Hemi hype
Well when it was in the shop the new 2003 Hemi Quad Cabs were in and I decided that I might as well trade my 2001 Dodge Ram 2500 work truck in for a loaded 2003 Hemi Quad Cab 2500. When I took it for a test drive I noted a great exhaust sound, but was very disappointed with the auto trans. I decided that it was still much nicer than my old truck and decided to go ahead with the purchase.
Dodge touted the fact that the hemi got improved gas mileage. Well my old Dodge with the garbage 5.9L actually got a lot better gas mileage (and I know it wasn't all from going from standard to automatic). The hemi was averaging about 12 MPG, and I think the best I saw it do on the highway was 14 MPG driving like an old lady.
I never thought the hemi felt that fast, mainly due to the transmission. In the automatic equipped Hemi Ram, I couldn't even spin the tires. With 345 HP, that is pathetic!! I had read on a newsgroup or dodge board that they limited the power to the transmission because the transmission is not strong enough to handle the engine. Someone found out there is an extra wire that is run, and if they put a toggle on it, they can turn off the limiter (which voids warranty if Dodge finds out). Once this was done they could smoke the tires, but surmised that their trans probably won't last that long.
I thought the Hemi Ram 2500 was a poor towing vehicle also. When only towing around 3800 lbs., the hemi felt sluggish on back roads and inclines and it was hard to stay at the peak of the power. You really needed to rev the thing to get it to have some power. I felt like I had to really beat it up to get any performance out of it.
I kept the Hemi ram until I had about 15,000 miles on it. I was never really happy with it, mostly due to the transmission and partly due to the HP/Torque -> RPM characteristics. What finally was the last straw (I had experienced various issues with the truck throughout the 15,000 miles - though it was all covered under warranty) was when the oil pressure guage would read zero when starting it at random times. If I shut off the engine and turned it back on, the pressure would come back. After bringing it to the dealer and having the computer flashed, the problem did not go away. Soon after a tick developed in the engine bringing back memories of my 5.9L. At that point I figured it was time to get rid of it - and swore off Dodge in the process.
As far as the Hemi goes - I was not impressed. On paper it looks like the best truck out there. But after owning one, I can honestly say that I won't miss it. The only thing the hemi was really good at was exhibiting some speed (but it did not like it when you floored it WOT from a standstill, it actually ran better 3/4 of the way down). It's a mute point though - now it's been outclassed by the Nissan Titan in that area (Hemi 0-60 8 sec, Titan 0-60 in 7.7 sec or something like that).
Just my 2 cents!
Well I hate to say it, but right at the moment I'm driving a 2004 Buick LeSabre Limited that is completely loaded. It gets 30 MPG and is really a nice large sedan. It is a really nice ride and the first car I have owned in 10 years. The problem with it is it's going to depreciate quicker than dirt - so I may private sale it soon. But...
This weekend I'm going to be picking up a 1996 F150 XLT 4x4 with the 351 in it. Before I was buying heavy dutys because I needed to plow with them and that really seems to take it's toll. But since I decided to start using my Massey 4WD Diesel Tractor for snow removal, I decided that I didn't need a heavy duty this time out. I decided to buy an older F150 because my recent problems with the new trucks has scared me off. Besides, I couldn't stand doing any real work on these new trucks since they are so expensive and nice.
Here are some pics of the new F150 that I'm picking up. It seems to be in great condition and was a one owner:
http://www.patioponds.com/car/front.jpg
http://www.patioponds.com/car/rear.jpg
http://www.patioponds.com/car/side.jpg
http://www.patioponds.com/car/inside.jpg
http://www.patioponds.com/car/engine.jpg
Since this is supposed to be a technical comparison forum, perhaps I will compare the the technology used on the Hemi to the 3 valve, from an engineering stand point. The original Hemi concept used a domed piston underneath a semi circle shaped combustion chamber (when viewed from the side). The spark plug was put right at the apex of the combustion chamber, the ideal location. This created a flame propagation that expanded from the center out, in all directions. This avoided one of the primary problems of the wedge combustion chamber on common pass car motors such as the small block Chevy or the old 5.9L Mopar....ect. The problem with the regular wedge is that the compression expansion flow direction is opposite of the flow direction momentem of the gass'es in and out of the cylinder, particularly with the spark plug located to the out board of the head. This reduces effiency from the power, fuel consumption, and emissions prespective. It is also very vulnerable to knocking. The Hemi is much more effiecent. On a Hemi shape with the spark plug in the middle, the intake and exaust valves, can be geometrically oppossed with a straight shot into and out of the chamber. The Hemi shape has the potential for tremendous airflow at high RPM. This equals great power potential. The Hemi is much more effiecent over all than a wedge, but since the flame propagates from the center out, the flame will die out toward the outside of the chamber, because the charge becomes less dense, and the tempature is lessened. This results in high hydro carbon emissions, and that's why the original Hemi went extinct.
The new Hemi isn't really a true Hemi, but uses a pent roof combustion chamber. The Pent Roof is similar to the Hemi, in that the Spark Plug can be put in the center, and the intake and exuast valves located geometrically opposed. The Pent Roof is more emissions friendly than the true hemi, but it's still not as clean as a swirl chamber head. The pent roof isn't exclussive to Mopar, and the 32 valve Nissan Titan motor is essentially a pent roof design too. Only the overhead cam Nissan motor has 4 valves per cylinder instead of two.
