Depends on the type of dogfight, please specify, pretty please?

What I can say is that in terms of turn and burn the SE5a`s weight is greater than that of the N17, and the SE5a has a much thinner wing airfoil (I.e deliberatily sacrificing turning power for speed)
The N17 w/fuselage mounted Vickers (I.e, not the lighter Lewis w/fostermount British version) and its 110hp has around 0.20 hp per KG whereas the SE5 series has 0.23 to 0.27 (At best) hp per kg PLUS bigger size and wings that generates less lift than those of the N17.
Simply put, little weight+thicker airfoil= Better turning
Theres is no better tuning or modifications in existense other than shedding weight, I look at it the almost same way in motorsports, for example track days, amateur tuned lightweight tin cans beating sponsored cars with big HP figures every day, especially in tight corners.