I just want to know what is better in a nitro. ABC design or ringed?

I have never seen a ringed nitro car or truck engine. If you are talking about an airplane engine they only turn about 1/3 the RPM a car or truck engine turns.

The engine that I have is an ABN construction but near the top of the piston there is a groove with a brass looking ring inside it. I know its not an airplane engine. Its a race engine and it turns 43000 rpm's. Im stumped. The company that makes this one also has a high end .12 race engine for about $500. This one goes for about 250. Not that it matters but just to show its not a cheap engine. I would take a picture of it but I dont want to take it apart.

car motors have compression grooved machined into the pistons, its basically a cut usually up the top of the piston head to help hold in the compression

What engine do you have? I seriously dough it is a ringed engine! ABN is not as good as ABC! Yes most engines have a grove near the top of the piston to help hold oil to make it seal better. Might just be oil in the grove.

Nope. Its a ring. Its a Peak Racing / Team Orion Diablo.

I always thought nicasil plated was better. Here is what I have read. The motor is nicasil not nickel plated.

Most nitro rc engines are of the "ABC" type design. The ABC stands for ALUMINUM BRASS CHROME. This means that the piston is aluminum, the cylinder liner is brass, and the internal wear surface of the cylinder is plated with chrome. This hard chrome plating offers a much better wear surface than the soft brass underneath, and helps to prolong engine life. Sometimes, you will see an ABN engine. Usually the N stands for NICKEL plating in the cylinder liner which is cheaper and less durable. However, occasionally expensive, high end rc nitro engines will have an "ABN" design where the N stands for NICASIL plated cylinder sleeve. This is a premium plating found on only a very few very expensive engines because it offers even better wear resistance than chrome in nitro rc engines. This nicasil plating comes at additional expense. By far, the majority of good rc nitro engines utilize ABC technology with excellent results and long life potential.

ok. I found some info about the ring. HPI also makes a motor that has an oil ring on an abc type piston. Its a nitro star 25. Picco and ofna also make some motors that are ringed. Its just an oil ring not a compression ring.

I looked on there web site and could not find anything about a ringed engine. Please direct me to this information where they show a ringed engine.

Yes I know ABC is much better and is why 90% plus engines manufactured use it. Nickel is just cheaper as stated in you above listing. I have run both and from experience know ABC is better.

Please post links. I do believe you will find that they are just a grove in the piston like I stated above. I owned a HPI nitro star 25 and it only has the grove in the piston like I stated.

Now that I am looking at it it just may be a groove. Could the piston be made of brass and I am seeing the machined recess which makes it look like a ring?

Nickel is different than nikasil plating. Nicasil is said to be much stronger than chrome and nickel is the weakest of them all.

What fuel are you running? By chance Sidewinder? The reason they call it an oil ring, which is the grove in the piston, holds oil to make a better seal like I said above. I have been a motorcycle mechinec and machinist for over 35 years.

I think thats what it is. I can stick a peice of paper into the groove.

Nicasil is nickel! Look at 90% of the top made engines like RB, Novarossi OS high end engines and all of them use ABC. Why do you think this is?

No nickel is different from nikasil. Nikasil is nickel silicone carbide. Much harder than just nickel. Alot of car manufactures use nikasil. Like BMW and Toyota. Im a certified Toyota tech and I know nickel and nikasil is different. The reason why not alot of higher end engines dont use it is because its expensive. Nickel is the cheapest and weakest. ABC is very strong but also cheap to do unlike Nikasil.