First solar powered circumnavigation

1, what year vette's are you talking about? IRS sucks for drag racing. I wouldn't consider any vette less that a full chassis car a drag racer. They suck in the 1/8th or 1/4. They are top end freeway flyers. I would pick any other car over a vette for a drag strip. Huge wheel, tires with no sidewall=crap off the line. I've built sbc, bbc, lsx, bbf, sbf and have been through the Mopar range fairly thoroughly too. Diesels, ive been through hundreds. I've been low 5's in the 1/4, in a car I built. Chassis, suspension, engine, trans, rear end, you name it. From a rusty roller to a consistent 5.1 bracket car. 813bbc style engine and 44lbs from the whipple. With these cars, you build more rpm to kill some low end torque, otherwise they won't hook up. Ever heard of "torque management"? There is a reason they don't call it hp management. I don't understand your hp/liter comment, as I haven't stated engine sizes, or a specific engine.

2, I was reffering to the hp wars with the big 3. Identical vehicles would get a cam change and claim 20 extra hp every year. But, if you read the peak hp and peak torque rpm, you would see that they made the hp by revving the engine higher. They also usually lost torque. I know with Chevy trucks, my 93 towed better than my 98. Same gears, trans everything. It just had the mid range to pull whereas the 98 you had to rev it to tow halfway decent. The 93 was down 60hp and 20ft lbs, but did everything better. But rpm=wear. Hp does not, unless it requires higher rpm.

3, Explain please. The 6.2 diesel in the hummer is one of the lowest rated diesels on the market. If military, almost all were non turbo. Even the civilian turbo version was pathetic. When you add the 10,000 lb truck you aren't doing very good. Plus, it has an enormous amount of parasitic losses through the drivetrain. You know there is a gear reduction box at every wheel right? Plus the oddball lockers in the diffs suck power too. Most of those trucks don't see 150ft lbs at the wheels. There was a guy racing Baja in one that had been swapped to a built duramax. He did pretty good last time I checked.

I don't watch much drag racing. It's the cheapest form of racing around here, so I've done it plenty, but I ain't watching someone else doing it unless I built something they are running. I spent 5 years as a motorcycle road racing instructor, taught msf courses, and even did a little 4 wheeled instruction too. Let alone racing too. I'll let you in on another little secret, my all time personal favorite car for either road racing or drag, is a vw bug. Gotta love the torque of a big bore long stroke vw with a turbo on it. Once you have driven one, you will wonder why anyone would want a v engine. Another FYI, between rock crawling, desert racing, dune buggies, road course, jet ski's, and all the other stuff I've built and raced over the years, I would put drag racing in as 10% or less overall. Sure, it's cheap easy and fun, but I'm not watching people make passes unless they are paying me.

Also, your 300z to vette reference could get me going on a whole different, kinda related tangent. Engine layout has a lot to do with power delivery. In line, v, opposed, rotary, even radial, they all have ups and downs, but inlines and opposed are my favorites. Why, torque.

You don't lose deck space, see here: http://www.charterworld.com/news/wp-content/uploads/2012/01/Solar-powered-boat-PlanetSolar.jpg

HP is power (kilowatts multiplied by a constant) -> energy per second. It's the most fundamental and important "number" for an engine.

For a given power you can gear the engine down: reduce rpm and increase torque; or gear it up: increase rpm and reduce torque.

Yes, if it has enough power it does.
But its torque = power/rpm, so the lower the power, the lower the possible torque.

A constant means just that: a number that is constant and doesn't change.
I don't know the constant for imperial units off the top of my head, but in metric units we use kW = constant * kNm(torque) * rad/sec(revolution speed) (where constant = 1)

See above. High torque is fairly useless at very low rpm. You need high power to have both decent torque and rpm. (100 kNm of torque is pointless if you are only at 10 rpm!)

The tractor on a farm, or the big rigs you see driving on the road, have far more toque than any car you've ever driven, but that alone isn't enough to make them competitive in a race.

Without enough power you have to lower your rpm too much to gain the torque you need.

Or to put it in terms that might be more palatable to you: a 600hp engine will produce more torque at a given rpm (say 1000 rpm for argument's sake) than a 500hp engine will at the same 1000 rpm.

Or, to put it another way: which gear in your car gives you the highest torque?
First gear. You won't win any races in it though.

1, Incorrect. It is no way the "fundemental" measurement of an engine. It is being heavily overvalued in ads, but anyone with an IQ understands marketing hype.

