guess what concerns me is dyno test compared to the real world. when a engine is on the dyno the load is applied at small incerments and then hp and torque is measured. with the bigger cube engine you have more rotational mass, so when the load hits fast (like in the real world when you hit a hill with 20,000+ gross), it will keep the momentum better. the smaller cube engine with less rotational mass will be brought to it's knees alot faster. seems we all ready see this now. powerstroke, cummings, and duramax all have pretty close torque #'s right now but when you run them side by side with a load and hit a big hill what usually happens?? the big cube powerstroke just rolls on. guess i would like the idea of the 7.3 with all the new high tech built into it and then we have a real power plant.

parts man

 

You are certainly entitled to your opinion, Parts Man, but I don't necessarily agree with your analysis of how a dyno measures power. When you hit a hill with a vehicle with lots of rotational mass the kinetic energy will indeed help you up the hill until it runs out. Then it is up to the engine's ability to make power to maintain your speed. So the only thing gained by lots of rotational mass is the kinetic energy in that mass. Once that is gone, you're on your own. Once you've got your rotational mass up to speed it is no longer a factor as far as the dyno is concerned. 525 ft. lb. of torque at 1600 RPM on a dyno is fixed, regardless of the weight of your rotational mass once it is up to speed.
The point I was trying to make about the smaller engine upping the ante in this horse power race is, it is torque that actually turns the wheels. But because a large number of people buying trucks nowadays are people who are more familiar with the way the auto industry advertises and promotes horse power in that segment of the industry, it seems to me that Ford and GM have begun putting more emphasis on horse power than torque and, consequently, the consumer is getting a skewed picture of the capability of the truck as it relates to pulling a load.
Please don't misunderstand -- I am not against new technology but I have lived long enough to know the necessity of making business prove their claims. I was just as skeptical of the 7.3L Power Stroke's fuel injection system until I actually saw it in action and understood how it works. All Navistar has to do to bring me into the fold is get me an engine to run on the dyno. If it does what they say it will then I'll be their biggest promoter. Until then I'm a skeptic.

 

>I've seen the same numbers you have, Steve (I may have read
>it on your previous post). What I want to see is the engine
>running on a Dyno that has been calibrated by someone I
>trust. I am not impressed with advertised torque and horse
>power figures put out by the people trying to sell me a
>vehicle.
>Just because I'm paranoid, it doesn't mean they're not out
>to get me!


Here is the "misinformation" in a number of posts that I am responding to:

>on the 6.0L engine but it seems to me that this new engine
>is going to get its horse power by running faster. I hope
>they realize that torque is what gets the work done.

The published specs indicate GREATER torque, which as you rightly point out is what REALLY matters, at the SAME RPM range as the 7.3. Having a longer powerband is just a bonus... if I'm pulling a load, and I get another 900 RPM to play with before I have to shift, well I guess I'll wait for you at the top of the hill.

All of this discussion about rotating mass, how the torque is developed, the weight of the engine, etc... is irrelavent. The mass being propelled at the wheels could care less as long as it sees more ft-lbs coming at it than before.

Now, if you want to make the claim that you don't TRUST Ford's numbers, then well there's not much I can do to address that. I'm not a Ford apologist, but from what I've seen in the published numbers in specs for their IDI and PSD enignes, they've been relatively spot-on over the years. Cackle, of course, non- withstanding. ;-)

Finally, people seem to be equating weight and displacement with longevity and reliability. Composite materials, alloys, forged materials, turbos, intercoolers, fuel injectio, etc... injection are ALL ways of either getting the SAME strength out of lighter materials, or delivering GREATER efficiencies for a given amount of fuel.

Frankly, there IS a replacement for (some) cubic inches. It's called engineering.