Multi Valve motors traditionally have poor low end tourqe. This is because low end tourqe is a function of cubic inch volume filling of the cylinders, increasing the air charge desinity. More volume = more tourqe. This is not a direct function of cubic inch displacement by bore and stroke alone, but how much air volume you can get in there at low RPM, or volumetric effiency at low RPM. Multi Valves give as much as three times the valve area than even the biggest possable single valve, so the airflow potential at higher RPMs is tremendous, but this reduces air flow velocities into and out of the port at low RPMs. Volumetric filling of the cylinder is really helped out by high airflow velocities. Additionally, swirl, tumbling, and turbulance improve low RPM air charge density-improving tourqe.
Ford has for years used air turbulence devices in the intake tract on it's four valve overhead cam V8's. The new F150 three valve engine has Air Charge Motion Valves on the one intake port that remains in operation at low RPM. This creates good cylinder filling and high turbulance at low RPM, and hence good low RPM tourqe from a moderate cubic inch displacement. The new Ford three valve cylinder head uses swirl combustion to achieve excellant combustion effiencies.
Swirl Combustion was a Ford invention back in 1968, although it wasn't used on production Ford V8's untill 1986. Swirl combustion forces the highly turbulant flame front and the general direction of airflow to be the same, avoiding the problems of a regular wedge combustion chamber. On the new three valve, the direction of swirl, from either intake valve, is directed toward the spark plug, that is ideally located in the exact center of the combustion chamber. The exaust valve (on the opposite side of the chamber from intakes) is huge and can flow more than enough exaust gas for a redline in excess of 6500 RPM. 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, plus good low end tourqe from a smaller cubic inch displacement. It is more technologicly advanced than the Hemi, and light years ahead of GM's old fashioned push rod, 2 valve, wedge chamber, Vortec V8's.
I recently saw a hot rod magazine exclaim that the Gen III Vortecs were the most significant engines of our time. What? What a load of bull that is! They knew their readers and what their readers wanted to hear though.
Last edited by P51D Mustang; Jul 24, 2004 at 02:08 PM.
Ford Trucks for Ford Truck Enthusiasts
Now my opinion, does the hemi feel much more powerful then the 5.4? No. But it is. period. The dodge still outpulls the f150 everywhere except extreme low end, which is useless with an automatic trans.
As to the seat of the pants thing, the dodge 5.9 "felt" stronger than any 5.4 that i have ever driven(even ones in an f150, 03 and older), and I own a 5.4 f250SD. If I didn't like the 5.4 I wouldn't have bought one. The power is enough to get my 33"s to burn no problem. I do hear that the 5.4 is all low end, but I really don't see it. My midrange is far the strongest part of the powerband. I will so much as say that my old 4.9L felt stronger under 2000 RPM's, but that was in a truck that weighs some 2000 pounds less and had a manual trans. My Sd is still faster.
thank you for your oh-so informative post. Any actual info to add?
Don't mean to seem like a jerk, but this is where we come for actual info, not jaded statements w/ no facts behind them. Would you also agree that the 5.4 shouldn't be in 3/4 ton trucks? Why? Just because the hemi has a wider power band doesn't mean it doesn't have it where it counts. If you disagree, show me some proof to the contrary. I've been in both, the Hemi wins-hands down.
My neighbor 2 doors down has one w/ the 5 spd. He only tows twice a month w/ it (livestock-mostly cattle). Has always more than satisfied his needs. I've ridden in it loaded down and it did just fine.
Last edited by tdister; Jul 26, 2004 at 04:52 PM.
thank you for your oh-so informative post. Any actual info to add?
Don't mean to seem like a jerk, but this is where we come for actual info, not jaded statements w/ no facts behind them. Would you also agree that the 5.4 shouldn't be in 3/4 ton trucks? Why? Just because the hemi has a wider power band doesn't mean it doesn't have it where it counts. If you disagree, show me some proof to the contrary. I've been in both, the Hemi wins-hands down.
My neighbor 2 doors down has one w/ the 5 spd. He only tows twice a month w/ it (livestock-mostly cattle). Has always more than satisfied his needs. I've ridden in it loaded down and it did just fine.
I bought the Hemi 1500 and after being severly dissapointed and embarrassed towing my boat up the cajon pass at 45 MPH, I traded it in and got a V-10. I would completely agree that the 5.4 should not be in the 2500 and 3500, its too much weight for that engine, and what the truck was designed to do.
However, Ford at least gives an (Gasser) option to go to the V-10. Dodge just offers the Hemi.....while great in a car or that station wagon thing....is not the optimal engine for the 1500 let alone the 2500 or 3500. The engine is not desinged to tow....I know first hand. Plus Ford does not market the 5.4 as the "be all end all" engine on the market, Dodge does, and its not.
Plus I would not drive a Dodge again after seeing this
http://www.ford-trucks.com/forums/sh...44#post1801344
Last edited by SuperDutyHaulin; Jul 26, 2004 at 05:33 PM.
Edit:Sorry , your post wasn't their when I started typing (yeah I'm slow). the biggest thing that those 2 Images have in common is that I'm a big fan of each.

I guess we'll just have to disagree. It seems to me they do just fine towing-especially w/ just a boat. Hmm.
Last edited by tdister; Jul 26, 2004 at 05:56 PM.



