[Barry_R]

few ideas
You could advance the cam a few degrees (depending on where it's installed now).

Try adding some base timing and shorten the curve to compensate - this usually improves idle and low end.

As noted a surge or lumpiness at part throttle is often a fuel curve issue that can be tuned out.

I've tried a bazillion different intake inserts, stuffers, and spacers on the dyno. Most do nothing. A very few seem to help - but they're never predictable.