2, I'm sorry but that was an idiotic statement. I compared a 6hp lister diesel to a 6hp Honda or Briggs. The lister is massive, but only rated at 6hp. More than 100ft lbs, and at 600 rpm. The little wanna be lawnmowers also make 6hp, but have no torque. I've seen 6hp listers running 20k generator heads with no problems. 6hp at 3600 rpm won't do it.

3, it is supposed to be a constant for the bore/stroke combo, not every engine. Using the recognized "constant" was how the big 3 overinflated their hp numbers years ago. And it spread and I have to explaine the truth yet again.

4, High torque at low rpm is harder to harness in some applications, but is easy and more efficient in others. Power generation for one. How many of the islands still make power from those old low speed diesels? Still in service because they last forever and sip fuel. Lost of them still in use in the oilfield too. Although I will agree, 10 rpm is a little low to harness for most uses.

5, I grew up on a farm, and have a class A cdl. Sure, that 100hp tractor doesn't move fast, it's geared to pull. Behind a 100hp tractor, I've had a 20k lb implement ripping a 30ft swath through hard dirt. Try that in a miata. But there is a guy putting old tractor engines in old ford trucks, his personal truck with a 45hp runs over 100 and gets over 40mpg. As for semi trucks, have you ever seen a truck rodeo? Ever seen a guy pull his haul truck into the barn, pull the sleeper and slap 4 slicks on the back? Then turn 10,s in the 1/4? I have. I've seen an oilfield daycab Pete with a 600hp cat get some slicks then turn 12's in the quarter. Some company's speed limit their trucks, but the only thing that really slows them down is 80,000 lbs. Try running a similar hp, high rpm engine in the place of that cat/cummins/Detroit, ain't gonna happen.

6, Incorrect again. Sort of anyways. Torque is power, hp is bs. If you have the torque, and the correct gearing, it will get you moving just fine. Hp is only an indication of the upper limits of your powerband. To get a real idea of an engines output, you need both peak hp and tq numbers, plus the rpm's they occur at. Hp is part of the equation, but useless without the corresponding info.

Quoting the power isn't a complete picture, but it takes into account both torque and rpm. Quoting torque alone completely ignores rpm (and torque is useless without sufficient rpm).

No, for 100 lb ft (not ft lb, btw - that's work, not torque) at 600 rpm you need about 11.4 hp. Don't forget you need to measure the torque and rpm at the same point: you can't measure the rpm at the engine, but the torque after a gearbox.

I'm not sure what you mean by "20k" but if you mean 20 kW, that's also wrong. 6 hp is only about 4.4 kW.

No, it's simply physics. The imperial units are the mess that they are, and require constants (i.e. numbers that don't change) to be consistent. The constants are defined by the units, not by any entity, and they've existed for as long as the units have.

Like I said, for metric units no constant is needed.

I don't see a point being made here...

Absolutely correct: a 100 hp tractor is geared low - so it has high torque (pulling ability) but low rpm (speed).

A miata doesn't need that extreme pulling power, but it does need more speed.

You're only repeating back to me what I've told you. With the same hp, you can have either high rpm or high torque (raising one lowers the other for a constant power). Both are important, but to different degrees for different applications: a tractor needs torque but not much speed, a miata needs speed but not much torque.
To increase one without sacrificing the other you need more power (hp).

Torque is NOT power! You lack a fundamental understanding of what's being discussed.
Could another engineer (or some laymen) jump in here and confirm what I'm saying please. Perhaps being the loudest side of the argument will be more useful than being correct

You need to know any two of power, torque and rpm to have the full picture. Once you have two you also have the third.
Torque and rpm "come from" power, not the other way around.

I think I should repeat this: at 1000 rpm a 600hp engine will produce more torque than an otherwise similar 500hp engine will at the same 1000 rpm.

1, I will disagree with you here. Hp tq and rpm of both are needed for the whole picture. In the automotive world, I would prefer to see the average of both between their peaks. And the rpm between peaks. Or even tq and hp at peak tq, and both at peak hp. This gives you an idea of how linear the power comes in and falls off. Far more important than some random hp number.

2, sorry about the confusion, autocorrect on my phone does not seem to allow a capital w behind a k. I even went back and edited them, but it changed back before posting. But yes, an English engine rated at 6hp at 600rpm ran a twenty thousand watt generator head. I've seen a 12/2 lister running a 25 thousand watt head, and running, via belt, an antique sawmill. Both at the same time, no issues. You can go by made up numbers all you want, I'll go by what I've seen with my eyes.

