wnjj
Cornelius, Oregon
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azwildcat99 wrote:HP = Torque * RPM/5252 So unless you are revving your engine up above 5200RPMS or racing F1 at 19k RPMS, HP is largely irrelevant. It's the torque that matters. Diesel or Gas your TV makes more torque than HP at the engine speeds we are pulling at, any of us. Given that, a diesel usually has superior figures (500+ vs 300-400).
Running below 5252 RPM only means the arbitrary units of HP are lower than the arbitrary units of ft-lbs. You can't compare those two numbers as is and it's only by coincidence that they are even similiar in an average engine. We can just as easily use kW instead of HP to describe engine output power. (1 HP = 0.745699872 kW).
Again, a torque spec is USELESS without including the RPM it can produce that at. Without the RPM component you cannot make anything move. If the RPM at which an engine produces all its torque is lower than needed to turn a driveshaft to propel a truck at 60 MPH, you need to gear it up.
Here's the thing plenty of you keep ignoring: When a powered shaft is geared up (output is faster than input), the RPM goes up but the torque goes down proportionally. The HP in equals the HP out. The same is true in reverse: When the output turns slower than the input, the torque goes up while the RPM goes down. Use the equation above to convince yourself if you don't believe me.
What this means is you generate more driveline torque (and therefore more wheel torque) when running in a lower gear than you do in a higher gear. This equalizes things at the wheel for the high-rev'ing gasser running in a lower gear than the diesel. In the end, both are running the same wheel RPM to acheive the same ground speed. The gas engine just uses more of the gearing to trade its high RPM for wheel torque. The ONLY constant is HP from crankshaft to wheel where it's needed (minus some losses due to friction.)
Sure, there is a cost in both RPM and fuel comsumption for the gasser but that does not have anything to do with whether it "can" do it.
Don't misread what I'm saying here. I'm not saying diesels aren't the better tow vehicle. I'm just trying to show that it isn't simply because they have higher torque. Their higher torque is a consequence of they way they operate at a lower RPM which translates to "working less" for most people. Most diesels also have turbochargers which keeps them making most of their HP at high elevation. They're also far more efficient at using their fuel.
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azwildcat99
Arizona
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Joined: 07/31/2012
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wnjj wrote:azwildcat99 wrote:HP = Torque * RPM/5252 So unless you are revving your engine up above 5200RPMS or racing F1 at 19k RPMS, HP is largely irrelevant. It's the torque that matters. Diesel or Gas your TV makes more torque than HP at the engine speeds we are pulling at, any of us. Given that, a diesel usually has superior figures (500+ vs 300-400).
What this means is you generate more driveline torque (and therefore more wheel torque) when running in a lower gear than you do in a higher gear. This equalizes things at the wheel for the high-rev'ing gasser running in a lower gear than the diesel. In the end, both are running the same wheel RPM to acheive the same ground speed. The gas engine just uses more of the gearing to trade its high RPM for wheel torque. The ONLY constant is HP from crankshaft to wheel where it's needed (minus some losses due to friction.).
I understand and agree with what you are saying. Your statement above was one of the main reasons why I got rid of my gas engine. That, and it was a 1500 (too small for my TT). I didn't like using those RPMS and gearing to pull grades. Plus there wasn't anything left in reserve. I was out of gears.
As for my diesel decision, I didn't see the jump to a heavier vehicle with less HP (300 vs 315), but a little more trq (335 vs 360) an upgrade. I was considering an 04-08 2500HD 6.0. However, with the diesel and only 45 more horses (360) but double the torque I climb the hills without issue and can always drop down several more gears if needed since the grades only drop me to 4th. That was the basis for my torque argument.
That was just my preference. I don't mind my cars revving, but didn't like my truck doing it. Sounded cool, but not so much while towing.
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rhagfo
Portland, OR
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So this is a great debate on the merits of GAS vs Diesel. It gets me thinking of how many of the I don't like Diesel folks have actually driven or towed with a diesel truck??
It is easy to say gas is fine and I don't want diesel cost too much too much maintenance, fuel is too expensive, etc.
Well currently a two year owner of a used 234K when bought, currently 252K Cummins, and I will not be going back to gas any time soon!
I pull a 12k 5er with a 5.9 liter straight six at or over the 55m mph speed limit through the Oregon coast range with a set of 3.55's, and it loves every minute of it.
I get 12 mpg with that load in tow, at those speeds. Even with the 5er in tow the fuel gauge hardly moves.
