Fit the intakes with oversized valves… Up from 1 7/8″ to 2 1/16″. You will need to readjust your main jetting when done.
Also consider running a hole saw thru your muffler to remove the baffles and spreading the rear exhaust tip to allow a free’er flowing exhaust..
Also consider having the cylinder deck height reduced by milling the cylinder gasket surface or the bottom of the flange surface… How much? The measured amount from the piston TDC to the head gasket surface… That will raise compression and greatly improve the “squish” area… You’ll love the increase in power.