whats the difference between a ringed and non-ringed engine?

whats better?

A ringed engine has a steel ring making the contact with the cylinder .
A non-ringed engine has the piston making directo contact with the cylinder.

That's a good answer.

As for what's better, unless you are competing in something that requires the last little bit of power out of your engine, it doesn't matter, neither is better than the other.

That's not to say they aren't different, and that there aren't different "care and feeding" procedures for the different types that help your engine live longer. Also, note that there are actually several different styles of non-ringed engine. Most are ABC/N, but some (such as norvell and some Fox and K&B engines) are non-ringed but not ABC/N.

what is ABC and ABN??

what does it mean?

ABC - Aluminum, Brass, Chrome
ABN - Aluminum, Brass, Nickle

An ABC/N engine has an Aluminum piston that rides in a Chromed(Nickle plated) Brass liner. The liner expands faster than the piston, creating the optimum compression seal.

and what about ABL?

Where do you see ABL?

Check out Kyosho's glossary of airplane terms for such things as ABC, ABN, ABL and a host of other acronyms we are bombarded with in this hobby:

http://www.kyosho.com/glossary.html

Jesse

Here's ABL's homepage. Inquiring minds want to know right? [link=http://www.abl.com]Here is ABL's home page! Click This![/link]

From reading the Kyosho site, ABL would be the hokus-pokus OS came up with after their big black eye from their ABN engines that started pealing their liners. Early FX line engines had a real problem when overheated, the plating on the liner could flake off. A bad thing. It's apparently been fixed in the current FX engines.

For obvious reasons, I personally won't buy a used FX line engine (unless I know the owner, and the age of the engine), because as far as I know, there's no way to tell if it will have the liner problem or not.

In actual use, ABC, ABN, and OS's ABL are all the same thing.

Sounds like ABN is more of a marketing thing than a engineering thing lol.

I don't know enough materials engineering to know if there is an advantage to using nickle over chrome. I've always been under the impression that the guys who really KNOW engines prefer chrome and think the use of nickle is more of a cost savings thing than a real improvement in engine design. As I understand it, chrome is harder than nickle, and therefore wears better. However, like I said, I really don't know for sure, I could be way off here. I've never heard someone from OS (or otherwise "in the know") explain why they use nickle while everyone else uses chrome. It's a mystery. But the good news is that it really doesn't seem to matter in actual use. I happen to like OS engines, though I think they are bit over-priced.