Engine comparison....

[Albert]

Is there any comparison available for two and 4 cycle engines, where the size in one is compared to the other(s)?
Really, what would be useful would be a "pulling power" of the engine comparison... what with those hp, bhp, hps, etc!!!!!
Albert

[CDNshy_guy]

If you go to the Norvel web site you can get that info.
they have wav files to show you what your engine should/shouldn't sound like.

[Dave Robelen]

Hello Albert,
I have not seen a single site that gives all of the info you are asking for. In general, the folks who write competition rules figure that the 4 cycle engine is about 60% as powerful as a 2 cycle of similar displacement. There have been many engine reviews of both types in past issues of the model magazines that give detailed performance information on both types.
The two cycle engine has always been the favorite when high RPM and peak horsepower are the priority. With few exceptions in engines under .90 in.cu. the two cycle engines need smaller props to develop their peak power. They also are the most difficult to run quietly.
The four cycle engines are highly favored when there is a need to pull a large prop at lower RPM. This ability to run strong on large propellers makes them very effective at pulling heavy models as often seen in scale models. The four cycle engines also have a more pleasant sound and are easier to run quietly at fields where noise is a problem.
Regards, Dave Robelen