The post that the Gassers, that think diesel is not a good thing, should read the post from those that have finally took that step, and post Darn this pulls like a locomotive, and only sips fuel.
My 1st diesel experience was neighbor gypo logger, and my daughters Diesel VW Dasher! I learned a lot with both of those experiences.
Russ & Paula the Beagle Belle.
2016 Ram Laramie 3500 Aisin DRW 4X4 Long bed.
2005 Copper Canyon 293 FWSLS, 32' GVWR 12,360#
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64thunderbolt
Az
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Sport45 wrote:Natural Gas Poised tp Penetrate Long Haul Fleet
Diesel rules the roost in OTR trucking because it makes financial sense for vehicles that are on the road 8+ hours per day. If gasoline or natural gas becomes cheaper that's what they'll use. You can get all the power you need from any fuel. There's nothing magical about any of them.
When did you visit a gas station. Gas is already considerably cheaper than diesel. Try and get 500K miles out of a gasser towing. Isn't going to happen.
Glen
04 Tail gator XT 34' 5th wheel garage model
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64thunderbolt
Az
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Sport45 wrote:Natural Gas Poised tp Penetrate Long Haul Fleet
Diesel rules the roost in OTR trucking because it makes financial sense for vehicles that are on the road 8+ hours per day. If gasoline or natural gas becomes cheaper that's what they'll use. You can get all the power you need from any fuel. There's nothing magical about any of them.
The natural gas vehicles do no fair to well here in the desert heat. They lose a lot of power in these high temps. Maybe in the future they can remedy this. Again, how long will anything but a heavy duty diesel run before a rebuild?
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Hannibal
Tampa Bay Area
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Joined: 04/12/2002
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rhagfo wrote:So this is a great debate on the merits of GAS vs Diesel. It gets me thinking of how many of the I don't like Diesel folks have actually driven or towed with a diesel truck??
It is easy to say gas is fine and I don't want diesel cost too much too much maintenance, fuel is too expensive, etc.
Well currently a two year owner of a used 234K when bought, currently 252K Cummins, and I will not be going back to gas any time soon!
I pull a 12k 5er with a 5.9 liter straight six at or over the 55m mph speed limit through the Oregon coast range with a set of 3.55's, and it loves every minute of it.
I get 12 mpg with that load in tow, at those speeds. Even with the 5er in tow the fuel gauge hardly moves.
The post that the Gassers, that think diesel is not a good thing, should read the post from those that have finally took that step, and post Darn this pulls like a locomotive, and only sips fuel.
My 1st diesel experience was neighbor gypo logger, and my daughters Diesel VW Dasher! I learned a lot with both of those experiences.
I've owned and towed with six diesels. When I bought my first diesel, I said I'd never go back to gas. Bored my family and friends to tears with all the reasons why. I got over it. Now I'm happy to be towing with an engine that can rev again. It's all perspective.
2020 F250 STX CC SB 7.3L 10spd 3.55 4x4
2010 F250 XLT CC SB 5.4L 5spdTS 3.73
ex '95 Cummins,'98 12v Cummins,'01.5 Cummins,'03 Cummins; '05 Hemi
2017 Jayco 28RLS TT 32.5'
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Ram4Sam
Redlands, Calif
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Hannibal wrote:rhagfo wrote:So this is a great debate on the merits of GAS vs Diesel. It gets me thinking of how many of the I don't like Diesel folks have actually driven or towed with a diesel truck??
It is easy to say gas is fine and I don't want diesel cost too much too much maintenance, fuel is too expensive, etc.
Well currently a two year owner of a used 234K when bought, currently 252K Cummins, and I will not be going back to gas any time soon!
I pull a 12k 5er with a 5.9 liter straight six at or over the 55m mph speed limit through the Oregon coast range with a set of 3.55's, and it loves every minute of it.
I get 12 mpg with that load in tow, at those speeds. Even with the 5er in tow the fuel gauge hardly moves.
The post that the Gassers, that think diesel is not a good thing, should read the post from those that have finally took that step, and post Darn this pulls like a locomotive, and only sips fuel.
My 1st diesel experience was neighbor gypo logger, and my daughters Diesel VW Dasher! I learned a lot with both of those experiences.
I've owned and towed with six diesels. When I bought my first diesel, I said I'd never go back to gas. Bored my family and friends to tears with all the reasons why. I got over it. Now I'm happy to be towing with an engine that can rev again. It's all perspective.
