2.5 260 vs 2.5 280

[tjones2937]

Pros and Cons of one vs the other? Any preference? I know the 260 has a weak charging system and people recommend putting on a Simon alternator kit.

What else?

[Speed Jr.]

280 gets twice the fuel economy.......or it seems like it does.

[rev.ronnie]

280 gets twice the fuel economy.......or it seems like it does.

That's probably a pretty fair statement....

On our last river run, I burned around 30-35 gallons in around 70 miles...Totally worth it.

[tjones2937]

if switching from a 2.4 to a 2.5 280, do I need a new tuner and adaptor? not clear on what is better 1 piece or 2 piece.

[keane]

The 280 needs a 1 piece adapter, and it should be the 2.5 adapter. Or else you'll have a big mismatch between the block and the adapter. Some people hog out the adapter to match the 280, but you should really have the matching 2.5 adapter. It's even better if it is the 2.5 1 piece adapter with the 280 tuner, but you can get by without that specific tuner.

[PaulR]

280 gets twice the fuel economy.......or it seems like it does.

Do you think it's just the fuel curve in the ECU? I have a hard time believing the 280 electronics would make that big of difference??

[Tom Foley]

My Allison with an A - 48 box set at 98 gets 4 1/2 miles per gallon cruising at around 60 -65 with a 26 ET . Now the STV even with a set up digital box uses way more fuel due to the higher engine height etc . Both engines are 260 's , both charging systems are weak as well . Always fully charge your battery and if it's at all suspect , replace it with a hot one . Never been let down .

[Richard Earl]

I owned a 1994 260 hp 2.5. I agree on the alternator--once I got in the habit of putting it on the battery charger, before I wanted to use it, I didn't have any more dead battery problems. Also, it was easy to flood when it was warm. I heard that the later 280 hp models were easier to start when warm. I sold my boat, 18 ft. Seebold mod-V tunnel, with that engine in 2007 and boy do i miss it! Richard in Texas