Years of experience of working on, modifying, and building factory Harley Davidson, S&S, Ultima, and other aftermarket engines, has given me an education on the likes, problems, and dis-likes of what's available.
I'd like to set the record straight on Ultima engines.
1- Ultima engines are NOT made in Korea.
2- Ultima castings USED to be cast in the same foundries that cast the factory Harley Davidson engine parts, and also the S&S engines in the USA.
3- Ultima now uses the same foundry that does the casting for BMW, Isuzu, KTM, Honda, and Rotax. the reason for the switch is because they now use a superior permanent mold process. The alloy used is also superior/harder than the standard of the industry.
4- All machine work on the castings are done in house in the USA.
5- Flywheels are made in the USA, with the same rods used by Darkhorse Crankworks, Rev Performance, T-man Performance, and others.
6- Bearings, all are made by the same manufacturers as the others use.
7- Pistons are Mahle with Mahle rings. The smaller displacement engines use Ross pistons with Hastings rings. USA again......
8- Valves are Ferrea, beehive springs are from Performance Spring, guides are AV&V(Canada).
9- Cometic supplies ALL the gaskets, and seals.
10- Cam cover(nosecone) factory Harley Davidson.
11- Billit rocker boxes, and oil pump are made in house.
Actually there's more parts manufactured in the good ole USA than most of the other manufacturers including Harley Davidson.
Some facts:
1- I've never seen or heard of a stud pullout of an Ultima case.
2- I've never seen an Ultima head crack.
3- Ultima heads flow very well.
4- Ultima engines make very good streetabl power
5- Engines are priced right.
6- I am in NO way affiliated or paid by Ultima.
Hope this clears up the "stories".

John