Early mods were a Haigh tailwheel, and Haigh header tank, then four-aileron Sparcraft wings, braced horizontal stabilizer and reinforced carrythrough. The Sparcraft wings were later modified by squaring off the tips and extending the ailerons. After repeated ridicule at US contests, RV3 wheelpants were finally installed (yo plane ain't got no pants, boy!), and the fabric covering on the gearlegs replaced with airfoil shaped aluminum. A catastrophic aileron linkage failure resulting in a three-wing landing (bottom left wing main spar sheared off at the fuselage attach, right through both metal straps) which led to two new bottom wings and yet another set of ailerons. By now the wings had wood leading edges, reinforced attach points, and boxed bays under the I-struts.
The electrical system started out as a full battery/generator/starter. All Delco-Remy and HEAVY. At first everything was removed and the plane was started by swinging the prop. Then a B&C starter was installed with a shaved ring gear and the airplane was started from an APU plug. A quick removable battery with enough cabling to reach the APU plug from the ground came next. Seemed like the best of all worlds, easy ferry flying with the battery, then removing the battery at the contest and using it to start the plane on the flight line.
The engine was an O-360 A1A, hollow crank with lightening holes, Bendix fuel injection. In the summer of 86 it sheared a spigot gear bolt in the accessory case and ended up with a major overhaul, with the case shaved for higher compression. The stock exhaust was replaced with a Sky Dynamics stainless crossover 2-2. Powerful and reliable it needed nothing else for 19 years.
Along the way it flew probably 50 Unlimited Contests (at least one a year) from Winnipeg to southern California, numerous airshows, plus the World Aerobatic Championships in 1988 at Red Deer, Alberta. At 30 litres per hour cruise, and 60 litres per hour full throttle aerobatics, it's been a cheap thrill. Short 15' wingspan keeps the hangar cheap too.
Here's the big rudder version from the late 80's
