:santa: Hi Guys... this is a question for the people in the know. I bought a 4.6 V8 in my XLT and am aware that the 5.4 has about 60 more HP, now here's my question. Does that additional HP create more acceleration speed than a 4.6 or just more torque enabling the truck to maintain speeds pulling a grade say with a good size trailer. The reason I'm asking is because the quickness of my truck makes it difficult to imagine the larger V8 would be even a faster accelerating than what it already can do. thanks for any info. GG

 

In a regular cab short box like yours the 4.6 won't have a problem but once you start gettting into supercab's screw's and 4x4's the extra weight really taxes the 4.6. But yes, if you had the 4.6 in your truck right now it would accelerate much faster with the 5.4.

 

hey greggeo,

you kind of hit both factors without realizing it.

Torque gives acceleration, HP keeps you there.

Yes there is 60 more horses but there is also more torque in the 5.4.

In your truck I don't think the extra HP or torque will make your truck THAT much faster, but it would take that much more load to lose the acceleration on the larger engine.

 

I would take the 5.4 over the 4.6 any day. I have the 4.6 in my Lariat and the 5.4 in my Expy, and pull a 21 foot boat with them. I can say that the 5.4 does make a big difference, especially going up hills. The 4.6 barely holds the speed, but I can accelerate up the hill with the 5.4. The 5.4 also gets better mileage than the 4.6.

 

My ordered F150 is also a RC shortbed (SS, 2WD, XLT). I went with the 5.4 since MPG figures were the same for both. I don't need the larger engine. The upgrades and the stronger transmission sold me on going for it.

I agree with the other posts that a 4.6 should be just fine in a 2WD RC shortbed. IMHO the 5.4 should go into a 2WD long that's going to be "worked" as well as any 4WD, SC, or Screw.

Enjoy your truck! (It's nice!) I'll probably always wonder if I could've beat the MPG estimates by getting the standard engine.

:santa: Merry Christmas!

 

Yeah if two engines for the same vehicle have the same mileage rating the bigger engine will have better real world fuel economy the majority of the time because it does less work then the smaller engine.