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grape
05-14-2004, 08:07
Can anyone explain to me how at 3500 rpm an engine makes 340 hp for a peak, yet makes peak torque of 495 @ 2200 rpm??? To make 340 hp @ 3500 you get 340x5252/3500 = 510 ft lbs. So why isnt' the peak torque 510??????

gmctd
05-14-2004, 08:19
Maybe it's Boost pressures and timing - have you call Peninsular for an answer?

grape
05-14-2004, 08:30
I think I'd get hung up on.

AndyL
05-14-2004, 08:51
Do they show dyno graphs? Does HP and Torque at least cross at 5252RPM?

grape
05-14-2004, 09:52
both places show graphs.....and they don't turn them anywhere close to 5250

AndyL
05-14-2004, 11:24
Originally posted by grape:
both places show graphs.....and they don't turn them anywhere close to 5250 Yea, I guess that is a no-brainer! Must be a gasoline days coming back for a brief visit.

C.K. Piquup
05-15-2004, 03:57
I don`t know any formulas.But,I`ve never seen a dyno graff where torque doesn`t peak faster(lower rpm)than HP.Torque gets you going/HP makes you fly.

Salemone
05-15-2004, 06:08
Check formula. HP= RPM x TORQUE divided by 5252

495 ft/lbs @ 2200rpm =207 hp.

grape
05-15-2004, 15:07
And they claim that as peak torque, yet do the math it takes 510 ft lbs at 3500 to equall 340 hp, which they claim is peak hp. WELL YOU CAN'T HAVE IT BOTH WAYS, SO WE ARE BEING LIED TO. My point is that if one of those numbers is false, which one? And should we believe anything else they say?

grape
05-16-2004, 06:37
I guess if you tell people what they want to hear.....they'll buy it.

More Power
05-16-2004, 10:05
Just a thought.... How many environmental, physical, mechanical and computer variables could there be that interact during an actual engine dyno run while data is being collected? Could these data - should they always agree with a simple math formula at the exact moment the computer collects the data?

Just a thought.... If you are an engineer responsible for producing advertising numbers, how many engines would you dyno? Would the numbers you forward to marketing be the lowest of those you tested? The highest? The average? How would you do it? What would you report - what would you be comfortable advertising?

This whole issue is a lot more complicated than a simple math formula - yet still be accurate and honest.

By the way, Pen does not advertise here. They may never, though they have been invited many times. I've personally met with Matt Koning a few times. I've always felt he was one of the good guys - one of the few true 6.5 experts in the world.

MP

grape
05-16-2004, 10:14
should they always agree with a simple math formula.....YES otherwise it's figuring horsepower from something other than the torque the actual engine on the dyno is producing. There has not been a machine yet on this earth that figures horsepower without reading force in pounds first.

P.S. I'm probably about to get asked to not post on this website anymore.....guess it was about time

DmaxMaverick
05-16-2004, 10:40
That axe ain't sharp enough, yet?

Prozac....anybody???


Typo....Miscalculation....Whatever....It's not that critical!

I don't think they are intentionally trying to misrepresent a product, if in fact it is. It is not an exact science. Conditions change by the minute.

CleviteKid
05-16-2004, 11:24
I will support Grape as long as he is posting here. He is exactly correct; all dynamometers measure force at at distance, compute the torque, then should apply the stated formula to compute horsepower at the RPM at which the torque was measured. And it goes without saying that all this applies to ENGINE dynos. There are so many fudge factors with chassis dynos that they should only be used for comparisons, not absolute numbers.

Grape - as long as you stick to science, engineering, and the truth, (which you have) I hope you are around here for a long time.

Dr. Lee :cool:

JeepSJ
05-16-2004, 12:11
Grape,

I agree with you, too. Send them an e-mail or give them a call and see what they say. Kinda like when I e-mailed Aeroturbine and asked about dyno results between them and other aftermarket mufflers- after all, they do claim to outflow and outperform other mufflers. Turns out they aren't comparing themselves to any aftermarket products, they only compare themselves to stock mufflers, so they are the best flowing.

Draw your line, then plot your points.

C.K. Piquup
05-16-2004, 13:52
I dunno,just seems you`re making a mountain out of a molehill.I would only put a limited amount of stock in a dyno read-out.It`s not real world.They just produce numbers for those who need them.Why can one vehicle with same dyno`d hp as another identical vehicle be faster,even with the same driver?How can a 300hp diesel have more torque than a 300hp gasser?I,too,have had many conversations with Matt Konig and am impressed with his knowledge,integrity,and(I feel)honesty.I would not insult him,nor lower myself,by putting him in the same catagory as say the aero turbine muffler.

Bobbie Martin
05-16-2004, 16:59
Originally posted by C.K. Piquup:
Why can one vehicle with same dyno`d hp as another identical vehicle be faster,even with the same driver?How can a 300hp diesel have more torque than a 300hp gasser? Probably because the dyno guy lied! HP is only one factor, gear ratio, chassis set up, weight, aerodynamics all play a part as well. HP is basically torque X RPM, diesels usually turn slower than gas engines, so if the diesel has 300 HP @ 3000 and the gasser has 300 HP @ 6000, the diesel has to have higher peak torque. That's how Formula One engines get over 900 HP from 180 CID, they turn close to 19,000 RPM. At that RPM, the torque is only 250 pounds feet - still pretty impressive!

