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Old 06-26-2007, 08:06 PM   #29
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Dyno
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Old 06-27-2007, 02:37 PM   #30
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If they can get the same power out of two less cylinders it sounds like a winner to me. I have a 450 with the V10 and after two and a half years I have no complaints. I do however plan on keeping this rig for many years (12 or so) and wonder if over the long run the V10 will hold up better? Drive what ya like I always say be happy. Scotty.
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Old 06-27-2007, 08:25 PM   #31
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<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WinnebagoDRVR:
Dyno </div></BLOCKQUOTE>

Something is wrong.

Seems to me there are lots of errors and one should not rely on these numbers.

HP is (rpm x torque) divided by 5252. The Dyno measures the torque and HP is derived from that with this formula. SO, at a given RPM a higher torque means a higher HP. Not the case for your figures. How come?

Was the entire test done in top gear? It sure looks like it (at least to an engineer I'm on the phone with who I've asked to look at your numbers because they just don't seem right).

The V10 gets its peak torque of 420@3250 rpm so your numbers make even less sense (unless you pulled a few plug leads to even the playing field ) as you have it still rising after that point. HP at 3250 should be about 260 and you are showing less than 225. Peak HP is 305@4250. But, the numbers do look ok for the Chev that has peak HP of 300 at 4400 rpm and peak torque at 4000 rpm.

IF (and I really question it) your torque numbers are correct, your table should look like this:

Chev Ford
RPM Torque HP Torque HP
1000 98 19 104 20
1500 177 51 187 53
2000 231 88 229 87
2500 272 129 265 126
3000 304 174 301 172
3500 328 219 338 225
4000 345 263 366 279
4500 343 294 341 292

If I were in buying mode now I sure wouldn't want to rely on any of the numbers.

How about outlining how the Dyno testing was done, gear selections at each RPM etc.

What make of Dyno? I assume the rear wheels sat on rollers?

Now I'm really curious.

Don

ps. When I hit "post now" no doubt all the nice formatting will be destroyed.
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Old 06-27-2007, 08:54 PM   #32
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I don't know much about how dynos work. They were rollers and they also tested from the driveshaft.

I look at it this way. It was the same equipment on the two motorhomes by the same guy.

For all I care the numbers could be set from 1-10.

It's a direct comparison that shows the Ford isn't a real stomper, but I am sure the 5 speed gearbox helps it in daily driving.
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Old 06-28-2007, 07:34 PM   #33
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<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WinnebagoDRVR:
I don't know much about how dynos work. They were rollers and they also tested from the driveshaft.

I look at it this way. It was the same equipment on the two motorhomes by the same guy.

For all I care the numbers could be set from 1-10.

It's a direct comparison that shows the Ford isn't a real stomper, but I am sure the 5 speed gearbox helps it in daily driving. </div></BLOCKQUOTE>

Well, that is an understatement. If you don't understand how bad (distorted and just plain wrong including spreadsheet formula errors) your numbers were, then you really don't understand as you say. I see the folks are RV.net didn't buy much of it either.

A water brake Dyno is the cheapest and also the most difficult to get consistency with. If you search the net you will find a fair amount on this subject.

In summary, if I were a reviewer for a journal I'd just toss your paper in the round basket under my desk.
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Old 06-28-2007, 07:50 PM   #34
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Well, I've put both to the test that no one else ever has, and my butt dyno says the Ford has very little on the Chevy.

Everyone whom I've talked too which has driven both (so far 7 people) says the same.

I emailed these numbers to Banks and they responded that the numbers were 'slightly' low but 'not far off target'. That would mean that the Chevy numbers too were low but not too far off target.

That sir means in the end it is a 1-1 comparison from which to draw a conclusion of overall power and torque development between the two motors.

Feel free to go spend $200 of your own money to do the same if it makes you feel better. Or enjoy your glossy brochure and be happy.

It's so nice to be appreciated - NOT - for trying to investigate something as best I could to satify my OWN curiosity.

Should have kept it all to myself but gee, I thought I'd share my findings.

That's all.
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Old 06-28-2007, 07:55 PM   #35
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<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">It's so nice to be appreciated - NOT - for trying to investigate something as best I could to satify my OWN curiosity. </div></BLOCKQUOTE>
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">It's so nice to be appreciated - NOT - for trying to investigate something as best I could to satify my OWN curiosity. </div></BLOCKQUOTE>

Don't sweat it. I appreciate your work even if others don't.

