicker the motor needs more fuel in the mix. Also the idle sounds more aggressive and over all tone has gotten louder.
thanks for the help!