Superior, AC Aeronautical Unveil New Engine for Experimental Market
September 14, 2011 –Superior Air Parts Inc. and AC Aeronautical LTD used opening day at Reno to announce a brand new, Formula One-inspired engine for the high-end experimental aircraft market. The XP-408 Advanced Competition (AC) engine is based on Superior’s proven four-cylinder XP-360, to which AC Aeronautical added its racing-inspired upgrades to produce a 230-hp powerplant.
“The XP-408AC has been designed with safety as a priority, efficiency as a requirement, and performance as a positive result,” said Andrew Higgs, director and chief architect of the 408 program at AC Aeronautical. “Take (the XP-360’s) proven quality and durability and add our racing inspired upgrades and you get an engine that delivers 230 hp and can do it reliably for a long time.”
AC Aeronautical took many cues from the world of Formula One auto racing to develop the engine’s key components including the new crankshaft, connecting rods, pistons, and piston pins. The several advancements include:
- A revolutionary, dynamically balanced crankshaft designed to dampen firing order vibration and increase the engine stroke to 408 cubic inches. Reduced vibration minimizes engine component stress and helps maximize engine reliability and efficiency.
- New four-bolt connecting rods, which better distribute the clamping loads to help stop bearing distortion.
- New heavily bridged slipper-racing pistons significantly stiffer than standard pistons. The new design is also 42 percent lighter than stock pistons, with each piston set matched to within half a gram.
- Significant weight reduction in the crankshaft rotating assembly, resulting in a significant reduction in inertia with a corresponding reduction in the stress and vibration that is found in the traditional engine.
The main goal for the designers was to move as much weight from the reciprocating parts to the rotating parts to ultimately reduce engine stress and vibration. “During our testing, we found that even while producing its full 230 hp, the XP-408AC engine actually generates lower peak-to-peak stress levels than a similar specification 360 engine at a similar rpm setting,” Higgs said. “Even with this increase in performance we have less stress on the standard components and hence a larger safety margin.”
For more information on the XP-408AC, call 972-829-4635.