C.K. Piquup
05-16-2004, 17:53
I did say identicle vehicles,like IROC.All I`m saying,really,is the guys at Peninsular or any other company that does what they do knows more than we do about this matter and they don`t need to lie about their products.They have succeeded in building a more powerful and more reliable motor than GM with their fat pockets did.Thank them and stop crying.Who says the HP figure and the TQ figure are even from the same dyno run?Am I the only one annoyed with Grape`s rantings(right or wrong)?I was before I finally posted.This isn`t the only place you`ll see it.Hey Grape,nothing personal.If you have a bone to pick,why don`t you ask Peninsular,then let us know what they say.I look forward to more posts from you in the future and have enjoyed ones in the past.

EWC
05-16-2004, 18:11
This is starting to sound like the 8.1 vs Dmax debate and we know who won that .

As many will recall , MP and Tough Guy drove a Dmax and a Penninsular 300 HP 6.5 to Ohio with both being evenly matched . We know what the Dmax produces , what does that say about the 6.5 ?

I vote molehill .

And there is a machine that will give you HP without torque but you will need speed , weight and some others . Your local drag strip .

gmctd
05-16-2004, 18:18
Dr Lee - what is this magical figure 5252, and how was\is it derived?

AndyL
05-17-2004, 03:15
Originally posted by gmctd:
Dr Lee - what is this magical figure 5252, and how was\is it derived? Ok, here goes:

The term horsepower was derived by British inventor James Watt, who developed the first practical steam engine, used mostly for pumping water out of mines. Since water pumps had been powered by horses, Watt decided that the relative power output of his new engine should reflect a comparison with the number of horses it replaced.

Watt

Scottpearce
05-17-2004, 05:59
Horsepower is derived from torque. Torque is the amount of force exerted (actual pound-force), and horsepower is the amount of work that that force is able to do. They are two different things, but linked together. You can not have one without the other (talking engines here,guys!) Bottom line is if you increase your torque at a given rpm, then you have also raised the amount of work that the engine can accomplish at that rpm (Horsepower) Unless you are in a race-type situtation, Torque is what you feel on the street. It is the amount of force available to get your car or truck moving. Horsepower is the speed at which a given amount of force (torque) can be applied

gmctd
05-17-2004, 07:44
Thanks, Andy.
Numbers - I knew you'd hit me with numbers. I can't stand numbers! Anything over one digit makes my head hurt. ;)

Well - in for a penny, in for a pound....

So - to apply that numbers to an infernal combustion engine, should not the horsies have been walking in a pointed eliptic, or diamond, with a varying crank arm moment of 0 at the points, 12' at the center width, with pace varying from walk to full gallop?

Then, there's fuel injection - oats - and oxygen, and ignition -incentive , whereby at low traverses per minute we can get the horsies to push real hard as the arm increases to max (they can relax some on decreasing moment).
Get maximum torque, here, right? 415ftlbs, stock?

'Course, this would also be a two cycle engine - push\relax, push\relax.

Then, at high tpm, where power is also developed via inertia - combined mass of horsies and yokes and arm traveling at full gallop added to rotational shaft inertia, we would get them to start pushing as they approached the points (advance), with resultant less force applied to the max arm moment being compensated for by increased number of travels around the elliptic diamond per minute. More events per unit of time. 195hp, stock?

Gasoline engines have 'luxury' of scheduling the ignition\combustion event over many degrees across TDC - advance for rpm and horsepower, retard for torque.

Diesel ignition\combustion event occurs when compressive heat arrives at ~1625degF.

Inject fuel in advance of that, the fuel cools the compressive heat, combustion occurs later, but not enough heat to ignite all the fuel, flame goes out - we get white vapors out the exhaust.
No horsepower gains from advance there, right?

Inject fuel later, fuel is raised to combustive temps, combustion starts, but piston has been heading back down for some time already, temps drop below combustion, flame goes out - we get high EGT's, black smoke.
No torque gains from retard there, right?

Horsepower and torque each have a 'sweet spot' in an infernal combustion reciprocating engine.

Diesel 'window of opportunity' is limited, gasser can be manipulated as rpm increases.

Diesels, traditionally under-square - small bore, long stroke - are low-rpm torque monsters, don't function well at hi rpm. 1200cuin Cummins I-6 making 190hp\1800lbsft torque between 1200-1500 rpm..

Gassers, over-square - large bore, short stroke - make fair low end torque, but make excellent power from many combustion events per unit of time at hi rpm. 454cuin Chevy making naturally aspirated 550hp at 6800rpm, or 350cuin small-block doing the same at 7800rpm.

19,000rpm 180cuin 4-stroke Diesel?

Don't despair - 21st Century EFI 12000psi pilot-injection combustion Diesel technology has increased Cummins, Navstar, and Isuzu torque\horsepower range from 2200-2800rpm to 5000-6000rpm, with power levels at 600-800hp and 1000lbft torque, at ~45psi Boost.

Now, we got long stroke for torque, and many combustion events per unit of time for horsepower, with long stroke keeping the torque levels up.

[ 05-18-2004, 06:58 AM: Message edited by: gmctd ]

JeepSJ
05-17-2004, 10:06
I thought the formula for the circumference of a circle was pi*diameter, or pi*(2*radius)...

OK, never mind. You get a formula pounded into your head through years of public education, and sometimes you don't see the obvious variations until you write it down. Yeah, 2*pi*radius works. Now I'm just rambling...

whatnot
05-17-2004, 10:43
I emailed Marine Diesel and asked about it. Here is the reply:
-------------------------------------------------
Sorry for the confusion. I know the questions that's raised by the
Formula T = Hp * 5252 / Rpm. We are in the process of updating the
specifications for the engines as many of the other OEM's are doing as
well. Typically the lower rpm numbers become increasingly less accurate
as the dyno systems experience more difficulty reading accurately at
lower rpms when measuring the higher torque values. However, most users
are really not as concerned with the lower rpm Hp numbers as the torque
is what actually moves the boat, not the Hp. In most cases the Hp is a
concern at WOT rather than part throttle. MarineDiesel engines are rated
such that the charted Hp is represented by what you see on the chart,
however the actual torque is a little higher than what is claimed. This
yields a product that performs better in the boat when it's actually in
usage therefore almost always surpassing the customers expectations.

Regards,

moondoggie
05-17-2004, 10:58
Good Day!

More Power: You wrote,

grape
05-17-2004, 11:27
I find that the marine diesel usa 250 hp version fits my needs perfectly. Lets see, the chart says it makes just shy of 140 hp @ 1000 rpm. So lets do the math backwards 140x5252/1000 = 735 ft/lbs. of torque @ 1000 rpm.....I like that one. I'll take one of those for my truck :rolleyes:

AndyL
05-17-2004, 17:27
gmctd

wow, I am speechless!

gmctd
05-17-2004, 20:06
sorry! ;)

Cowracer
05-18-2004, 11:02
As a usless side note, when Watt figured out horsepower, he must have used a stout breed of draft horse. The average quarter horse can only muster about 2/3 a horspower for any lenght of time.

Then again, he WAS english. Maybe he was reading metric horsepower. ;)

Tim

Peter J. Bierman
05-18-2004, 14:04
I don't think I will publish any numbers from the twin turbo engine on this page.... :D

True or false data, we get all kinds off interesting formula's and explanations this way smile.gif

Peter

EWC
05-18-2004, 15:25
Hmmm , wonder if Grape will post dyno numbers from his engine when he's done .

grape
05-18-2004, 15:42
The scary part is, I could completely fabricate a dyno sheet as long as the numbers added up and it was believable, nobody would know. But in all seriousness...... it'll be on the superflow in a couple of weeks. Supposedly I have a 250 hp pump, per stanadyne, and the marine nozzles.....so we shall see.

moondoggie
05-19-2004, 04:40
Good Day!

Cowracer: Remember British electrics? It used to be said that the Brits drank warm beer because they had Lucas refrigerators.

grape: I hope you

Cowracer
05-19-2004, 07:38
Originally posted by moondoggie:
Cowracer: Remember British electrics? It used to be said that the Brits drank warm beer because they had Lucas refrigerators.

Yes! Mr. Lucas was also known as "The Prince of Darkness". Ever ride an old triumph with the AC electric in the rain?

moondoggie
05-19-2004, 08:40
Good Day!

No, although I'd REALLY like to ride an older Triumph someday. :(

You said 1) old, 2) Triumph, 3) AC electric, & 4) in the rain. I think these types of things are like having kids: trouble increases as a function, not arithetically (probably got this stated wrong). In other words, two kids is not twice the problems, but maybe 2^2, or four times the problems, three is maybe 3^2 or nine times the problems, etc. You've listed FOUR factors - I think I'd just push the thing in a ditch & walk. ;)

Blessings!

Brian Johnson, #5044

Cowracer
05-19-2004, 09:26
Its all the fun of licking a light socket, but without the bugs in you teeth.. ;)

You could get a nice 'tingle' if you touched the right metal parts. Not the best of ideas. If you ever get a chance to ride any old Brit bike, just remember, the brakes are merely advisory and only marginally impact the deceleration curve.

But there is no better way to tour than an old Triumph or BSA, really. You get to see a lot of the country while walking along the road looking for the odd whitworth thread bolt that fell off.

Tim

EWC
05-19-2004, 16:15
Look forward to reading your results .

C.K. Piquup
05-20-2004, 03:34
Triumph is what you feel when you make it home,riding the bike.I love the feel of those Limey Vert Twins.Last Saturday I helped a guy on roadside on a`77Tiger.It blew an oil-line and soaked his right leg and rear tire.His fault,only had a clamp on one side.It was second time out since resto.We twisted a wire on to get him a few miles back to my place(after wiping tire down with his T-shirt)to clamp it and top off with some Red-Line juice.Off he went,the fun of old bikes.All said and done,you can`t beat it.Now,about diesel power,the power to weight ratio of a K3500/2500 w/300 or whatever hp motor feels ideal.What`s really ideal is,the only way to do this makes the motor more durable(18:1).More would be nice,but not from this motor.

AndyL
05-20-2004, 03:42
Originally posted by grape:
The scary part is, I could completely fabricate a dyno sheet as long as the numbers added up and it was believable, nobody would know. But in all seriousness...... it'll be on the superflow in a couple of weeks. Supposedly I have a 250 hp pump, per stanadyne, and the marine nozzles.....so we shall see. When does she roll? Or, when will the truck be complete and driving down the road for testing?

rjschoolcraft
01-06-2006, 18:10
For the record, Grape is right in this post, as Dr. Lee stated. I've never looked at the Peninsular graphs and don't recall ever seeing this thread before. There's no magic invovled in torque and horsepower curves. Ask Grape to explain where the 5252 conversion factor comes from, though. If he cannot tell you in a few days, I'll explain it.

I have long doubted many claims made by Peninsular, as I doubt many claims made by Bill Heath. I try not to make a butt of myself over it, though...

As for attacking Grape for pointing this out, that's wrong. Any company who advertises anything or makes specific claims should be held accountable when they are found to be wrong. Bill Heath's horsepower and torque claims for his chips and reflashes is a good example. I've been corresponding with him about it. At first, he tried to just stonewall me. Then he said there is something wrong with my Suburban. Now he doesn't respond anymore.

