I think the FI head is a little more efficient; so, peak numbers of the FI motor may be a little higher. I think Brad addresses it somewhere on the site. The bottom line is that Brad's info should give you an idea of the % of increase across the RPM range. Peck around on his sight as there is some great technical information that is backed up with dyno charts. One thing I've noticed is that some of the mods we (Ducatisti) make as "gospel" don't seem to generate substantial "quantifiable" gains.