Come on H....you know you are just foolin' yourself.....you miss the clatter.![[emoticon]](http://www.coastresorts.com/sharedcontent/cfb/images/awink.gif "awink") ![[emoticon]](http://www.coastresorts.com/sharedcontent/cfb/images/cool.gif "cool")
Sam
2016 Dodge cummins 3500 SRW LB CC 4X4 Aisin, Nav, white w/brown
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rhagfo
Portland, OR
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Ram4Sam wrote:Hannibal wrote:rhagfo wrote:So this is a great debate on the merits of GAS vs Diesel. It gets me thinking of how many of the I don't like Diesel folks have actually driven or towed with a diesel truck??
It is easy to say gas is fine and I don't want diesel cost too much too much maintenance, fuel is too expensive, etc.
Well currently a two year owner of a used 234K when bought, currently 252K Cummins, and I will not be going back to gas any time soon!
I pull a 12k 5er with a 5.9 liter straight six at or over the 55m mph speed limit through the Oregon coast range with a set of 3.55's, and it loves every minute of it.
I get 12 mpg with that load in tow, at those speeds. Even with the 5er in tow the fuel gauge hardly moves.
The post that the Gassers, that think diesel is not a good thing, should read the post from those that have finally took that step, and post Darn this pulls like a locomotive, and only sips fuel.
My 1st diesel experience was neighbor gypo logger, and my daughters Diesel VW Dasher! I learned a lot with both of those experiences.
I've owned and towed with six diesels. When I bought my first diesel, I said I'd never go back to gas. Bored my family and friends to tears with all the reasons why. I got over it. Now I'm happy to be towing with an engine that can rev again. It's all perspective.
Come on H....you know you are just foolin' yourself.....you miss the clatter.
Sam
X2
Nothing beats the Clatter of a Cummins in the morning! LOL!![[emoticon]](http://www.coastresorts.com/sharedcontent/cfb/images/grin.gif "grin")
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Hannibal
Tampa Bay Area
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Ram4Sam wrote:Hannibal wrote:rhagfo wrote:So this is a great debate on the merits of GAS vs Diesel. It gets me thinking of how many of the I don't like Diesel folks have actually driven or towed with a diesel truck??
It is easy to say gas is fine and I don't want diesel cost too much too much maintenance, fuel is too expensive, etc.
Well currently a two year owner of a used 234K when bought, currently 252K Cummins, and I will not be going back to gas any time soon!
I pull a 12k 5er with a 5.9 liter straight six at or over the 55m mph speed limit through the Oregon coast range with a set of 3.55's, and it loves every minute of it.
I get 12 mpg with that load in tow, at those speeds. Even with the 5er in tow the fuel gauge hardly moves.
The post that the Gassers, that think diesel is not a good thing, should read the post from those that have finally took that step, and post Darn this pulls like a locomotive, and only sips fuel.
My 1st diesel experience was neighbor gypo logger, and my daughters Diesel VW Dasher! I learned a lot with both of those experiences.
I've owned and towed with six diesels. When I bought my first diesel, I said I'd never go back to gas. Bored my family and friends to tears with all the reasons why. I got over it. Now I'm happy to be towing with an engine that can rev again. It's all perspective.
Come on H....you know you are just foolin' yourself.....you miss the clatter.
Sam
I miss my '01.5. I might own another some day but, the perspective has come back to reality. ![[emoticon]](http://www.coastresorts.com/sharedcontent/cfb/images/biggrin.gif "biggrin")
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Jarlaxle
New England
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64thunderbolt wrote:Sport45 wrote:Natural Gas Poised tp Penetrate Long Haul Fleet
Diesel rules the roost in OTR trucking because it makes financial sense for vehicles that are on the road 8+ hours per day. If gasoline or natural gas becomes cheaper that's what they'll use. You can get all the power you need from any fuel. There's nothing magical about any of them.
When did you visit a gas station. Gas is already considerably cheaper than diesel. Try and get 500K miles out of a gasser towing. Isn't going to happen.
Watched an F-550 repo truck wind up 553,000 hard miles on its V10...it got a Jasper engine and it still in service. The truck is 12,000lbs empty and sees lots of idling, city use, PTO use, and the occasional fast getaway.
John and Elizabeth (Liz), with Briza the size XL tabby
St. Bernard Marm, cats Vierna and Maya...RIP. ">
Current rig:
1992 International Genesis school bus conversion
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