Originally Posted by Peels
We recently bought a boat, and have been towing it with my 06 4.7.
Now, I am Coming from a nissan 4 cylinder(drove for 15 years), so I feel like the V8 does "just fine"
JUst NO oomph when accelerating at highway speed...maybe I expected too much?
Yes you could say that. These days with emission requirements the V8's are really toned down.
What size is the boat? If it's a aluminum fishing boat with a light trailer,
you shouldn't be seeing much difference in power between no tow and
towing, but a cabin cruiser cruiser with a class II? hitch adds weight
and chances are you are not getting into O/D that much, so if you are
towing the boat in 3rd gear on the automatic a lot, the gas mileage will not be that great..
Towing MPG is pretty dismal(12.5), but thats life really...
That isn't very good on flat ground. I can see if you were in the hills
and the transmission was dropping into 2nd and 3rd. What is the
Are there any tips/tricks to better make it NOTICEABLY better?
I was thinking one of those cold air intakes would help a bit, and a better flowin muffler....?
Id like more guts, but i wont trade towing MPG's for it...bad enough already LOL
To get more h/p out of that engine, you really need a different cams,
a performance cams actually and different manifolds. The HO version of that engine would be what you are probably seeking, but not sure about the gas mileage.
Here's all the extras on the 4.7L HO (High Output) V8...
The HO engine was discontinued in the Grand Cherokee at the end of the 2004 model year. The all-new 2005 model Grand Cherokee's offered the new 3.7 V6, the standard 4.7, the 5.7 Hemi and the new 6.1L Hemi SRT engines.
Starting at the end of the 2005 model year, the 4.7 HO engine became availble in the Dodge Dakota.
Quite a few Dodge truck owners have successfully installed the manifold and cams into their standard 4.7 engines without any major problems
Most have reported horsepower gains from 5% to 15%, varying at different RPM's.
Anyone interested in doing this upgrade or learning more about it should visit the message boards at DodgeDakotas.com and search through the HO related posts.
The Mopar Manifold/Cams kit is available from Multitronics ("Kolak")
Ok, putting aside the hundreds required to upgrade the standard 4.7 on the Dakota to get more power out of it with new manifolds and cams,
which is a BIG rebuild job as well.... what can be done with the standard mediocre factory 4.7 to get more "oomph out of it but retain the current fuel mileage.. (without towing stuff off course)
1. Install a K&N air filter (a better filter than the standard paper filter),
ok a cold air intake kit
2. Better plugs (platinum NGK)
3. Try a better grade of fuel (mid grade) midgrade has more octane than the
standard 85 octane fuel and should develop more power in the engine
While mid-grade may cost a few cents more, in fuel grades, you do get
what you pay for.
4. If you are going for a low restriction muffler though, as a certain amount of
backpressure is required in the exhaust and you still want to have
the cat on to pass emissions.
But the factory 4.7L is detuned on purpose, so even with all the above
you would only probably see a marginal improvement in power after
installing all the above..you really need to change the timing curves for
the ignition and injectors to get that extra power out of it.
5. If you don't live in the state of California, you could also consider installing a performance Chip upgrade
( like Jet Stage 2 performance module) or others
described on this board.
These are easily installed onto the PCM.
However with that extra performance, your MPG WILL also drop...it's the other side of the coin unfortunately. You mention that you are already in the high fuel consumption (12.5 mpg)category, so you don't want to drop too much below that
either when towing.