3, I'll agree that imperial measurements are a mess, if I could help you and use metric, I would, but then I would be lost. But you are wrong. The constant is based on the bore and stroke, because of physics. That's how it was written in all the old engine building books I have. Most are older than me. Why has this gone away? Because a lot of auto makers would have to do some backtracking.

4, You said power at too low rpm is useless, I stated that it depends on application. Yes, I would think your 10 rpm suggestion was too low, but I've never seen an engine designed to operate that low.

I'm not repeating anything back to you. That that truck will blow the doors off a stock miata with half the hp. Weighs 2, 3 times as much too. Does it with less than half the rpm. Why? Because it has good torque where it's needed. Same truck hauls over 10k lbs of hay regularly. Gets better mileage too. Auto manufacturers build disposable, inefficient trash so their products will have to be replaced. And they have succeeded very well with their marketing to the ignorant. Also, you called semi trucks slow, I said only if they are loaded. Run an empty one and you will see otherwise. Know what gears to skip to keep one in the torque, and you can surprise a lot of wanna be hot rods. Maybe downunder the lorries and such can't get out of their own way, but around here you don't want to get in front of one unless you are gonna throw the hammer down.

6, Do you know the definition of horsepower? The horse, rope, weight and what not? Isn't that just a measurement of the ft lbs the animal could move? A bs, made up number from the start.

Engineer huh? That explains a lot. You have been taught the bs they want you to know. Conditioned to over examine the unimportant, and ignore what matters. My step father is an engineer, I know all about y'all.

Incorrect. If I tell you 400hp at 6000rpm what does that tell you? What if peak torque is 400 at 5500rpm. Or if peak torque is 400 at 3000 rpm. That is the diff between a peaky, hard to drive engine, and a nice torquey driver.

Hi,

Torque is a moment of force about a point.

If as you say you have seen a 6hp engine driving a 20 kW Alternator do you know if a true 20 ekW was being pushed out of it or was it only able to produce the same electrical power less a few losses for friction, power factor etc as the mechanical power being used to drive it?

There is no such thing as free power, there have been a number of claimants to this amazing fact here over the years. Most have had to go back to the Snake Oil sales dept after being unable to show with a modicum of sound facts that their methods were really able to defy gravity and replace themselves at the same time as they are producing the energy to defy gravity and replace themselves.

The long and short of it - If you are producing 6 hp or 4.4 kW at the flywheel you will not be turning that into 20 ekW.

Any two of the values gives you the third at any point.
power = torque*rpm
torque = power/rpm
rpm = power/torque

6hp is 4.4kW, 4.4kW is 6hp. They are the same thing by a different name.
You are saying "an English engine rated at 4.4kW at 600rpm ran a 20kW generator head."
Either "ran a head" means something other than "ran it at its maximum rated power", or you've discovered a free source of energy that will solve the world's energy problems and make you the richest man in history....

You're talking about some other number. The "5454" constant is unit conversion. EDIT: here's a derivation of it, demonstrating where it comes from: http://www.epi-eng.com/piston_engine_technology/power_and_torque.htm#equation

My point was that you can't care only about torque. Rpm also matters, and when you increase one you decrease the other unless you also increase power.

Torque is useless without sufficient rpm (whatever that happens to be for the given application), and rpm is useless without sufficient torque.

I said that an engine geared for maximum torque at the expense of rpm isn't suitable for racing. Trucks were a bad example - they need speed as much as cars do. The gearing in a truck trades torque for rpm as the gears get higher, and a truck engine generates a lot of power, so they can seem impressive when compared to a smaller, less powerful engine.

No, it isnt. ft-lb is a measure of energy. lb-ft is a measure of torque. hp is a measure of power.

"They"?
Engineering isn't a cult.

Torque at 6000rpm is 350 lb-ft.
To increase torque to 500 lb-ft at the same rpm I'd need a power increase to 571hp.

Power at 5500rpm is 419 hp.
To increase torque to 500 lb-ft at the same rpm I'd need a power increase to 524hp.

Power at 3000rpm is 228 hp.
To increase torque to 500 lb-ft at the same rpm I'd need a power increase to 286hp.

I'm not here to discuss what is more pleasant to drive. I posted in this thread because you said power is irrelevant, made up, only exists for marketing purposes, and that only torque matters - none of which is true. Power is absolutely fundamental to everything we do.

How about we race each other in cars? I'll drive a miata, and you can drive a car with a hypothetical engine that has as much torque as you choose to name, but then I get to choose its power output: you'll lose every time.

