Detroit fuel consumption As a general rule, you can calculate fuel burn on a Detroit 2 cycle with the following formula. 8ozs per hour per HP twin 450's = 900hp X 8ozs or 7200 ozs/hour at 100%. Divide by 128ozs. to change to gallons = 56.25 GPH at 100%. I believe you will find your "normal" RPM and cruise speed will be closer to 65 or 70% not 85% so your fuel burn should be about 36 1/2 GPH. No matter what a lot of Detroit people tell you, these motors should not be run close to max. RPM. Typically, a 2300-2350 RPM motor is happiest and will live a lot longer running at 1900-2000 RPM than it will at 2050+. Also, make sure your motors will turn up close to the reccommended maximum RPM with a full load. If they don't, find out why. Without going into a lengthy rant, if the engines are running properly, with 100% no load RPM, and the bottom is clean, your props will be the first place to look for more or fewer RPM. Capt. Bill Hadley United Yacht Sales
Hi Bill, Welcome aboard. Thanks for posting an informative answer. I might be filling-up in your neck of the woods soon. I've been cave hunting in Jupiter/Tequesta for a few weeks. I've always considered myself a fortunate person, but man... I feel like I'm on welfare with the prices of these homes! Look forward to seeing you online (or around town!)