All Yami's leave alot! It goes back to the 76 SRX! The 440 lq was actually capable of almost 100hp from the dealer! Which was almost double most other 440's! There were alot of recalls and problems! Yami never took there engines out that far again! Thats why there is no Facotry Turbo!
I would not say they leave a lot, just enough so that you are not wrenching on the thing all the time. And that I why I drive a Yamaha. Reliability. Who wants a sled that is pushed past the limits and then is burning down on you.