I don't know or care much about numbers, my butt-dyno and running with my best friend and his E450 show that the Chevy holds it's own: And oh so comfortably.
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Old 06-29-2007, 11:54 AM   #36
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DRVR-I appreciate your efforts on your study. After owning 2 Ford V10's I switched to a FourWinds 28A with the 6.0 Chev V8 and I agree with you completely. I also believe the Chev wins hand down. I for one would not go back to the Ford chassis. Road Dog
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Old 07-02-2007, 10:13 PM   #37
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The question is what is truth above and what is fiction. Clearly, the numbers posted from his spreadsheet are garbage - and that I've already demonstrated.

Second, the numbers he provided for this 6.0 Chev make me wonder why I have an 8.1L Vortec. Why you might ask? Well, look at the graphs that Banks provides for the stock Chev 8.1L engine for HP and torque and you will notice that they are WAY below the numbers provided above for the stock 6.0L. Kind of reminds me of the stories of the butcher who has his thumb on the scale when he weighs our order.
Banks graphs for 8.1L Chev

Maybe the Chev measurements were made at the engine and the Ford at the rear wheels? Sure looks that way.
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Old 07-07-2007, 05:06 PM   #38
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<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by The Shadow:
The question is what is truth above and what is fiction. Clearly, the numbers posted from his spreadsheet are garbage - and that I've already demonstrated.

Second, the numbers he provided for this 6.0 Chev make me wonder why I have an 8.1L Vortec. Why you might ask? Well, look at the graphs that Banks provides for the stock Chev 8.1L engine for HP and torque and you will notice that they are WAY below the numbers provided above for the stock 6.0L. Kind of reminds me of the stories of the butcher who has his thumb on the scale when he weighs our order.
Banks graphs for 8.1L Chev

Maybe the Chev measurements were made at the engine and the Ford at the rear wheels? Sure looks that way. </div></BLOCKQUOTE>

Whether their way of testing was crap or not, the method was the same on both - And therefore a 1-1 reference on that day is a given. If you can't see that then no one can help you.

Divide all the numbers in half if that makes you feel happy. It simply doesn't matter. Perhaps they did a modification, perhaps it is crank HP. I don't exactly know.

Looks like the Ford V10 stomps your 8.1 as well then.
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Old 07-07-2007, 08:11 PM   #39
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What it tells me is that you know little about this topic and the place that did the so called dyno testing probably knows about as much as you do. (have you even taken the time to look at the revised number I posted that show your errors - or do you not understand what you did wrong?)

Last weekend I was at a race track near Detroit that was loaded with engineers from the big 3 (well, what used to be the big 3) and I mentioned your results. They all had a good laugh.

Since my 8.1 only gets 8 mpg when not towing (haven't towed our Tahoe yet but given its power maybe the Tahoe should tow the Kodiak), I've ordered one of your hot 6L replacements for it. No doubt I'll get much better mileage as well as power.

What you should do since you are so keen and no doubt really want an answer to the question is take them out on a drag strip, take weights so you can equalize the test weights, and then see what happens when the Christmas tree lights up. You might get a shock.

By the way, my first MH had a 6.8 so I've had a fair amount of experience with it. Only shortcoming we found was a 4 speed transmission (gee, just what your 6L Chev was fitted with as well and what my Tahoe has - unfortunatley [would have got the 6 speed AWD Yukon but you can't tow it 4 down).

BTW, you might wish to do a bit of googling on water brake dynos as you might find some comments about some of their shortcomings since this method is the cheapest and least accurate way to get such torque and thus derive HP (provided, of course that you use the correct formula in your spread sheet - rpm x torque divided by 5252).
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Old 07-07-2007, 09:36 PM   #40
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This article will give you some idea of the problems with dyno testing. When I found it I had to chuckle as last weekend one of the engineers did make the comment watching the butcher when he weighs the meat.
----------------------------

