A popular question in regards to the RV-12 with a Viking 130 is if you can make any "changes" to the design, such as opting for a superior engine. Well, here is the answer, directly from Van's web site.
"The FAA has evaluated the RV-12 kit and found it eligible for registration in the Experimental-Amateur Built (EAB) category. The airplane comes as an exceptionally professional kit. The kit is not much more expensive than similar kits from competitors. The recommended engine is very expensive, low on technology and low on power."
Viking believes that the RV-12, with an up to date, reasonably priced engine package is the number one package for anyone contemplating an aircraft build or completing or already started an RV-12 build. Several Viking 110 engines are flying and have been for 5 years now with hundreds of 130's.
Viking has all parts to complete an engine installation in a Van's Aircraft