rcpd34
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Jarlaxle wrote:Nothing. He is absolutely 100% correct.
Please explain, in detail and with links to sources, EXACTLY how 300HP from a Ford V10 spinning 4500RPM is different from a 300HP C10 Cat at 1700RPM, 300HP from a Cummins ISB at 2400RPM, or 300HP from a turbocharged Honda at 8500RPM. If each engine is moving equal weight and geared appropriately, they will perform exactly the same climbing hills. It is basic physics!
Note: been there and done that at work. We had two tractors, both with 275HP...one got 275HP with about 850lb/ft from a big Cummins (I think an ISM), one got it with maybe 600lb/ft from a Cat C7. With the same weight, they climbed hills at THE EXACT SAME SPEED. The C7 just had to spin higher, and was geared accordingly. (Power peak was 2300 versus, IIRC, 1800.)
Then why does Chevy rate the Duramax with the 3:73 with a higher towing capacity than the SAME truck with a gasser with the same rear or even a 4:10? Look at the ratings over the past 10 yrs or so and you'll see even the BB wasn't rated as high. Look at the HP rating as well you'll see the common factor in the highest rating is always Torque. And diesel = torque. By reading your statement, I can take that 300 HP Honda, put it in my pickup and tow my 11K lb trailer? I think not. There is no replacement for cubic displacement.
Brian
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Jarlaxle
New England
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Probably the transmission. The 6L90E isn't as strong as the Allison. And, of course, many people are like you and think that revving any engine over 2500RPM is not appropriate for towing...it is, of course, perfectly fine.
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rcpd34
MD
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Jarlaxle wrote:Probably the transmission. The 6L90E isn't as strong as the Allison. And, of course, many people are like you and think that revving any engine over 2500RPM is not appropriate for towing...it is, of course, perfectly fine.
The 8100 came with the Ally. Same tranny. I love the big block. Here is my sig from another forum:
2008 Chevy 2500HD 4x4 LTZ Z71 CC/SB LMM
Edge Juice/Attitude, MBRP DPF back 304 SS Exhaust, SuspensionMaxx Keys & more...
2006 Chevy 2500HD 4X4 CC/SB 8100 SOLD
2005 Chevy 2500HD 4X4 CC/SB LLY SOLD
2004 Chevy 2500HD 4X4 SC/LB 6000 SOLD
2002 Chevy 2500 4X4 Avalanche 8100 SOLD
2002 Chevy 2500 4X4 Suburban 8100 SOLD
2001 Chevy 2500HD 4X4 EC/SB 8100 SOLD
2000 Chevy Silverado 3500 Dump 4X4 SOLD
As you can see, I have owned gas the majority of my driving life. I can tell you from experience, if you're gonna tow heavy, you're better off with a diesel. End of story. We can now close the thread. ![[emoticon]](http://www.coastresorts.com/sharedcontent/cfb/images/wink.gif "wink")
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Jarlaxle
New England
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Keep rereading my last post until it sinks in.
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Hannibal
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John is right once again. A 200 lb man with a 4' long breaker bar can put 800 ft/lbs of torque on the input shaft of the transmission. But at only a few rpm if that. Four rpm would calculate to .6 hp. All that torque and very little rpm means very little hp which means very slow movement. Turn that up to 2k rpm and you're looking at 300hp with 800ft/lbs of torque. There you will be towing your 10k lb 5th wheel up the 6% grades with traffic. A 400 ft/lb engine at 4k rpm (300hp) will be running right along with you regardless of fuel type. Torque is only half the equation. Horsepower is what determines how fast you tow up the grades.
Part of a manufacturer's tow rating is based on "customer expectations". This more often than not as we read right here on the forums from rpmaphobes is that we run 65mph at 2000rpm empty so anything above that towing is screaming and struggling. Nothing could be further from the truth but that's what people falsely believe based on perception.
The other consideration is start ability on a grade. With a torque converter's 2100rpm stall speed, the 300hp at 2k rpm diesel will launch far easier than the 128hp at 2k rpm gas engine if they both have the same transmission and rear end gear ratios and tire diameter.
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Sport45
Not far enough from Houston, TX
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64thunderbolt wrote:Sport45 wrote:Neither gasoline or diesel is a magic elixir that changes the rules of physics or thermodynamics. A 300hp @ 1800 rpm diesel running at 1800 rpm will pull the same as a 300hp @ 4500 rpm gas engine running at 4500 rpm. If both are appropriately geared to turn their respective rpm's at 65 mph they will both pull the same at 65 mph.
They won't sound the same or get the same mpg doing it, but both will gin along happily in their power band.
What are you smokin??????????
Nothing. How can 300hp not equal 300hp???
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64thunderbolt
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TORQUE moves the world. Once more I invite any gasser with equal wgt to come pull with me. I could probably put a chain on your gasser & trailer and tow them both faster than the gasser could tow the trailer.
Glen
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Jarlaxle
New England
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By that logic, you should tow with a Poppin' Johnny! PLENTY of torque...but, of course, no horsepower.
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Sport45
Not far enough from Houston, TX
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And we all know our Abrams tanks can't climb a hill because gas turbines make their horespower by spinning fast...
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rcpd34
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Revving within limits isn't bad; I haven't seen anyone say so. 300HP IS 300HP in either a gasser or diesel. However, the diesel will out pull it every time. You can try and eplain your position with theory all you want, but the seat of your pants truth will win out every time. If you guys are happy with your gas engines, then that is great; it works for you. But don't come here and try to say that a factory gas motor will out tow or or even tow as well as a factory diesel in the same truck. It's BS.
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