Truth in Testing
Dynamometers and flow benches are great diagnostic and testing tools. In essence, they are scales for measuring performance. Just be sure there's not a thumb on the scale.
By C.J. Baker
The term "dyno tested" is used a lot these days, and most people tend to accept dyno results as absolute truth. Unfortunately, dyno results are no better than the testing method used to get the results. In other words, unscrupulous operators can make the results come out to be almost anything they want. It all comes down to the testing method and the ethics of those doing the testing. Let's look at a quick example. A vehicle can be placed on a chassis dyno and accelerated to speed. Let's say this speed is 60 MPH. At this point the vehicle's engine could be switched off and a dyno reading taken. It would show a power reading even though the engine is no longer running! Why? The inertia of the rollers and the spinning tires would provide a reading.
The above example might seem far-fetched, but in truth the inertia effect of any dyno, be it a chassis dyno or an engine dyno can contribute to a flash reading that is higher than what the test vehicle or test engine could sustain under an extended steady-state load. This is a very common method of "cheating" a dyno test. Of course, the results of such a test are meaningless, but the operator can say, "The dyno showed a reading of such-and-such."
At Gale Banks Engineering, we're sticklers for testing using proper scientific testing methods. That means testing under controlled and monitored conditions, elimination of outside variables, and sustainable results. Dedication to such testing begins with the test equipment. All Banks test fixtures have the capacity for sustained load operation. All test equipment is calibrated before testing begins, and every test is fully instrumented with the results correlated to standard conditions. It's the only way to compare apples to apples – to get honest results to reveal if real progress is being made.
We have seen some dyno facilities that simply don't replicate real world conditions. For example, an engine dyno cell may lack adequate climate control. In such cases, the cell gains temperature during testing, this in turn changes the intake air temperature. Worse still are dynos that don't have adequate engine cooling water, and more importantly, adequate dyno water-cooling facilities. A water-brake engine dyno converts engine power into heat in the absorbing unit. If the water to the absorbing unit becomes progressively warmer, the water will not absorb as much heat as if it was cool. Hence, the dyno readings would change. At Banks, the dyno cells have high capacity environmental facilities and massive water tanks and heat exchangers for engine and dyno operation at a constant temperature. Similar heat problems occur on chassis dyno's if the rollers and the vehicle tires get hot. It is essential to cool both with an adequate supply of cool air. It is also necessary to move air thru the vehicle's radiator, and intercooler if so equipped, at a rate consistent with the roller speed to simulate actual road conditions. All of these things are done on Banks' chassis dyno. Assuring consistent testing conditions is the responsibility of the dyno operator. It can also be a manipulation factor for an unethical dyno tester.
As important as temperature is to the test facility, it is even more important to the engine or vehicle being tested. Simply checking oil temperature and water temperature isn't nearly enough. An engine needs to heat soak to the same level before each test. For example, if an engine is initially warmed up and then tested, and then allowed to sit for ten minutes before the next test, the block may have gained 30ΒΊ F. due to heat soak. That change in temperature will change the internal dimensions and clearances of the engine. The second test cannot then be compared to the first test. The same thing applies to the tires and rollers on a chassis dyno.
The same rigorous standards are applied to flowbench testing. The equipment is checked, temperature and relative humidity measured, and components are flowed under as realistic conditions as possible. What does that mean? Let's consider flow testing a muffler. For realistic results, the muffler must be flowed with the appropriate exhaust pipe and tailpipe in place. Any comparison to other mufflers must be done with similar inlet and outlet pipes in place. Doing such tests any other way would be to "fudge" the results.
In conclusion, testing of any kind, be it on a dyno, a flowbench, or even a road test, the results are only as good as the testing method, and more importantly, the ethics of the tester. False or inflated claims, however, have a way a coming around to bite the ones who foster them on their unsuspecting customers. In the end, if the products don't live up to claims that are made for them, the word gets around. At Banks, we're proud of our reputation. We test more than anybody else in the industry to be sure our products are the best. That's the way it's always been. That's the way it will always be.

(Editors note: In spite of all the money Banks has spent on dyno facilities, I doubt if they have the ability to "climate control" their dyno cells. I think Baker means to say the requirement to move an adequate volume of air through a cell so as to cool all the components to a reasonable value is the objective.)
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Old 07-08-2007, 07:36 AM   #41
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Same explanation but with some photos. Did your tester have good size cooling tanks? How long was the water allowed to cool before the next test? What was the order of the six test (3 for each)?
Banks on dyno testing
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Old 07-17-2007, 02:24 PM   #42
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Okay here we go now:

2006 Winnebago Minnie Winnie 26 - 13,187 pounds - E450 Chassis:

1 25.92
2 26.65
3 26.85

0-60 @time 26.47 seconds

2007 Winnbago Outlook 29 - 13,362 pounds Chevy 3500 Chassis:

1 26.96
2 27.72
3 27.55

0-60 time @27.41 seconds

Same driver, same day, same lonely stretch of road, same direction, same winds etc. etc. etc.

About a second slower to 60, but a little heavier too.

I've got a pretty accurate butt dyno.
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