oztrack

When a car has been modded with an intake and better headers and the mod results in a gain for 25rwhp. How much more fuel is usually needed to be added to the VE table in the tune (speed density)? Or putting it another way how much does the AFRs with the original tune need to be changed.

I have needed to change my cars tune by adding 4% across the whole table from a change to long tube 1"7/8 headers from short tube 1"5/8 and am about to install a FAST manifold and a 90mm. The car has run 11.414/118.6mph and im now chasing 11.0-11.1