K1w1, I don't know what the total power output was. It was from a blog about how the guy kept his place powered during a hurricane. Powered his whole house, ran pumps in the basement and he ran extension cords to those around him to help out. 11 days, 7 gallons, and powered everything without issue. Out government outlawed importing these engines as "gross polluter" although almost nothing will match them. I have seen in person a 12hp version running a house, wood shop, and it also turned a sawmill via belt. People being taught fake bs about hp keeps the lies alive.

Chapstick, you need to spend some time on a running a dyno. After that you would see exactly how false your made up numbers are. I can pull the same hp at the same rpm out of a inline 4 and a v8, and there will be a massive torque difference. Over 2500 engines tuned on a dyno, and I had to learn to ignore the bs that you think is law. I've had 2 engines with identical parts throw down vastly different hp and torque numbers. I have dozens of times retuned a car down from highest hp because this helped torque considerably and made the car faster. One case, dropping 65ish hp brought the torque up through the powerband and made the car faster. Just fuel and timing adjustments. Maybe in engineer land that doesnt happen, but in real life it does. Here is another, my 06 cummins is rated at 325hp 610tq, my 93 is rated at 140hp 400tq. The 93 gets better mileage, pulls better and is quicker. Slightly Modded my 93 dyno'ed 275hp 930tq but the 06 with similar mods runs 510hp 840tq. The old trucks makes it by 3200, the 06 peaks at 4000. The 93 blows the doors off the 06. These are real dyno numbers, not dynojet bs. I bet your fake math says that's wrong too.

Oh yea, I almost consider engineers a cult. People so out of touch with reality it's crazy. If the math don't work, it can't happen. Even if I have seen it happen a thousand times. There are exceptions to that rule, but for the most part it's true. My best friend is an engineer, but he works in the oilfield fixing all the screw ups made by the behind the desk engineers. When their 6 months of r&d fail miserably, he gets paid half a mil a day to make it work. Me and him have been building engines for years, and he will straight up tell you that everything he learned in school was bs in real life.

You should dig that machine out and re produce it if it is that good.

Different strokes for different folks I guess. I hold a Merchant Navy Chiefs ticket, I was a time served and qualified diesel mechanic before going to sea. I remember quite a lot of what I learned in school as it has proved to be sound and valid engineering practice for many years. Maybe our schools were better than your friends one.

The guy still runs it as backup power. Lister engines do it all the time. They are just hard to find for sale. People who live off the grid love them. The Indian clones aren't easy to get into the US anymore. I do have somewhat of a collection of different old mid and low speed diesels. I originally mentioned my s10 with an electric motor and a diesel generator. Burns less than half a gallon an hour and will cruise on the freeway no problem. I got called a liar. Sold it a couple years ago, but it worked great. There were vids on YouTube, nothing I posted, not much on putting pics of my stuff online. Ended up racing a Prius on video, and people recorded it at little car shows.

Maybe you have that backwards. I posted my friends base rate, and he is booked solid.

Every once in while, you read something that you have to respond to...even though you know it's pointless.

I am a member of the engineering "cult"; in fact you could say that I'm among the worst of the "cult-ies" (M.S.E.E. and M.S.C.S.). I have, in the course of my career, helped develop (automotive gas) engine control modules and transmission control modules. I have calibrated both, and have designed automated transient fuel calibration systems for several US auto OEMs. So I have a little experience with these topics...

Your Cummins 5.9 was designed by a bunch of engineers. The "hard parts" (mechanicals), the fuel system...all of it was designed by engineers. I know this because Cummins is one of my customers; I talk to someone at Columbus (you know, where the engineers...well, engineer) almost every day. We sell them software, developed by a bunch of engineers, that Cummins engineers integrate into their engine controller. Engineers also engineered the pickups your beloved 5.9s sit in, and designed the dynometers that your truck(s) (with your 5.9s) posted such impressive numbers.

More bad news: civil engineers designed the road(s) on which you drive your fleet of 5.9-eguipped Dodge Rams. And, even worse, engineers (thousands of guys so nerdy that they make me seem normal) designed the very PC that you used to (somewhat crudely) express yourself...along with all of the silly Internet stuff that makes this site possible.

"Horsepower" is a measure of rate at which work is done, and is no more "made up" than any other unit of measurement. I have heard the "made up" statement before, and it is a fallacious assertion that is based on the fact that it is a "complex" measurement, meaning it is calculated and not directly measured. Horsepower is no more "made up" than weight, which itself is product of mass and local gravitational acceleration and thus is not an absolute measurement.

