Is a 4.6 v8 enough in a full size F-150

[buickanddeere]

Are you trying to say that people put too much emphasis on torque?

The object is to perform work. Torque is not measurement of work . Work is a function of force, distance and time.

 

[jejeosborne]

Never said or implied 4000rpm. You are comparing apples to oranges.
Look around for a manual trans in a light truck b.t.w.
Truck transmissions have a bull low 1st gear for easing heavy loads into motion.
On the same hill the truck and trailer 245HP engine will pull out and pass the otherwise identical 160HP or 215HP rig. The 245HP engine moves more air to burn more fuel to make more power to perform more work.

Only when the 245 hp engine is operating at the proper rpm to produce that HP. That is what he was getting at. For another example, I have a souped up 250 cc motorcycle that makes 30 HP at 15,000 rpms but only 8 lb-ft of torque at 2000 rpms vs my Kubota making 30 HP at 2400 rpms and a whopping 55 lb-ft of torque at 2000 rpms. Which would you find easier to get a trailer rolling? Both can get the same work done because they are they same HP. Problem is and as was said, either need to slip the clutch or have some serious gearing on that motorcycle. So i guess i am one of those guys that say torque torque torque for the purposes of this forum.

 

[jejeosborne]

1000lb ft of torque at 1000rpm is a lousy performing engine.An engine with 500lb ft of torque at 4000rpm will walk all over your "torque" engine.
Do you understand the definition of work?

How about 500 lb-ft at 2000 rpms vs 1000 lb-ft at 1000 rpm. Which engine do you prefer? These engines would have the same HP. The higher torque engine would out accelerate the other because acceleration follows the torque curve.

 

[nahfwt]

The object is to perform work. Torque is not measurement of work . Work is a function of force, distance and time.

Um, what you are saying is the exact opposite of what you think you are saying.
Work = Force x Distance
Torque, by definition, is a measurement of work. That's why we are given torque measurements in the unit of Ft-lb
http://en.wikipedia.org/wiki/Torque

Power is the rate at which work is done
Power = Work/time
The common unit of power is the watt.
We are given the power measurements for an engine in horsepower (a unit of power), which is computed based on the torque curve.
This is why horsepower numbers can be misleading.
http://en.wikipedia.org/wiki/Power_(physics)

 

[slowzuki]

Sigh. Torque is not a unit of work. It is rotational force. Please would they start teaching this. Folks if you take a torque wrench put it on a bolt and hang a weight on the handle, if it doesn't move there is no work being done, force only. Its a rotating system not linear, the units get a bit screwy.


To the OP's question, inlaws towed several years a 6000 lb camper with a 2004 4.6 F150 worked great. I've borrowed it several times towing about the same. Their new truck is a 5.4 and they moved up to an 8000 lb 8 ft wide camper. Tows even better, father in law complaining that at 70 mph the gas mileage isn't very good. Not bad at 55-60 mph. The old smaller camper would tow without downshifting on their normal 4 hr trip to where they camp, new big camper will knock it out of overdrive on the bigger hills.

 

[eventer79]

I did not really the other replies, but to OP, I will say no, don't do it. The 5.4L is worth it. All of my 1/2 ton size vehicles (I've had Chevys and Fords for personal vehicles) have had either the old Chevy 5.3 big block or the Ford 5.4L. Worth. It.

My personal truck is a diesel 3/4 ton (horse trailer) but my truck for my job is a 1/2 ton with a 4.8L V8. It suuuuuucks. It has no power and the hardest work it has to do is drive a lot of miles, tow 15' john boats, and winch stuff, boats, trucks, up and down river banks. You can feel the weight of the aluminum john boat even when there is nothing in it, it gets crappy gas mileage and it downshifts 2 gears in cruise control to go up mild hills on the interstate. It is a Chevy (I prefer Fords), but it's pretty and comfortable...and that's about all I like about it. It has been reliable, but I'm sure glad I'm not buying the gas. Drives me nuts, poor gutless thing.

For a personal vehicle, I would never EVER get a 1/2 ton with anything less than 5L in it.

 

[dodge man]

Yeah, torque is without a doubt NOT a unit of work, there is no motion involved. I had a couple of years worth of physics, statics, dynamics, structural analysis, and structural design where we studies the heck out of torque and moments. A unit of work would not be ft-lbs, but ft-lbs per second, where some unit of time is involved.

I like the example above comparing a motorcycle engine to a diesel engine. Same horsepower, but totally different torque curves.

 

[Egon]

Good rule of thumb: when buying a machine, whether truck, tractor, chainsaw, whatever, when you decide on the one you want, buy the next bigger one.

Might run out of product to buy!

 

[Egon]

( You are comparing apples to oranges. )

They have enough similarities to be able to compare them quite well!

 

[Egon]

A good way to put it is my 5600# 28 HP tractor will out pull a 280 HP equal weight pickup. Gearing is where it's at and how you take advantage of the available torque through the use of those gears.

Chris

This one may depend on the coefficient of friction!:thumbsup: