RPMs While Driving

[Ace Holliday]

.........Also feel like this entire thread is a trolling attempt and was hesitant to reply.........

I agree and felt the same way.

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[dmeyer302]

I don't have a dog in this fight, but I took some unscientific measurements on the way back from lunch using my OBD scanner. "Calculated Load Value" PID.

Idling, in gear, A/C on 40% load
Idling, in gear, A/C off 30% load
General driving, accelerating 50-60% load
General driving, cruising 20-40% load
Downshifts happen around 80% load

What does it mean? No idea. Somebody else with a wheezy NA V6 needs to get some numbers to compare.

 

[Devil6]

Yes! But, you need to remember engines and engine controls were a lot different then. They have come a long way since then. These "pretty small" engines are putting out more power and torque than even V8s put out then. Remember when your car use to run on when you turned the key off? Well maybe you can't. Cars usually didn't go more 80,000 to 100,000 mile without a complete engine rebuild, if that long. As I said before if our truck sense they are in a situation that would cause lugging they will downshift. Smarter than some drivers.

Now before I violate my own rules of civility, I'm going to back out of this thread.

Yes, I certainly do remember when my GM gas pushrod engine would turn into a diesel.

I simply do t have the faith in corporations that you do.

Remember laissez faire?

 

[Devil6]

I agree and felt the same way.

These are the responses of people who have nothing of value to add but are compelled to do it anyway.

 

[Devil6]

I don't have a dog in this fight, but I took some unscientific measurements on the way back from lunch using my OBD scanner. "Calculated Load Value" PID.

Idling, in gear, A/C on 40% load
Idling, in gear, A/C off 30% load
General driving, accelerating 50-60% load
General driving, cruising 20-40% load
Downshifts happen around 80% load

What does it mean? No idea. Somebody else with a wheezy NA V6 needs to get some numbers to compare.

So, 40% load at idle. Ideal is ~800 RPM. Redline is 6500+ RPM.

Are you measuring Amps?

 

[Devil6]

I keep it at 70 mph. that puts my RPM in my bone stock truck around 1800-1900 rpm.

This is giving me an average of about 24 mpg manually calculated.

At 70 in our Civic with the CVT its crazy...I can watch it on a safe patch of road and see the actual CVT working the RPM. it will range from 2100-2400 never hanging steady in one spot.

I agree but I can’t drive 70.

 

[Devil6]

"In my opinion, this wouldn’t bother me except that at 1,500 RPM I don’t think the engine is making either 100 foot pound Of torque or horse power. "

because the engine doesn't need that extra torque and HP when you are "using enough throttle to maintain speed " at 60mph.

I think that is overlooking the the phenomenon of lugging buying too low RPM, too little power but adding too much gas causing excessive force on engine internal components.

 

[Devil6]

Were your previous vehicles all high-revving Japanese cars, by any chance? No torque at all until 4000 RPMs, because that's how they were designed?

No, trucks. My current car is a Boss 302.

 

[Devil6]

Not to mention this tranny was co-developed with GM. That's 2 sets of engineers at least on the transmission side. I would venture to guess that the Ram with an 8 speed and GMs with the 9 speed are similarly low in RPMs at the same speed.

I don't think you're going to find a smoking gun here. More gears = more opportunity to fit the vehicles current need, be it power or efficiency. The engine isn't 'lugging', it's being as efficient as possible given the throttle input and current need.

Also feel like this entire thread is a trolling attempt and was hesitant to reply...

Your ignoring that engineers aren’t the only ones with their hands in the process. There is budget people, manufacturing people, accountants, environmental, and federal.

this is far more complicated than just engineers.

 

[doug910]

No, trucks. My current car is a Boss 302.

Again, if you hate American companies so much, why do you keep buying American?

 

[Devil6]

If this engine were a Subaru FB 25 flat 4, which below 1900 rpm it makes barely enough torque to turn its own crankshaft, I'd be worried; however, if you take a look at first, the design of the 2.3 (long stroke=high torque), second at the tuning/turbo boost and gate settings, you will quickly realize just by looking at the steepness of the torque curve, that it indeed has plenty of torque at 1500 rpm to handle its own weight and the truck, especially at 60 mph...one little twitch on the skinny pedal and it downshifts to peak torque (310 lb/ft @ 3000 rpm). In comparison to my old Ranger with the 3.0 vulcan with a 5-speed manual and 3.73 gears, this combination truck engine/tranny has GOBS of low end torque; take a look at this shaft HP/torque curves someone plotted to compare a Chevy Colorado to a 2019 Ranger:

The solid green line is the Ranger Ecoboost....The 3.0 vulcan in my old Ranger was rated at 150 HP/185 lb.ft peak...at ~1650 rpm, the ecoboost makes almost as much as the vulcan did at peak...at 2000 rpm it makes more torque than the old SOHC 4.0!

not worried in the least...

this is the first dyno graph that I’ve seen that shows Down to 1,000 RPM. The ones I’ve seen start at 2,000 and leave the torque and HP values as pretty big guesses.

if fact, the ones I’ve seen, I think, didn’t show much power Until about 2,200RPM.

Let me compare these.

 

[Big Blue]

OK OK! I know I said I was backing out of this thread. But, I have been following to see where it would go. As I expected it has devolved in to an argument and culture bashing.

MHO the moderator needs to shut down this thread and ban Devil6! Who obviously does not own a Ranger, does not plan on owning a Ranger, loves starting arguments, and hates Americans.

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