As for all of Grape's attacks on me regarding the turbo stuff... Go back and read all the related posts. You'll see that he has taken things way out of context, put words in my mouth (or under my fingers) that I didn't say (or type) and has generally distorted facts to meet his agenda. But that's OK. To each his own. He simply doesn't understand airflow as well as he thinks he does. It's a little more complicated than the linear equation that relates horsepower and torque to speed.

You'll see that my contention with him centers around his claim that you "can move more air with less boost with a different wheel." Now he's saying that we were talking about power. We were not, I am not. That's just one example of the tactic of lifting things out of context that he has used.

It's all there in writing. Even my unfortunate angry outburst that I wish I hadn't done. We all have things that we wish we could redo...

I'll suggest a new forum handle for Grape...How about The Lone Ranger since he's from Texas. ;) (See his post in this thread (http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=009857#000013) for the context.)

rjschoolcraft
01-06-2006, 18:15
Originally posted by whatnot:
I emailed Marine Diesel and asked about it. Here is the reply:
-------------------------------------------------
Sorry for the confusion. I know the questions that's raised by the
Formula T = Hp * 5252 / Rpm. We are in the process of updating the
specifications for the engines as many of the other OEM's are doing as
well. Typically the lower rpm numbers become increasingly less accurate
as the dyno systems experience more difficulty reading accurately at
lower rpms when measuring the higher torque values. However, most users
are really not as concerned with the lower rpm Hp numbers as the torque
is what actually moves the boat, not the Hp. In most cases the Hp is a
concern at WOT rather than part throttle. MarineDiesel engines are rated
such that the charted Hp is represented by what you see on the chart,
however the actual torque is a little higher than what is claimed. This
yields a product that performs better in the boat when it's actually in
usage therefore almost always surpassing the customers expectations.

Regards, This is a bunch of techno babble-speak to avoid the issue. Much like what I received from Bill Heath... Marine Diesel said nothing in here that makes one whit of difference.

dieseldummy
01-06-2006, 19:57
Really necessary to dig up a post over a year old just to stir the pot?

Yes the math was wrong, I agree there. As for dragging Bill Heath into this that's uncalled for. We all know who your prefered vendor is so lets just leave it at that. I've seen Heaths stuff in action first hand and I can tell you that it works just as advertised. His injectors, reflash, and water injection all work very well IMO. I would guess he quit communicating with you because you come off like a rabid pitbull at times, always bold and never backing down. Give it a rest and lets get back to meaningful diesel talk.

Justin

rjschoolcraft
01-06-2006, 20:21
I didn't drag this up. Grape drug it up by linking to it and claiming to be only 1 of 18,000 people here over a 10 year period to notice. He also linked to it in the post that I referenced.

If you'd like, I can post all of my messages to Mr. Heath. You won't find any "rabid pit-bull" approaches...thank you, though, for your flattery. I cannot, in good concience, post what he wrote to me, as he asked me to keep it in confidence.

I mentioned Heath as I believed it was directly related to the topic of claims vs. reality. His chip (I know first hand) provides performance much better than stock, but does not deliver the claimed 65 hp and 150 lb-ft. That is fact. It seems that others should know about that, just as others needed to know about what Grape revealed regarding Peninsular's power and torque claims.

DD, it's also clear that at about any opportunity, you come after me. That's OK, too. I will simply refer you back to what has been written, because it stands on its own merit. I guess it's OK in your opinion for Grape to say slanderous things about me, but it's wrong for me to speak factually.

I didn't drag up the post, so your first attack was baseless. I did not, and do not, act like a "rabid pit-bull" so your second attack was also baseless.

I forgive you for them and will think nothing of them.

rjschoolcraft
01-06-2006, 20:31
For dieseldummy:

Here is the text of my comments to Mr. Heath. As I stated previously, I will not post his responses as he asked me to keep them confidential.

My initial query.

Dear sir:

Thank you in advance for your attention to this matter. I am writing to ask for dynamometer data to substantiate your claim of 65 hp and 150 lb-ft gain from your Max-E-Torq chip for the 95 6.5 Turbo Diesel. I have been running a Kennedy TD-Max chip and would like to see some data for comparison.

Ronald J. Schoolcraft
Schoolcraft Power Train
Engineering Services
2040 Country Club Rd.
Martinsville, IN 46151
(765) 346-2990
(765) 349-8458 (fax)
ron@schoolcraftpowertrain.com
www.schoolcraftpowertrain.com (http://www.schoolcraftpowertrain.com)


My reply to his initial response. His response had technical irregularities in it regarding torque converters that I corrected with this message.

Thank you for the information.

I had actually requested the data, if it is available to support the claims. If you have engine dynamometer data, that would be fine. Chassis dynamometer data would fine as well.

I am fully aware of the issues that you speak of. In fact, I am a power train engineer and have done considerable transmission design work (including torque converter design). In fact, in the speed range that you mention, there should be a multiplication effect of torque through the converter.

I have tested my Suburban (the data is available here: http://www.schoolcraftpowertrain.com/index_files/Page414.htm). This data was generated using third gear (direct) with the converter locked with a BD TorqLoc converter control. Last winter, one of your chips was provided to me at no charge for evaluation (I still have it). I have not been back to the dynamometer yet (I just finished building an 18:1 engine with splayed mains and fully blueprinted block and crank assembly). However, last winter I ran your chip back to back versus my Kennedy chip. Towing my utility trailer with a load of water (a picture of the rig may be seen here: http://www.schoolcraftpowertrain.com/index_files/Page527.htm.), I observed reduced power output and higher egt readings with your chip running the same load on the same route vs. the Kennedy chip.

