I'm in the market for an RV-10 and have run across a couple that claim 310 HP out of the Lycoming IO 540 engine. They were rebuilt (and mods made, I assume) by Performance Engines in La Verne California. The cimpany appears to be out of business, and I'm unable to gather any info on what was done to increase the stock HP from 260 to 310 HP. Concern is theeffect on TBO and abulity to get engine repaired orrebuilt if the mod are unkilnown and shop is no longer around to answer questions.