Lots of good info (only a small portion quoted above) but misleading.

The new Dodge Hemi isn't a pent-roof. The combustion chamber volume is defined by two small spheres. The spherical cut-out centers lie on the valve stem center line cutting nicely into the valve seats. Pent-roof chambers have planer surfaces, not spherical cut-outs. The remainder of the combustion chamber is flat with the deck surface for adequate squish. The new Hemi spark plugs aren't centered, it's better with two plugs sandwiched near center, as close as the large opposing valves will allow.

A very sound design that makes torque down low and up high.

Take the new 300C Hemi, making 340 hp at 5,000 rpm and 390 ft lbs at 4000. Please tell me how the new 5.4L 3 valve is better than these rating numbers with all it's technology. The Hemi makes more specific torque & specific power than the 3 valve engine (by specific, I mean power and torque / displacement).

I fail to see why the 5.4L is better. Also, what do you mean by the "The new Ford three valve therefore has all the advantages of a Hemi or Pent Roof, but it's actually much cleaner, with the additional advantages of multi valves, and overhead cams"? Don't both engines meet federal mandated emission requirements? Do you know one is cleaner than the other? Do you think more wear items, higher friction, more parts to fail in the 3 valve design is a strength? Curious what your thoughts might be.

 

I think the Chrysler 300C and Dog Magnum versions of the hemi are better suited for a truck than what is in the Ram. The Ram's Hemi makes 15 less Torque at 200 more RPM's, and 5 more HP but at 400 more RPM's. It seems like they put the car motor in the truck and the truck motor in the car.
I would love to see how the 3V 5.4 does when it is mated with the 5-spd Trque Shift. I would bet the Hemi will be faster unless loads are up and over 10K lbs due to the Triton's lower torque curve. The Triton should require less downshifting when the grades get steeper since it will already be in it's powerband, where the Hemi needs the Revs. I'm not saying the Hemi is a crappy motor, it isn't. It's just misplaced. If the one in the Ram's had the lower powerband of the cars' motor's I think it'd be a haulin machine, but still not on the same level as the V-10, but that's a whole different class of motor, but until Dodge get their, 6.1 out, it's the best gasser that they've got. It'll get real interesting when Dodge does bring it out and Ford gets the 6.2.
Remember that these are actual owners rear wheel dyno's done at different times and places, so the total output isn't quite apples to apples. Also figure in that they weren't done in drive because of the Speed Limiter kicking in, so the max outputs are lower than they could be for both dynos. It does give a good picture of where the powerbands are, and the flattnes of the torque curves.
Hemi

Triton

 

Looks like the Hemi had a hiccup early on. Supposedly this is something else that's "cured" by clippng the tranny wire. Do you know what tranny this was bolted to? the manual versions do seem to offer a better than average improvement over an auto. Thanks for the info.

 

I believe that dip in the graph is a function of the stingy torque management, as you said. The computer in the Hemi retards the timing and backs off the power so that it doesn't spin the tires at the hit of the throttle. I've seen graphs where the wire was cut, and they don't display that dip. Problem is, the 04 and later Rams do not have the wire to cut so there is no way to bypass the Torque management.

I've noticed Nissan Titan's also seem to have the same characteristic.

 

Thank you for your details clarifications. I do think that the Ford multi valve motor is more advanced technology, with overhead cams, multi valves, variable cam timing, and air charge motion valves....ect. The fact that the truck 5.4 liter produces a bit less horse power per cubic inch, doesn't really reflect on the technology or the performance potential of the multi valve heads though. The new Mustang 4.6 liter V8 uses exactly the same heads, and exactly the same cams as the truck 5.4, but it produces in excess of 300HP on only 281 cubic inches. Here we see these heads producing about 1.07 HP per cubic inch, slightly more than the Hemi's 1.00HP/inch3. Of course a Mustang 281cid 3-valve isn't exactly a low RPM tourqe monster compared to the truck hemi, or the Ford truck 5.4 application though. It's only at 320 ft-lbs peak at a relatively high 4500 rPM, but it's still rather impressive, considering it's giving up 50-65 cubic inches, and some considerable crank throw. However the much larger Hemi produces it's peak tourqe at almost as high of RPM.

The 345 Hemi in the truck produces 380 ft-lbs at 4200 RPM. (I looked this stuff up) Indeed the Dodge produces it peak tourqe at the highest RPM of all the new gas truck motors. Even the Nissan 32 valve motor produces its peak tourqe some 600 RPMs lower. The smaller displacement Ford truck motor, produces it's peak tourqe some 500 RPM's lower than the Hemi, and the difference (at peak) is only 15ft-lbs. Indeed the Ford 5.4 3-valve matches the Chevy Vortec 6 liter in tourqe, Perhaps Ford had their eye on the wrong competitor and were a bit surprized by Dodge's and Nissan's efforts.

Don't get me wrong. I think the new Dodge "hemi" is a very cool and inovative motor, and a worthy competitor. I wouldn't mind having one, if money was no object and I could buy several vehicles. If I was to go retro, and choose a pushrod, 2-valve motor, I would certianly choose one over a GM Vortec pushrod V8.


Concerning, "seat of the pants feel", that is largely a matter of gear ratio and HP/lb ratio, given the new truck motors are relatively close matches in power. The new Ford f150 is somewhat handicapped by having to turn higher gears, and by the fact that Ford typically works a few hundred pounds more metal into their trucks, than their competitors do. Most new F-150's will come with 3:55 axle gears, and although the 3:73 is an option, it will be in the minority. However, the final gear isn't the big factor, but the gear ratios in the transmission. 1st gear on the Ford is 2.84, and second is 1:55. The Nissan has a 3.83 1st, and a 2.37 2nd, while the Dodge gets a 3.00 1st and 1.67 2nd. Moreover the Ford auto is only a 4-speed, while the Dodge and Nissan get five speed auto or a six speed auto. This means that when you get on it, and it shifts out of OD, the Ford has to lug it out at a 1:00 3rd gear. The Dodge has two overdrives, so it's passing gear is also 1.00, but it has a much lower 3.92 rear gear.

Given those minor handicapps, the fact that several F150 owners and test drivers are reporting the F150 to feel just as strong, or in some cases even stronger than the Hemi, tells me that the 3 valve motor is making more average low end tourqe under the curve through the first two or three thousand RPMs from idle, despite what it's peak number is.