It was only recently that I noticed your power claims. That is one reason why I asked the question. That's also why I asked for data, so that I may compare to what I have personally generated with my truck.

Thanks again. Hope to hear from you soon.

Ronald J. Schoolcraft
Schoolcraft Power Train
Engineering Services
2040 Country Club Rd.
Martinsville, IN 46151
(765) 346-2990
(765) 349-8458 (fax)
ron@schoolcraftpowertrain.com
www.schoolcraftpowertrain.com (http://www.schoolcraftpowertrain.com)


My second reply after he requested more information ("particulars") about my Suburban.

Mr. Heath,

You can read about all the particulars in these articles on The Diesel Page: Part I, Part II and Part III. I have a 5521 pump that was installed in October of 2000 under warranty.

The numbers on the PCM are as follows: SERV. NO. 16212488. 86BPACM251743662.

The factory EPROM is identified as BPAC 1621 6876.

The Heath EPROM has BXPW marked on the label. I'm reluctant to send it back because I would like to do more testing with it. My Suburban was down from early January through mid July 2005.

Ronald J. Schoolcraft
Schoolcraft Power Train
Engineering Services
2040 Country Club Rd.
Martinsville, IN 46151
(765) 346-2990
(765) 349-8458 (fax)
ron@schoolcraftpowertrain.com
www.schoolcraftpowertrain.com (http://www.schoolcraftpowertrain.com)


As you can see, no "rabid pit-bull" attack here. Hope this helps. smile.gif

Edited to fix problems with the quoted links.

[ 01-06-2006, 10:00 PM: Message edited by: ronniejoe ]

dieseldummy
01-06-2006, 21:40
RJ, I hadn't seen the post Grape made. I made a hasty post, for that I truely apologize.

What you just posted is nicer than what I could have ever imagined considering the way you can argue here. It may seem that I take any opportunity to pick on you, but that is not the case usually. I admit that I have taken unfair jabs at you and this may have been one of those times.

I feel that there should be some level of clartiy on certain things and it just happens that you seem to be on the other side of things lately. You seem very good at posting one part of a senario and are equaly good at discrediting the other parts of it that you don't agree with.

Back to the Heath part of the story... I still don't see how he relates to Pennisular and Marine diesel's math irregularities. If you truely feel that he misadvertises his product maybe you should start a new thread dedicated to his deception as you see it. I would love to add my .02 to the story.

I mean no disrespect to you in all of this. You are obviously an accomplished engineer and you are most likely smarter than most of us that post here. Just try coming down to our level for once since I highly doubt I'll be making it up to yours. ;)

rjschoolcraft
01-06-2006, 22:50
Originally posted by dieseldummy:
RJ, I hadn't seen the post Grape made. I made a hasty post, for that I truely apologize. No problem. We all do things that we wish we hadn't. As I already said, I forgive you. As far as I'm concerned it's over.


Originally posted by dieseldummy:
Back to the Heath part of the story... I still don't see how he relates to Pennisular and Marine diesel's math irregularities. If you truely feel that he misadvertises his product maybe you should start a new thread dedicated to his deception as you see it. I would love to add my .02 to the story. I saw it related in this way: A claim has been made that I have solid evidence is inaccurate. I've made mention of it here before and have been soundly criticized. Grape caught flack for pointing out the Peninsular claim. The two situations are parallel.

I hope everyone notices that I defended The Lone Ranger here. I really hold nothing against him and find his recent belligerence entertaining. I am truly glad that I've found a new friend as he says in his signature and profile.


Originally posted by dieseldummy:
I mean no disrespect to you in all of this. You are obviously an accomplished engineer and you are most likely smarter than most of us that post here. Just try coming down to our level for once since I highly doubt I'll be making it up to yours. ;) Justin, I'm just a farmboy who was fortunate enough to be blessed with mechanical ability and the opportunity to study engineering. My hands are stained with grease and mud from years of hard work. Two weeks ago, I put my three sons and my dad to work with me cutting and splitting firewood for two and a half days. We brought in close to a cord which will be good for close to a month. I live at your "level" and don't consider myself above anyone.

More Power
01-07-2006, 13:00
Hmm....

First let me say I've haven't gone back to read all of the posts in this thread...

I would like to point out that a marine application water-cooled intercooler (aftercooler/charge-air cooler) is a lot more efficient than those we use on our trucks.

Back several years ago I put our 6.5 Project truck on BD's chassis dyno (with more than a little tredidation) to see what it produced - during a public event - no less....

It produced 205 horsepower on their dyno - even though they ran the engine all wrong. I asked that they run the engine to 3600-rpm, because that's where the power peak would be. Instead, they ran it to 2800-rpm (that's where the ran all the Dodges), and loaded down the engine to a point of EGT problems. The TT intercooler is not in the engine's fan airflow path, and was entirely inadequate on a dyno.

Still, the Peninsular 300 hp spec 6.5 was able to produce 205 at 2800 rpm. I was frustrated by the way the BD crew ran the engine - maybe their dyno wasn't capable of running to those wheel speeds (at 3600 rpm)... I dunno....

In the end, I feel it would have produced RWHP power at least equal to the advertised 300 hp Duramax (which is in 235-255 RWHP range) if the 6.5 had been run to 3600 rpm. And, I feel the 300 hp Pen spec 6.5 engine ran well enough to satisfy their advertised power claims - in a pickup truck.

If I were building another performance 6.5, I would install an intercooler similar to the one used in Lil Red - purely for better dyno results, as well as one of Pen's hi-flow turbochargers. I have no doubt that such an engine would deliver 250 RWHP.

By the way, I feel the Spearco intercooler is fine for highway use.