-Steve

 

I'll second what Steve said. The company I work for has been putting a 7.3L inline 6 cyl. engines in class 8 trucks for nearly 30 years. Sure, it produces more torque, but not much more HP. I think most of us are still stuck in the rut that more cubes are better. It used to be that it took alot of displacement to burn all the fuel that was required to make that much power. Now, with precise injection timing and fuel rate mapping along with variable geometry turbo charging, you can make as much power in a smaller engine as you could in one 10% larger. I've seen 2000 HP from a DT466 in superstock pulling tractors.

 

I am sure you are right, Steve, and I am fairly sure Ford isn't going to hit the market with an engine that won't compete with the GM Duramax (the people I've talked to running the Duramax are very pleased with the performance). I am not trying to say that more power isn't better or that the same power over a wider RPM band isn't better. But, these words in your previous post sum it up: "published specs." What I want to see is if the "published specs" are anywhere near the reality. Let me just give you this example: As far as I know we are presently using a generic 235 horse power program in our test cells to test the Power Stroke engines on. The low limit for horse power acceptability is 178 HP. On average, most engines register about 196 HP plus or minus about 5 HP. Keep in mind these engines are not broken in yet (they will typically have anywhere from 15 to 25 hours of green growth in them at which time the power numbers will level off). As you can see the numbers are nowhere near the rating of the program and that is the basis for my skepticism. There is absolutely no doubt in my mind that the 6.0L Power Stroke will do the published spec numbers. My question is, how much will be left when the EPA and the warranty gurus are done with it?

 

>Let me just give you this
>example: As far as I know we are presently using a generic
>235 horse power program in our test cells to test the Power
>Stroke engines on. The low limit for horse power
>acceptability is 178 HP. On average, most engines register
>about 196 HP plus or minus about 5 HP. Keep in mind these
>engines are not broken in yet (they will typically have
>anywhere from 15 to 25 hours of green growth in them at
>which time the power numbers will level off). As you can see
>the numbers are nowhere near the rating of the program and
>that is the basis for my skepticism.

You're mixing your apples and your oranges.

The HP rating of 235 is for the Engine at the flywheel.

When you dyno, you are measuring rear-wheel HP. RWHP numbers are ALWAYS less that flywheel HP.

Assuming you get another ~10HP once the engine is borken in, that's a total dyno measuremnet of ~205HP. You then have approximatley 30HP of parisitic losses between the flywheel and the rear wheels. This is due to driveline friction, power-steering, alternator, radiator fan, etc... That certainly is within expected ranges.

Again, I maintain, people are criticizing what they do not understand, or have even yet to see.

-Steve

 

You are correct, Steve, in saying the 235 HP is flywheel HP. But you are not correct in saying I'm comparing apples to oranges because we measure the HP at the flywheel (I may not have been clear about that in my previous post). When we were running the 6.9/7.3L IDI engine, we used a correction factor to correct for ambient conditions (temp, humidity, barometric pressure, etc.) and we used a different correction factor program to calculate HP on the Ford engines than on the Navistar engines for the sole purpose of realizing an inflated HP figure. If you calculated HP of a Ford engine using the Navistar correction factor program it was ALWAYS lower and if you factored a Navistar engine with the Ford program it was ALWAYS higher. What I'm telling you, Steve, is 2 things: (1) they have, will and are using smoke and mirrors to convince the consumer that their numbers are correct for advertising purposes (everybody else is doing it too) and (2) I want to see this engine run on a properly calibrated dyno, right before my very eyes, and plot my own HP and torque curves. I've worked long enough for this company to know when to believe and not believe what I'm being told.

 

I'd be willing to bet that Joe's numbers are coming from an engine dyno and not a chassis dyno.

In regards to emissions, will this engine have egr or exhaust aftertreatment along with the VG turbo?

 

It is indeed an engine dyno and not a chassis dyno.

The 6.0L engine does have an EGR set-up.

