View Single Post
Old 09-28-2020, 01:28 PM
  #6  
Corndog38
Senior Member
 
Join Date: Jun 2014
Location: Middle Sound, NC
Posts: 8,925
Received 1,713 Likes on 1,098 Posts
Default

Gas engines make about 10-12hp for every gph they burn. Two strokes a bit worse, four strokes a bit better. This only applies to mid-upper power settings. At low power or near idle the burn rate per hp is much worse. Diesels are 16-20hp per gph.

To the OP's question, with a 15hp at cruise power (not full power) expect 1-1.5 gph.