GPH comparison between IO and DD

pdmoyes 05-30-2004, 10:15 AM

What would similarly equipped boats (say 21ft. with 350 motor) use on gas between an DD and an IO? My thinking would be the DD would use less. What kind of gph does the 4.3 motor get on IO's?

(655mac) · (655mac) **Join Date: Jan 2004** 05-30-2004, 5:53 PM

I don't know what the numbers are but it seems like my DD uses just a little more gas than our old 4.3 IO. Not enough more to matter considering the huge gains in performance. The 4.3 had to work hard all the time where the V8 is never strained.

sunsetterlxi 05-30-2004, 6:09 PM

Actually, you would think the Direct Drive would use more. It has a static hull where as the I/O is trimmable and you can reduce the amount of the boat's running surface as you go faster.

(toyotafreak) · (toyotafreak) **Join Date: Sep 2003** 05-30-2004, 10:37 PM

Paul, GPH is one of many things to think of.

Your first question: a towboat 350 hull is way more wet and will burn more fuel per mph (my 300 HP only gets us 43 mph). Second question: don't even think of a V-6 on a boat bigger than 19ft even though they're making 'em pretty strong nowadays.

Towboats are not for everybody, but there's a lot more to ownership than GPH. Ride, layout, safety, maintenance and oh yeah, wake/towing.

Towboats are pimp, but they are a compromise.

(98_searay) · (98_searay) **Join Date: May 2004** 05-31-2004, 5:22 PM

a 4.3 v6 on 14gallon tank can take you 2 days with about 4-5 ppl all wakeboarding 2 WHOLE ****ing days trust me my friend has one

ilovetrains 06-01-2004, 10:35 AM

Well - my 20 ft I/O with a 350 uses burns about 20 gal on 6 hours mixed cruising and boarding.

My father in laws 18.5 I/O with a 3.0 4 banger does the same,but is slow as hell.

Meanwhile the MC 190 (DD of course)w/ 351 (go Ford) will use slightly more (25-30gal from the 40 tank)in the same time.

His neighbors V-drive malibu runs 30+ gals in the same time.

Even if you say the DD gets 15-20% worse, and the V gets 1/3 worse GPH, you are talking different worlds. People pay to ride the MC and Malibu by dropping 5's 10's and 20's in the cup holder on the way out for gas money.

ag4ever 06-01-2004, 10:58 AM

I tried wakeboarding behind my dad's outboard. Could not get me up. Did not have the power required. I kept asking for more till he had no more. I have never told my wife that in out SANTE. There is always more power than I need.BTW, I can ride and cruise all day on one tank (26 gal) if I keep the speeds reasonable. if I hot rod at full throttle, then I can see the gauge go down.