High rpms

Gang, I hear often "low end torque". Why not let her reach higher rpm? Engine produces maximum torque at 2500rpm, why? I think it's very bad!

 

Why? Bettuh for pulling stumps out of the backyard.

 

And your other posts:


Maybe the truck is eating bearings and can't make enough power to request higher boost due to friction? I doubt computer would pick up worn bearings; probably just thinks you are too heavy all the time?

Edit: Or maybe...[conspiracy theory] there *is* a bearings health sensor and computer is limiting boost to save the engine past warranty so it doesn't grenade itself too soon?



They finally figured it out!

I've scrubbed through reddits and there are no more problems with third generation toyota tundras.

They're finally safe to buy!

 

Gang, you can go defending 3rd gens in 20205 engine down thread, I here asked question about rpm's. If you dont know the answer, sit next to me, and we will both wait for smart person to explain to us.

 

Umm, it’s a truck.

 

Torque gets you moving and horsepower keeps you moving. Which engine are you referencing?

 

If this is an honest question, the answer is simple.

For a truck doing truck things, like towing and hauling heavy loads, low RPM torque is always best. It puts less strain on the engine and drivetrain.

The goal for a useful truck isn't to set records at the race track.

 

Thank you, both. I'm trying to understand why tin turbo v6 in new tundras has such low peak torque? Does this mean acceleration starts to taper off if you start reaching beyond 2,500rpm? Maybe i'm being confused by ignorance(lack of knowledge?)

In mine, from a while back wot, it almost feels like acceleration wears off as youre reaching 5,000rpm. It almost sounds like engine is yelling, but it's useless at that point. Does the ease thing occur in newer tundra engines after you get past like 3,000rpm?

Again, this is just curiosity inside me.

 

I’ve already done the high RPM thing. I did that towing in my 2013 5.7 Sequoia over mountain passes and various highway grades with the RPM at 4,500 and above for long, steady climbs. And with a plan of where I can fill up with gas next.

 

The Bore and Stroke help determine what range peak torque happens at. Like I said torque will get you off the line but horsepower determines when your engine runs out of steam and at what rpm. Other factors contribute to when peak horsepower happens and when an engine runs out of power as well.

 

So, I've been scratching my braincells together in the shower and here's what my thinking is: bore is how wide cylinder is and stroke is how far cylinder has travel, yes? So, if both motors are for example 3.6L, they can behave wildly different if one has wider bore and shorter stroke vs the other having narrow bore and long stroke?

The reason 3rd gen motor has low rpm torque is due to narrow, but long cylinders? Or does turbocharging mainly come into play here?

Thanks gang.

 

I know this one!!!! The answer is: it has low RPM torque because it can.

 

Torque wins races, Horsepower sells cars.

 

Both the turbo and the bore/stroke ratio. The small bore / long stroke is called undersquare and is great for torque, not so much for high rpm’s. IIRC the 3.4 in these trucks are more undersquare than 6.7 powerstrokes (ratio of stroke to bore is bigger on the 3.4s than the 6.7). The small turbos on these guys spool up to ~6psi under 2k rpm under normal acceleration in my experience.

 

Also, whatcha mean by “has low rpm torque”. All trucks have low end torque— so what’s your point?

 

WELL I DONT KNOW!!!!

I was driving home and passing a car and rpm'ed to 3,000 and remembered how many guys say here, or some say here that 3rd gen motor has lots of low end torque. So, I thought to myself, is the only useful range of rpm's under 3,000? Because, from that statement, it seems like you can tap all of engine's power under 3,000 on tachometer. It had me puzzlee why more rpm is even needed then? Hence, this thread...

Please sorry for my lack of kn9wledge.

 

Well heck I can answer that question too!!! It’s a useful range, and then when it isn’t the transmission finds a useful range. Not much has changed about that. I mean, I should add, that this happens >95% of the time, the rest of the time, whatever the exact percentage is, something might have happened to the engine and it’s broken.

 

So if and elephant hits a wall at 60 mph. How far he moves wall is torque.

If a fly hits the wall at 60 mph. How far it moves the wall is torque.

Sooner torque comes on in rpm range the more pulling power and how fast you get up to speed.