Jim

More Power
01-07-2006, 14:42
Grape said: "Can anyone explain to me how at 3500 rpm an engine makes 340 hp for a peak, yet makes peak torque of 495 @ 2200 rpm??? To make 340 hp @ 3500 you get 340x5252/3500 = 510 ft lbs. So why isnt' the peak torque 510??????" OK, I went back and re-read the entire thread (not to say I didn't miss something... :D )

Here's the deal on why hp & tq might not always compute.

#1 reason is turbocharger boost pressure. Assuming you've got the fuel, most turbo diesels see an increase in boost pressure at lower rpms (say in the 1500-2200 range), which combine to increase torque.

This feature is called "torque backup". A diesel engine that produces an increase in torque as engine rpms fall (due to increasing load) is what torque backup is all about. Eventually, there'll be enough torque to stop/slow the speed loss when towing up hill.

If you compare an engine's torque curve to its boost pressure curve, you'll see a striking similarity.

#2 reason: the fuel curves for most fuel injection pumps have a fat region, with a fuel-rate that slowly decreases as rpms increase.

The above reasons are why we see different hp/tq curves than what a pure math equation might indicate. Turbo boost pressure curves and fuel-rate curves....

Jim

grape
01-07-2006, 15:24
Has anybody here actually used an engine dyno personally, I mean actually been the one controlling the water to the water wheel with one hand and the throttle in the other. I'm pretty sure what the answer to that is, so I'm wasting my time.........I'm disappointed in you MP. DYNO'S MEASURE TORQUE FIRST, THEN COMPUTE HP, that's why i smell something. Pick 1 rpm point on the graph, do the trusty ole' hp formula, and you'll see, their dyno is measuring something else.....LOL.

grape
01-07-2006, 15:36
Originally posted by ronniejoe:

I hope everyone notices that I defended The Lone Ranger here. I really hold nothing against him and find his recent belligerence entertaining. I am truly glad that I've found a new friend as he says in his signature and profile.

what is this world coming too? LOL

JoeyD
01-07-2006, 15:50
Questions with questions.
What would it matter if anyone operated a dyno before? I have had my truck on one and was operating it and the guy running it just hit the button to bring the load on. No rocket science there. Are you talking about something different?

rjschoolcraft
01-07-2006, 15:59
Jim,

I have to say here that this has nothing to do with fuel and boost or anything like that. I've gone and looked at the curves and tabular data on the Peninsular site. It can be seen here (http://www.peninsulardiesel.com/400tai/400tai.htm). On this page, Peninsular advertises an engine that makes 340 hp at 3500 rpm with a peak torque of 495 lb-ft at 2200 rpm.

Let's just focus on the advertised horsepower number. Let's not even talk about an engine to remove other confusing factors. Let's just consider a shaft that is transfering power from one device to another. For 340 hp to be transmitted through that shaft while it turns at 3500 rpm, the shaft has to be twisted by 510.2 lb-ft of torque. There is nothing else to consider.

Now, with that said, if Peninsular's engine really makes 340 hp at 3500 rpm, the torque produced by the engine at that speed must be 510.2 lb-ft. It cannot possibly be any other value.

This is where the problem comes in with the advertised data. Peninsular also advertises the same engine to have a peak torque of 495 lb-ft at 2200 rpm. This is less than the 510 lb-ft of torque that corresponds with a true 340 hp at 3500 rpm. See the dilemma?

Few Diesel engines will produce peak torque at the same engine speed that they produce peak power, unless the fuel delivery is specially calibrated to do so. However, this would produce an engine that has very poor driveability charactristics and does not accelerate a load very well from a standing start (or accelerate a boat from a stop in the water). In short, it would be completely silly to do something like this.

Typically, diesels (in the size range that we're talking about) make their peak torque between 1600 and 2200 rpm with maximum fuel flow. If the fuel flow is held steady from this point up the engine speed curve, the torque output will drop off as speed increases. This is because the pumping losses, gas flow losses, mechanical losses, etc. all increase with speed and require a higher percentage of the engine's thermodynamic power capacity to overcome them. Power will continue to increase as the torque decreases (to a point) because speed is an important factor in determining power.

It is possible, and sometimes practical, to make an engine with a very flat torque curve. This is done by limiting fuel flow at lower speeds. This will produce an artificially low peak torque number that can be held constant as engine speed increases by increasing fuel flow as speed increases. By doing this, one can hold "peak torque" (more accurately "maximum torque") from 1800 rpm all the way to 3500 rpm (for example).

This can also be accomplished over a narrower range with constant fuel flow by increasing boost pressure (to increase air flow) as speed increases.

If Peninsular's engine really makes 340 hp at 3500 rpm, then the advertised "peak" or "maximum" torque is incorrect. It must be at least 510.2 lb-ft. If the advertised peak torque of 495 lb-ft at 2200 rpm is correct, then the advertised value of 340 hp at 3500 rpm is incorrect. These two data points cannot possibly coexist. This is confirmed by the shapes of the curves on the plot. The torque curve is not flat. It also clearly peaks after 2200 rpm, although the plot is very fuzzy.

Consequently, this raises serious doubt about the data that is presented.

