is there a real noticeable difference in fuel economy between the 272 twin small block 350s and 242 single 7.4L??

if so, does anyone have approx. numbers?

thanks!

cruising speed, not much if any, WOT yes!

272 with 350's runs 58mph, my 88 242 had a 454/365 mg and ran a best of 59.9a

Regarding fuel economy...the BBC will run a bit harder than the twin SBC's in a cruise...using a bit more fuel. Running near the top or at WOT the twins will use 25% more fuel on the average...but remember...the 272 w/twins weighs about 1200 lbs more than the 242 and is quite a bit more boat. Sixteen cylinders are absolutely going to suck down more fuel and air than eight will.

Performance wise, a single BBC vs twin SBC's in a 272 is an easy call...twin SBC on top all day long. You have to build a very serious BBC to match up and if you put even a moderate amount of heat on twin SBC's...game over...real quick.again..the eight vs sixteen rule applies.

If you are running an inland lake it's not worth the difference to go for twins...more of a luxury. In the open ocean and offshore cruising...no contest...advantage 272 w/twins.

When I go in the ocean on friend's boats that have a single engine...I make DAMN sure the VHF is working and that my Sea Tow/Tow Boat account is current. When I look back and see only one prop trail...I feel like something's missing.

The 242 single 7.4l would use less fuel than 272 t350 but there are other issues in such a comparison. In single engine installs the BBC is more efficient than SBC. I don't have numbers at the moment but that is a fact.
Brunswick wants people to think otherwise because of trade-in sales.

272 vs. 242 is not an 'apples to apples' comparison as the engine set-ups are different as well as the boat sizes. From a cubic inch standpoint . . . 700 CI for the 272 with twins versus 454 CI for the 242.

If you are thinking (asking) that you will get similar fuel consumption on the 272 because of the SBC, that will not make up enough of the difference in the fact of 2 engines and a lot more boat.

I would expect about 50% more fuel consumption per hour or mile on the 272, but a whole lot more 'fun' for the $$$.