The Hispano-Suiza gave it a speed increase but the additional weight of that engine and its radiator/coolant reduced maneuverability, increased stall speeds, and limited the ceiling to 11,000 feet. The Belgian RE.8 conversions had similar results.
Unquestionably, THE resource standard for the Belgian Air Service is Walter Pieters' book The Belgian Air Service in the First World War https://www.amazon.com/Belgian-Air-Service-First-World/dp/1935881019
Can be pricey for some--depends on one's wallet--but it's hardcover, 722 pages, has over 1000 photographs (good size, not those postage stamp Osprey sizes), pilot biographies, sortie information for literally every day of the war, and I forget exactly but something like 80 color profiles. It's worth every cent for a lifetime of resource information.