And finally...if you think for a millisecond that those of us in the industry are some suppressing 100 mpg carburetors and such...I would be happy to show you the billions that the industry spends trying to realize incremental (sometimes less than 1%) improvements. I know managers that would sell their souls (despite the fact that they're engineers) to figure out a way to use some blogger's mystery engine to defy physics.

I'm not kidding - you find your way to Detroit and I'll be happy to introduce you to several of the people that design your toys, and give you a chance to run your ideas by them. Just be advised - they're engineers...

Mike

Engineers are needed. I understand that. But outside of your own circles, most of your kind have a reputation for over analyzing little things. Please don't take offense to the cult comment, I was reusing what an engineer gave me. Maybe there are better terms, but y'all are a group with similar views and ideals, at least as far as your training goes.

But, you bring up my favorite automotive diesel, the Cummins. Can I blame you for the fact that they have lost their legendary reliability? How about that mess known as the cp3? Once the new batch of engineers got their hands on the old 6bt, she took a beating. Fuel mileage nowhere near what it used to be, lighter weaker internals, higher hp, but long gone is the idle to redline powerband they once had. The old engineers had it right, the newbies with the "hp is king" mentality have done nothing but destroy a once incredible engine. Engineers did ok on the LSx line for gm, so I guess y'all aren't all evil.

Hi,

The old ones were mostly great iron, the 555 on the other hand was an absolute POS and cost some transport operators all they had and they would have been designed by the same engineers who designed the good ones.

I know the a, b and c series pretty well, fairly limited on their v engines. Personally I think an inline is the best layout for a diesel because of the power delivery and torque. I know some of their older stuff, but it's all been inline. From what I've seen, the v's have always been a shortcoming for Cummins. I do know, in otr trucks, the vast majority are inline. The v8's only being popular where the truck ends up in mud, construction and oilfield mainly. But you can over rev (trucker term for revving past the power) the v's if you are in the mud, rather than shifting and losing momentum and getting stuck. But they use more fuel, don't last as long, and don't haul as well.

Just because an engineer did right once, doesn't mean they will always get it right.

I intended to stay far away from this discussion and certainly will stay away from the technical aspects. It's strayed so far off topic it's amazing anyway. But your characterization of Engineers is really over the top in my humble opinion. I've worked with and met some incredible engineers in many fields. I respect their training and respect more those who also have experience. I am not going to ever characterize any group of people by a few I've met who I may not have liked as well or felt were not competent. After all, I'm not going to characterize all Texans just based on your posts here.

Arguing the facts is one thing but when it includes personal attacks and calling others "idiots" it's too much. And, when it condemns at entire profession, then it's just too much for me to ignore.

Olderboater, I know well that there are are exceptions to that rule. I rank all engineers together in a lot of annoying habits that they all seem to have. I am in no way stating that they are stupid or useless. I do posses quite a bit of respect for them. I in no way mean to insult their intelligence. My comment about the idiotic comment was true though. He mentioned hp, but not rpm or torque. Without those, the comment had no context, thus was useless blather thrown in to baselessly support his claim.

Rereading my posts, maybe I sound angrier than I intend. Please, if my comments seem cross, write it off to me wanting to kill my phone. Between autocorrect and tiny buttons, there is about to be an iPhone shaped hole in my wall.

Yes, you do sound very angry. Glad to know it's just at your iphone. Still the use of idiot in a debate is more like a street fight. And again all engineers don't have the same habits. Maybe you seem to bring those habits out more in them? Actually that could well be with your prejudice against them, that it immediately becomes somewhat confrontational so you both come at it from your backgrounds which are very different.

Maybe I tend to hang out with a less politically correct crowd as well. Folks 'round here like to pick at each other. Lol. I know quite a few engineers, consider most of them friends, my best friend and my step dad are engineers. And every one of them shares quite a few little things, reliances on theories that in themselves could use some updating. That's not a bad thing really, it helps them be quick and efficient at what they do. I just believe some stuff is relied on too much and slows or deters a lot of innovation.

Well, my history has been that marketability deters more innovation than anything. We only built safer cars because they were mandated. Otherwise someone making a car safer was going to be at a disadvantage due to price. Same with most of our environmental moves. In terms of consumer products, I've often faced a better product being developed but with the problem of figuring out if there was a way to sell the public on it being better and to get them to pay for it. If it's more product than they are demanding it just isn't likely to succeed. There is virtually nothing any of us have that can't be made better. The question is would we pay for better and how would we know.