Bill, it is ok that you are 17. We were all your age once. Believe me that in 17 more years your views will not be the same as they are today. You might even find yourself driving a diesel and liking it more than a gasser.

 

You forgot about the King Dude!

 

I happen to agree with you. Lower rpm's will mean the motor will last longer. If you continue to rev up the "higher hp" engine to make enough power to move that load, it will not last as long as the motor that is relaxed and taking it easy pulling the same load.

 

LOL on the Chevy. Yes, torque is the force that moves the truck. But let's say you park the truck on a steep incline, facing uphill. You put it in park, but don't set the parking brake, so the tranny is keeping the truck from rolling backwards down the hill. Now there is a significant amount of torque on the entire driveline, up to the transmission's park pawl. Just a little less torque than it would take to get the truck moving back up the hill. The torque is there, and it is constant, but there is zero motion. Hence no work is being done, and zero power is being produced.

That is true.

It's not a weak engine, it is a low-torque engine.

Given that the gas engine we've been talking about here (the V10) is not spinning 15,000 RPM, I think that it's not even coming close to the limitations of conventional gearing. Yes, you are going to have to spin the thing up to pretty high RPMs, but if you have the available gearing to do so (and Superduties do), it will work. If that were not true they would not put V10s in motorhomes.

I agree that a higher torque, lower RPM engine is favorable for towing, I have never argued against that, in this thread or anywhere else on this forum.

The problem here is semantics. You say "best", and I agree with you, but if you say "strongest", then we need further discussion. A higher-horsepower motor, with proper gearing, will put higher torque to the ground. As you reduce the speed from the engine, moving through the driveline, you increase the torque proportionally. Ignoring losses in the gearing (not an unreasonable thing to do), the HP will be the same everywhere in the driveline, from the crankshaft, to the driveshaft, to the axles.


I totally agree. Elsewhere in this thread I have described how my 330 HP 400 ft. lb. small block GMC will tow circles around my 250 HP 525 ft.lb. PSD. But I generally always pick the Ford. This morning I took the GMC, and on the freeway I had to turn the radio way up to hear Rush.

Except, the argument is not about which tows better, it is about which tows more.

I would rep you if I could, for the stimulating civil conversation, but I have to spread it around first. So, I'll just say "thanks".

 

Yes, and I thought he did quite well on Leno last night. I was expecting lots of boos from the audience, I was pleasantly surprised at how well he was received.

When he backed up to hit Gore a second time, it made my night.

 

Seems like he beat me to it. Again.

Who says they can't build a driveline designed to operate an engine that high? I believe 15,000 RPMs pushes the limit of modern torque converters, but who says it has to go into the transmission that fast?

Why couldn't they, say, put a 3:1 reduction gearset at the crank before it enters the torque converter. Hook the torque converter to that output shaft, and voila: a 5,000 RPM engine, as far as the transmission is concerned.

An engine like this, with a light enough flywheels so it could rev freely, would pull much like a PSD would. Think about it, 190 HP at the equivilent of 1666 RPMs...that's Diesel territory there.

Would it last long? Maybe. Are you famililar with a rotary engine? I believe those spin to around 10,000 in the RX-8, but it would not be unreasonable given the design to make one that could spin faster. Power at speed could be accomplished with a turbo.

Efficiency, however, would be another matter. Take an inefficient rotary engine, rev it to 15,000 RPMs and strap a turbo on it...would likely mean a 5 MPG machine.

BUT it would out tow any PSD ever made!

 

Anyone want to take a stab at how much a V10 (or even a 5.4) could tow if equipped with an 8 or 10 speed close ratio transmission?
There's a reason those over the road big rigs have 16 speed trannys.....

 

Never seen one with a 16; sounds like a dinosaur to me! Some very old trucks have some strange transmissions, so I bet it's very old.

Most common fleet trucks have either a 9-speed or a 10-speed transmission. These are probably the most common.

Some fleets, and many owner/operators use 13-speeds, or 18-speeds. Both are variants of a 9-speed. They include an extra gearset on the tailshaft of the transmission that allows you to split each gear. A 13-speed only can split the top 4 gears, while an 18-speed can split all 9.

With the 13-speed in my truck, my engine lives between 12-1400 RPMs...it never has to go outside that range unless I'm at an idle... You could stuff a V10 in a heavy truck and have it do very well, believe it or not. It would take some crazy gearing, as my work truck has 3.25 rears, but if you set it up so it would cruise at 60 MPH at 4,000 RPM in top gear, that engine would pull 80,000 lbs.

Keeping it cool would be tough. Even tougher would be making it last more than a few thousand miles with that kind of stress. But it could be done!

 

Yeah, they have no RPM range because they are huge diesels

Not necessarily true, especially in this conversation. Apples vs. oranges.

In this conversation, we are comparing a V10 and a PSD. Two entirely different motors.

The PSD has big rods and heavy pistons. It doesn't like high RPMs.

The V10 has much lighter pistons and rods and overhead cams which means a very light valve train. It likes high RPMs and was designed for it.

 

He doesn't come on until 10:00 pm. I am rarely driving around that late. Now if they'd swap Laura Ingraham and Mike Church, I'd be a King Dude listener!

There are probably a lot of forces that act on the drivetrain at any given time. The torque you are talking about does not just appear out of thin air, it is provided by gravity. I believe our friend Newton has a law concerning this that states that in order to move the truck, the engine would have to produce enough power to overcome the sum of all the forces that are acting on it. So lets just take this a little further....

Lets assume a heavy trailer on the truck and after exhaustive math, we determine that it will take 7,000 lb ft of axle torque to get it moving up the hill. Speed is irrelevant because the hill is short and once we get to the top, the amount of force required will significantly decrease. So we have a truck with a 6.4, 3.11 1st gear ratio and a 3.73 diff. At 650 lb ft of torque at the flywheel, this truck will produce 7,540 lb ft of axle torque and the truck and trailer start climbing the hill.

Now lets put a V10 in the truck. With the same drivetrain and 457 lb ft of torque, this truck produces 5,301 lb ft at the axle and the truck starts moving backward. So lets fix this problem by giving the V10 4.30 gears. Now it produces 6,111 lb ft, still moving it backward. If we keep giving it steeper gears, we have to go over 4.88 to get our 7,000 lb ft. Just in case you're interested, the 6.4 with 4.30 gears will produce 8,692 lb ft. in this scenario.

The V10, however, will pull harder at 70 mph than the 6.4 will due to hp differences. Sometimes torque is better and sometimes hp is better. By the way, my apologies for not repping you earlier. I should have.

Nobody says they can't. I thought I had in my prior post that it would take creative gearing to get it to work. I must have deleted that sentence. I would say that your solution is creative and it would probably work. In fact, you'd then have 600 lb ft going into the transmission. However, I wouldn't want to listen to the engine all day long.

 

Hey Bill, at 17 you've got a lot more towing experience than a lot of us on here. I commend anyone that works. You sir are a sign of hope that unfortunately I have lost, looking at the kids/young adults of today. I won't go off topic any more than I already have. I'm proud of you for what you do, you work hard.

 

 

Not at all. It will take time to type up, but I will try tonight.

 

So, let me ask again, what would happen if the V10 did have a 10 (or even a 6) speed transmission. Lets say a 5.1 first gear ratio, followed by 4.2, 3.4, 2.6, 1.1, and .7 od. (Nothing calculated, just grabbing mumbers).

 

Here's one for ya Bill. Don't know how much it weighed, but when I let it down on my pickup I thought the hitch was going to hit the ground. Good think I have that heavy psd up front!