![]() As before, the IO-390, here as the EXP119 package, uses a front prop governor and inhales through a flat filter in the forward baffling. That it has a Mustang-esque bark is just a happy coincidence. Downstream is a new crossover exhaust system sized and shaped to preserve power. The duct was carefully modeled to preserve pressure recovery from the nose to the servo. Easy peasy.) That servo is fed by a new induction system including a K&N air filter in the pilot’s side forward baffle, just inside the inlet. (A reminder here that engines are air pumps, primarily the more you can stuff through them, the more fuel you can add to that-and the more power you get. ![]() Working with Airflow Performance, Van’s engineers spec’d a fuel servo sized for an IO-540 to ensure it would not create a flow restriction. So that’s where Van’s starts on the uprated RV-14, but it didn’t stop there. The Airflow Performance throttle body could feed an IO-540 (right). This firewall-forward package is based on the 215-hp IO-390-C with a substantially updated cooling and induction (left). Looks like your basic Lycoming IO-390, eh? Not so fast. In the real world, the delta between a nominal IO-390-A and a -C could be, indeed is likely to be, more than 5 hp. Lycoming has changed its methodology in the way it measures power, with the older engine falling into a “plus/minus” range of rated power, while the IO-390-C has to meet or exceed its rated power by a small amount. A 5-hp increase from colder induction alone sounds plausible, but there’s more at work here. ![]() In both iterations, the 390 has a forward-facing servo boss, and there are no carbureted versions available. This is the result of changing to a cold induction system it’s separate from the oil sump in the -C but integral to it in the -A. (I’ll refer to the RV-14 generically, as there’s little difference between the trigear -14A and the straight RV-14.) Engine Talkĭeveloped jointly by Van’s and Lycoming, this version of the IO-390 comes to the party rated at 215 hp, a nominal jump of 5 hp from the more common IO-390-A. Instead, it’s an exemplar of what you can do by holistically developing incremental improvements by the engine manufacturer and applying a far more thorough R&D approach than “see if it’ll fit on the nose.” With this program, based on the Lycoming IO-390-EXP119, Van’s not only embraced a lighter, more powerful engine but gave it a more efficient home in both the RV-14 and RV-14A. Most emphatically, this is not what this latest iteration of the Van’s RV-14A is all about. ![]() All until you have a machine that’s taken so far beyond its design point that you might as well have started with a clean sheet. (And there ends your monthly ration of overused aphorisms.) Power is speed and climb performance, but it can also be destabilizing and, past a certain point, starts making the machine worse-with higher fuel consumption comes the need to carry more fuel, which adds weight and puts demands on structure, in turn further increasing weight. In the world of homebuilt aircraft, usually more power is better than less, but it’s also true that power without control is just heat and noise. It’s said that power corrupts and absolute power corrupts absolutely. ![]()
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