I have an echo 23.6 on a 1/4 Pup. I have tryed a 16-8 and an 18-8. With the 16-8 I get 6900 and 7lbs of thrust. With the 18-8 I get 5600 and 9lbs thrust. My question is am I going to hurt the engine running it at the lower rpm. I've adjusted the carb so that it's getting plenty of gas an it sounds good. I'll say here and now I am used to glow motors and how they wind out so the echo sounds a little luged down to my ear. I may try cutting down the 18-8 to 17 and see what i've got or go to a 18-6. Any help you can give me would be great. One other thing, The cowl on the pup is big so thats why I'm trying to go with the bigger props. Thanks, Randy

Dont worry you will not damage your motor Gas engins like to be lodet you may not get as must vertical with the big prop.