Edited to fix a silly spelling error. :mad:

[ 01-08-2006, 01:22 PM: Message edited by: ronniejoe ]

rjschoolcraft
01-07-2006, 16:07
Originally posted by grape:
Has anybody here actually used an engine dyno personally, I mean actually been the one controlling the water to the water wheel with one hand and the throttle in the other. Do gas turbine helicopter engines count? Although, we used mostly eddy current dynamometers so I've never had my hand on a water valve, I guess.

grape
01-07-2006, 16:17
Originally posted by Joey D:
Questions with questions.
What would it matter if anyone operated a dyno before? I have had my truck on one and was operating it and the guy running it just hit the button to bring the load on. No rocket science there. Are you talking about something different? You proved my point, you haven't, so move along. Chassis dyno's have never come up in anything I've spoken about. My question had to do with MP's torque backup senario you load the engine till it stabilizes rpm at full throttle, but RJ got the point across. I'm sure you hit the little red button and started the sampling process on a dyno jet inertia dyno.........touching, really.

rjschoolcraft
01-07-2006, 16:25
Originally posted by grape:
...but RJ got the point across. What? Are you sure you meant to say that? :D

LanduytG
01-07-2006, 16:32
You guys must be bored and have nothing to do, to dig up a thread this old. In the end does it really matter?

Greg

rjschoolcraft
01-07-2006, 16:38
Yes, it matters. The truth always matters.

LanduytG
01-07-2006, 16:56
I would suggest that Matt Koning be asked to come and explain then. Seems to me that MP is very happy with his as many others that have them. I have never heard any negitive things about their motors. Unlike some others that are around.

Greg

JoeyD
01-07-2006, 18:31
Originally posted by grape:
</font><blockquote>quote:</font><hr />Originally posted by Joey D:
Questions with questions.
What would it matter if anyone operated a dyno before? I have had my truck on one and was operating it and the guy running it just hit the button to bring the load on. No rocket science there. Are you talking about something different? You proved my point, you haven't, so move along. Chassis dyno's have never come up in anything I've spoken about. My question had to do with MP's torque backup senario you load the engine till it stabilizes rpm at full throttle, but RJ got the point across. I'm sure you hit the little red button and started the sampling process on a dyno jet inertia dyno.........touching, really. </font>[/QUOTE]The old respond to a question with a question without answering anything. You asked if anyone operated a engine dyno, I was asking you why. As if why did you want to know if anyone operated a engine dyno?

dieseldummy
01-07-2006, 18:31
I don't think that it's their motors that anyone has a problem with, it's thier false claims. Simple math proves what Grape and RJ are saying... It's all an equation just as stated above.

Dvldog 8793
01-07-2006, 18:49
Howdy
Hate to interupt things here but I just wanted to say that if all the personal and smart A** BS is eliminated from this post there really is some great information here for those of us that are not quite as high up on the evolutionary ladder. :D
Thanks for the info...in a round about way...I think....
L8r
COnley

More Power
01-09-2006, 09:40
We've all been invited to Michigan for this year's TDP Rendezvous. Peninsular would like us to include them as part of this year's activities. ----They have an engine dyno------ That would be a really good time for grape & RJ to explain HP & tq to all of us... :D

Jim

Cowracer
01-09-2006, 10:39
Michigan!?!? Sweet. As long as it not up nort dere in the U.P. I should be good for it.

Details?

Tim

rjschoolcraft
01-09-2006, 11:18
Here's the raw data from my max run in June of 2004:

EngSpd : WhlTrq : WhlPwr
RPM : lbs-ft : Hp
1778 : 411.0 : 139.1
1794 : 391.0 : 133.6
1810 : 378.9 : 130.6
1827 : 371.5 : 129.2
1843 : 368.4 : 129.3
1859 : 369.2 : 130.7
1876 : 373.7 : 133.4
1892 : 381.1 : 137.3
1908 : 390.5 : 141.9
1924 : 401.5 : 147.1
1941 : 411.0 : 151.9
1957 : 420.8 : 156.8
1973 : 426.9 : 160.4
1990 : 432.3 : 163.8
2006 : 434.6 : 166.0
2022 : 434.6 : 167.3
2039 : 433.1 : 168.1
2055 : 431.1 : 168.7
2071 : 429.1 : 169.2
2088 : 427.7 : 170.0
2104 : 426.5 : 170.8
2120 : 425.9 : 171.9
2137 : 425.4 : 173.1
2153 : 426.0 : 174.6
2169 : 426.5 : 176.1
2185 : 427.2 : 177.8
2202 : 427.5 : 179.2
2218 : 428.1 : 180.8
2234 : 428.3 : 182.2
2251 : 429.1 : 183.9
2267 : 429.6 : 185.4
2283 : 430.0 : 187.0
2300 : 430.7 : 188.6
2316 : 431.1 : 190.1
2332 : 431.6 : 191.6
2349 : 431.7 : 193.0
2365 : 431.7 : 194.4
2381 : 431.2 : 195.5
2397 : 430.4 : 196.5
2414 : 430.1 : 197.7
2430 : 429.5 : 198.7
2446 : 428.9 : 199.8
2463 : 428.3 : 200.8
2479 : 428.0 : 202.0
2495 : 427.7 : 203.2
2512 : 428.2 : 204.8
2528 : 427.9 : 206.0
2544 : 427.4 : 207.0
2561 : 427.2 : 208.3
2577 : 427.0 : 209.5
2593 : 426.4 : 210.5
2609 : 425.4 : 211.4
2626 : 424.7 : 212.3
2642 : 423.8 : 213.2
2658 : 422.5 : 213.8
2675 : 421.9 : 214.8
2691 : 421.4 : 215.9
2707 : 420.6 : 216.8
2724 : 419.6 : 217.6
2740 : 418.5 : 218.4
2756 : 417.5 : 219.1
2773 : 415.5 : 219.4
2789 : 413.6 : 219.6
2805 : 411.6 : 219.8
2821 : 409.6 : 220.1
2838 : 407.5 : 220.2
2854 : 405.9 : 220.6
2870 : 404.2 : 220.9
2887 : 402.5 : 221.2
2903 : 400.6 : 221.4
2919 : 398.8 : 221.7
2936 : 397.1 : 222.0
2952 : 395.4 : 222.2
2968 : 393.4 : 222.3
2985 : 391.8 : 222.6
3001 : 390.1 : 222.9
3017 : 388.5 : 223.2
3034 : 386.9 : 223.5
3050 : 385.3 : 223.8
3066 : 383.4 : 223.8
3082 : 381.9 : 224.1
3099 : 380.1 : 224.2
3115 : 378.3 : 224.3
3131 : 376.4 : 224.4
3148 : 374.8 : 224.6
3164 : 373.2 : 224.8
3180 : 371.3 : 224.8
3197 : 369.5 : 224.9
3213 : 367.3 : 224.7
3229 : 365.1 : 224.5
3246 : 362.8 : 224.2
3262 : 360.4 : 223.8
3278 : 358.3 : 223.7
3294 : 355.9 : 223.3
3311 : 353.8 : 223.0
3327 : 352.0 : 223.0
3343 : 349.9 : 222.7
3360 : 347.8 : 222.5
3376 : 346.1 : 222.5
3392 : 344.8 : 222.7
3409 : 343.8 : 223.1
3425 : 342.8 : 223.6

