RE: Ace 4-120 engine
Hi Jim
Yes 15lbs is a bit much for the 90SP if you want speed. A 16x13 prop will give you more rpms and may improve the speed though.
Alternatively the 120SP is slightly more powerful (a couple of hundred rpm on similar size props) than the 90SP so may be a better choice. This is only 5.4mm longer to the prop driver than the 90SP, but does have a different bolt pattern. You can view these on the following link [link=http://www.rcvengines.com/sp_series_dimensions.htm]http://www.rcvengines.com/sp_series_dimensions.htm[/link]
We are in the process of developing a 120CD engine, however this is only on the drawing board at the moment.
You will be pleased to know that we are exhibiting in Chicago in October 06. Our engines should also be on sale at the Toledo show through Kondor models, however I am not sure if I will be on the stand or not yet.
Anyway, I hope this helps, please let me know if you have any further queries
Best regards
Laurenne