 

>You are correct, Steve, in saying the 235 HP is flywheel HP.
>But you are not correct in saying I'm comparing apples to
>oranges because we measure the HP at the flywheel (I may not
>have been clear about that in my previous post). When we
>were running the 6.9/7.3L IDI engine, we used a correction
>factor to correct for ambient conditions (temp, humidity,
>barometric pressure, etc.) and we used a different
>correction factor program to calculate HP on the Ford
>engines than on the Navistar engines for the sole purpose of
>realizing an inflated HP figure. If you calculated HP of a
>Ford engine using the Navistar correction factor program it
>was ALWAYS lower and if you factored a Navistar engine with
>the Ford program it was ALWAYS higher. What I'm telling you,
>Steve, is 2 things: (1) they have, will and are using smoke
>and mirrors to convince the consumer that their numbers are
>correct for advertising purposes (everybody else is doing it
>too) and (2) I want to see this engine run on a properly
>calibrated dyno, right before my very eyes, and plot my own
>HP and torque curves. I've worked long enough for this
>company to know when to believe and not believe what I'm
>being told.

I dunno what to tell you, Joe. If you follow any of the forums regarding increasing RWHP (lots of this type of discussion at diesel-central.com), you'll find that a pretty acceptable "baseline" range for REAR-WHEEL HP numbers is in the in the high 190's (for the 235HP engines) to the 220's (for the 250HP) engines. With auto tranny's.

If you are saying that 196 is the average for the engine prior to parisitic losses, then your experience seems to be drastically different than alot of people for whom HP output is a very passionate subject.

Addtionally, a number of people working on the "cackle" problem have dyno's the 7.3's (using a chassis dyno) and have RWHP as good, or greater than, your flywheel HP. (see http://www.texastowncar.com/ for one such example). Kim Lux has spent quite a bit of time working on the cackle issue, and along the way has built a kit that will crank out 350-400 flywheel HP, and he never made mention of inadequate initial HP readings.

So, I guess this means your mileage may vary ;-). Unfortunatley you seem to have varied a lot farther south than many people.

All I'm trying to say, is let's look at REAL issues that may surface with the 6.0, rather than condemning the design ahead of time with arguments (i.e- displcement...) that really may not be sound from an engineering viewpoint.

At the same time, if you have sufficient data that you can prove to back up the problems you;ve seen with those engines, you might want to "bring it to Ford's attention". They seem to have had to address the Mustang problem recetly after a few "polit suggestions" from potential customers.

I'll cease my input in this thread now.

-Steve

 

Both Steve and Joe have valid points. Joe sees dyno readings on engines right off the assembly line. After that engine breaks in, it should increase in HP. Parasitic loss thru engine friction and driveline is typically 15-20% though more likely on the low end of the scale.

 

It is quite possible that I am wrong about our use of a 235 HP program for our testing purposes in light of the rear wheel HP figures you quoted in your previous post. We may be using a 215 HP program - I'll see if I can find out for the purpose of setting the record straight.
I certainly hope you are right, Steve and I suspect you are, judging by the feed back I'm getting from the Duramax crowd, about the HP figures for the 6.0L engine. One thing we've got going in our favor is our engineering department. They converted our old 446 MV8 into the 6.9L diesel on a shoe string, giving us a viable product to sell and make some money on. Then they did it again by engineering out all the short comings of the IDI engine when they made the Power Stroke, in addition to developing the new injection system. Now they've given us a variable pitch turbo and second generation injectors which are smaller and, as such, will undoubtedly be less expensive to manufacture for the 6.0L. I am just antsy about getting my hands on an engine for testing. They are installing a production test cell that should be ready by summer and building a new Quality Audit facility that may be ready before that. So as soon as I have some information, you-all Ford Truck Enthusiasts listers will be the first to know.

 

Anyone have a confident and informed comment about production date on the 6.0? I am ready to buy an X with 7.3 PSD, but might wait and throw the dice on the 6.0 if it is coming soon. :P

 

Ford is supposed to start building 6.0L equipped vehicles on Nov. 4, 2002.

 

i'm an old guy, so i remember old sayings.. "THERE IS NO SUBSTITUTE FOR CUBIC INCHES!!" that goes back a few years..

jim