If we use N to represent speed in RPM, Q to represent torque in lb-ft and P to represent power in HP, Each set of three values (reading horizontally) will fit this equation: P = (Q * N) / 5252. Calculate each point and see. As an example, I'll do the last line. The torque at that point is 342.8 lb-ft and the speed is 3425 RPM. (342.8 * 3425) / 5252 = 223.6 HP (rounded to the nearest tenth).

This data in plotted form looks like this:

http://www.schoolcraftpowertrain.com/Pictures_&_Data/MaxPowerData.jpg

From this data, we see that my engine made max power of 224.9 HP at 3197 RPM. At that point, it was making 369.5 lb-ft of torque. We also see that it made its max torque of 434.6 lb-ft at 2022 RPM. At that point it was making 167.3 HP. Therefore, peak torque and peak power occur at different engine speed points, but at each of those points the relation P = (Q * N) / 5252 is satisfied.

Also notice that the torque curve is essentially flat from 2000 rpm to 2650 rpm. Above 2650 rpm, the turbocharger is limiting the mass throughput of air.

Please note, I have not accused Peninsular of lying or dishonesty as others have. I am simply pointing out that there is a problem with the data that calls into question the test results and validity of the claims. Peninsular is most likely honest and sincere in their presentation, but the data is honestly and sincerely problematic.

The graph on the Peninsular web site is illegible so it's hard to figure out where the error is. The torque at 2200 rpm may well be 495 lb-ft, but it is not the "peak" or "max" torque. If the 340 HP at 3500 RPM is true, then "peak" torque is 510 lb-ft and we simply have a problem with definition of terms.

Now it's really up to Peninsular to address the issue. I've tried to explain this without being inflammatory and really believe that I've done a pretty good job of it. It's up to you all to decide whether you accept or reject the explanation. Maybe Dr. Lee will chime in again. Maybe you'll all take his word. I certainly hope to be able to attend the Rendezvous at their facility.

jspringator
01-09-2006, 14:15
What dates this summer?

More Power
01-09-2006, 15:34
We're in the early stages of planning. Actually, I've only known about it since Friday. In addition to seeing their power engines, we'll also be showing their fuel economy engines and related parts. Hopefully, we can get some engine dyno time to demonstrate what effect building for power and for fuel economy really mean.

I need to attend a couple of diesel events this summer as well as the 2006 Pull-Off here in Montana. We'll work the Mich Rendezvous into the mix. I'll probably be flying in... smile.gif

I'll supply the slide rules and pocket protectors for grape & RJ's hp/tq seminar... :D

Jim

Tough Guy
01-09-2006, 16:32
Big Ron-

Was that dyno info from your *old* engine?

Either way those are good numbers...

Chris

rjschoolcraft
01-09-2006, 16:51
Originally posted by Tough Guy:
Big Ron-

Was that dyno info from your *old* engine?

Either way those are good numbers...

Chris Yes, that was data taken on 6/19/2004 at Kennedy's open house.

Thanks!

Marty Lau
01-10-2006, 08:32
Originally posted by Cowracer:
As a usless side note, when Watt figured out horsepower, he must have used a stout breed of draft horse. The average quarter horse can only muster about 2/3 a horspower for any lenght of time.

Then again, he WAS english. Maybe he was reading metric horsepower. ;)

Tim Then you got Electric motor Horse power which is as I understand is a true HP number and then you internal combustion Horse Power which is something less than electric Horse power. For example a water pump recomends 2 hp electric motor or 5 hp gas motor. Seems to be a whole bunch of Horse manure to me in the HP measuring game to me. A HP sould be a HP. :confused:

Cowracer
01-10-2006, 09:02
Originally posted by 16ga SxS:
Then you got Electric motor Horse power which is as I understand is a true HP number and then you internal combustion Horse Power which is something less than electric Horse power. For example a water pump recomends 2 hp electric motor or 5 hp gas motor. Seems to be a whole bunch of Horse manure to me in the HP measuring game to me. A HP sould be a HP. :confused: 10 hp is 10 hp. is all the same. The problem is that internal combusiton engines have very little torque at low rpm. If the gas motor slows down due to load, it can run right out of its torque curve and stall.

An electric motor will actually make more torque as it slows down from syncronous speed. Also a 2 hp electric will be more than happy to make 5 hp until its windings melt down.

Thats why you need a bigger HP IC motor

Tim