Is it just new pistons and wrist pins? Yes, and maybe only pistons if you already have heavy wall pins and hardened cylinder bores. Lycoming recommends that if you have plain steel straight bore cylinders, on the 150HP engine, that you use a hardened barrel with choke for 160HP. That would be either nitrided, through hardened or plated cylinders. Lycoming stopped using plain steel straight bore cylinders on the low HP engine several years ago but if you have an engine from prior to that change, you might consider changing the cylinders as well. I have no experience with what the durability is, running plain steel with 160 Hp higher compression pistons.
what is the rough cost for this? depends on who does the work and whether you need just pistons or piston and piston pins and cylinders.
What are the gotchas? See above.
Can I get any more horsepower with additional simple upgrades? More take off RPM is simple way to increase rated power at take off or full throttle. More throttle in cruise at lower altitudes works too.
Good Luck and Merry Christmas,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at your own risk."