Cubic inches build more torque in lower rpm range with right sit up.

More the cubic inches sooner you can build HP and torque and also more.

For a typical 300 cubic engine to make 300 HP it could do it in lower rpm range say around 5500 rpm.

For that same engine to make 500 HP it would have to turn around 7500 rpms estimate.

Give them some boost or NOS or blower then it all comes on sooner with that little engine.

Hope that helped.

 

Thank you. I will try to digest this overnight and see if I can make complete sense of it.

(I am sorry,but I have this sort of quirk with my brain. Sometimes, I cannot understand certain simple thing, until it clicks)

Thank you again for taking the time to sort this out.

 

Simpler terms.

Smaller sprocket on a bicycle lets you take off faster. less top end. More torque.

Bigger sprocket on a bicycle you take off slower, but you have more top speed. Less torque more horsepower.

That either mudded water or it helped.

@EmergencyMaximum

 

https://youtu.be/9icuIqQ_zCM?si=BYAguSFlBlJQiylV

 

This is the best and most simple answer. I'd MUCH MUCH rather have maximum torque at lower RPM'S than having to make the engine scream to get things done.

 

It's really nice to hold this engine at 2400 rpm and know it isn't going to do any more than that even if you push it.
It could run there forever. Anything more is just wasted fuel, noise, and wear-n-tear.
Just like most big diesel engines, a few thousand RPM is going full bore.

 

Torque is the winner of the game in 99.75% of all cases. When you can reach that power torque lower, as said it is much easier on the motor and transmission.

Forced induction motors always build more torque and at lower RPM's. The TT V6 in the gen3 Tundra is a very well designed motor (IMHO). I have been very pleased with it to perform as smooth as it does.

Instead of knocking the gen3, people should consider test driving one. You will see why we love them !

 

I do not think your statement is true. High torque at low rpm’s puts more friction and strain on the bearings. At higher RPMs with the same load, the main bearings have less strain and are better lubricated. I’m referring to high torque load around 1.5-2k rpm (low) vs say 2.5-3k rpm for the same load. Again, just my opinion, but do your own research.

 

Wrong. Here's Google's AI explanation. it's not always correct, but it is in this case.

How low-end torque helps reduce strain:

• Reduced RPMs:
  Engines with good low-end torque can perform work, like accelerating or towing, at lower RPMs than engines with less low-end torque. This means the engine is working less hard, potentially reducing wear and tear.
• Efficiency at low speeds:
  In stop-and-go traffic or when climbing hills, low-end torque allows for smoother acceleration and reduces the need for frequent downshifts, which can put extra stress on the engine.
• Reduced stress on components:
  Because the engine isn't constantly being revved to high RPMs, the various components like pistons, connecting rods, and bearings experience less stress, potentially leading to increased longevity.

 

Everything bout the 3.4 V6 is designed for low end torque. From the under square bore, the tiny turbos mounted very close to the exhaust valves, the low volume air to liquid intercooler, the intake valve angles, dual injection, short intake runners and more. I am coming from an ECO Bost with slightly more HP but much higher revving. Sporty driving or heavy towing the toyota feels stronger while having about 50 HP less than the ECO boost. Now if they can just fix the jumpiness off idle i will be totally satisfied.

 

Back in the day and still, I've always been a huge Pontiac fan for this very reason. They were perfect low end torque monster engines. A standard 455 would make 455lbs. Of torque at just 2800 rpms. Perfect for big heavy cars, no need to rev.
Meanwhile, the small block chevy guys were screaming to the moon for power.
Nothing against that, they are all good engines, just designed different.
Low end grunt is best for pulling, towing, hauling, etc. Thats the very reason diesels do so well.

 

I got spoiled having 1400 ft lbs of pure insanity at like 1600-1700 rpm haha.

on the last Cummins build I could lock it in 4wd, do boosted launches at 15-18 psi and chirp the tires going into 2nd.

it would run low 11s in the qrt turned up but hell on driveline components. Super fun though!

I can’t stand high reving engines, I want all the power under 3k max if available. These 3rd gen’s are the closest gas trucks to diesel in that regard. I had 23 2.7 ecoboost and much prefer the powerband of the tundra compared to it. These trucks tow amazing for a 1/2 ton.