Long Stroke vs Short Stroke 4x4 Engine, Why?

[Herbie]

Maybe it's just me, if you're down to sweating the details of an over- or under-square engine in your rig, you've officially run out of things to geek out about and should probably just go camping.

Or more accurately, that's not a detail that's likely to make me pick one rig over another.

 

[Pskhaat]

Your LC's are good examples of this, they are well balanced V8's that travel well offroad....they are not high torque reserve engines but have a wide usable powerband.

Again, we may be arguing subjectivity here. I do not think the Toyota V8s (2UZFE) are good choice for the LandCruiser. Not at all. In my biased opinion, Toyota did this to sell a "V8" engine name to gasoline-thirsty consumers. One can easily tell driving as well as towing how high this notorious curve is, even compared to the older (1FZFE) US engines. And of course, these are puny automotive engines. Being in the US, I have had to compromise on the LC engine whilst still enjoying the brand. I will say the 2UZ-FE has been unexpectedly and surprisingly reliable.

I think you want a wide HP "curve".

No

If you swapped in a low RPM diesel into your cruiser with the same torque value, which will have more torque rise, I highly doubt you'd be happy with it's overall performance

On the contrary, a 4BT-swap Cruiser is ideally what I personally would want, and one of my favorite powertrains. Alas, I'm not a fan of swaps and the associated gremlins, and thus the aforementioned compromise. I will concede that you said "overall performance" and that includes fast highway/pavement; hard to argue against the need there.

I'm curious when overstroked vs overbored became terms. I always used oversquare, square or undersquare.

At Uni I was a mining "automotive" (mechanical) engineer working on both heavy open pit equipment engine design (we were all moving hybrid) as well as on electric drilling jumbos. We used those overbore/overstroke terms ~30 years ago, but I've heard it both ways.

I will take a wide linear powerband over peak torque any day. ... Torque is a spurious measurement at best. Horsepower (kw) is the true measurement, and is a combination of torque times RPM.

Again, totally cool, but not my own preference. I might mathematically counter that HP is nothing more than a linear time factor applied atop torque. Torque being the true measurement. I am going to assume a bit, but most folks in the overlanding world (?) are focused on meaningful mechanical work, and not necessarily the power (how much (less) time it would then take). 90bhp/67kW with torque in the ++160lb-ft/217Nm arguably performs beautifully well in the bush, and downright annoying at very best on the highway!

But seriously how many of us would kill to drive this beast as-is:

​

 

[Pskhaat]

...if you're down to sweating the details...should probably just go camping.

Heck yes. Need to win that lotto soon, get out behind this desk and live more!

 

[nickw]

Again, we may be arguing subjectivity here. I do not think the Toyota V8s (2UZFE) are good choice for the LandCruiser. Not at all. In my biased opinion, Toyota did this to sell a "V8" engine name to gasoline-thirsty consumers. One can easily tell driving as well as towing how high this notorious curve is, even compared to the older (1FZFE) US engines. And of course, these are puny automotive engines. Being in the US, I have had to compromise on the LC engine whilst still enjoying the brand. I will say the 2UZ-FE has been unexpectedly and surprisingly reliable.



No



On the contrary, a 4BT-swap Cruiser is ideally what I personally would want, and one of my favorite powertrains. Alas, I'm not a fan of swaps and the associated gremlins, and thus the aforementioned compromise. I will concede that you said "overall performance" and that includes fast highway/pavement; hard to argue against the need there.



At Uni I was a mining "automotive" (mechanical) engineer working on both heavy open pit equipment engine design (we were all moving hybrid) as well as on electric drilling jumbos. We used those overbore/overstroke terms ~30 years ago, but I've heard it both ways.



Again, totally cool, but not my own preference. I might mathematically counter that HP is nothing more than a linear time factor applied atop torque. Torque being the true measurement. I am going to assume a bit, but most folks in the overlanding world (?) are focused on meaningful mechanical work, and not necessarily the power (how much (less) time it would then take). 90bhp/67kW with torque in the ++160lb-ft/217Nm arguably performs beautifully well in the bush, and downright annoying at very best on the highway!

But seriously how many of us would kill to drive this beast as-is:

View attachment 555498​

Have you driven a 4BT? Besides netting better gas mileage it's not going to make a vehicle any more "capable", the V8 in your cruiser has more than enough power, just off idle, to power your rig in 4x4 low range over anything it it's way.

It's also why the factory diesel engines in the Toyotas were never crazy high-torque low RPM industrial monsters, you still a wide HP spread to get around effectively. Toyota could have easily thrown a small high torque reserve engine in their cruisers but opted not too....same for Mercedes and Nissan. You still need HP and RPM.

I do think that 200Tdi would be sweet but would take the Toyota 2F in my old Cruiser over it, more HP over a more usable range.



My guess is also that my 2019 Ranger with it's 2.3 Ecoboost (now that I have driven it extensively) probably has more torque at the same RPM as the 200Tdi. It makes max torque of 310 ft/lbs @ 3000 RPM, certainly doesn't mean it doesn't make more than 195 @ 1800, based on how it drives, I'd believe it....although I have no data to back that up besides seat of the pants. Not that the ranger is unique in that, but just a personal example.

I'm sure my tone is argumentative, apologies. I do understand where your coming from. Rigs with lots of torque off idle with are easier and more manageable offroad in certain situation and do drive very nice. ?

 

[Deleted member 9101]

I prefer a square bore.

 

[Deleted member 9101]

My guess is also that my 2019 Ranger with it's 2.3 Ecoboost (now that I have driven it extensively) probably has more torque at the same RPM as the 200Tdi. It makes max torque of 310 ft/lbs @ 3000 RPM, certainly doesn't mean it doesn't make more than 195 @ 1800, based on how it drives, I'd believe it....although I have no data to back that up besides seat of the pants. Not that the ranger is unique in that, but just a personal example.

Add a tune and a down pipe and you will see how that 2.3 should have come from the factory

 

[nickw]

Add a tune and a down pipe and you will see how that 2.3 should have come from the factory

Roush has a tune that matches the factory 3/36 warranty, + 56 ft/lbs and + 14 hp max....not sure it makes sense since I'd be more interested in having more power between 1500 to 3000 but tough to ascertain from the dyno graph how much more you get lower in the RPM band. Regardless, 285 hp and 365 ft/lbs are solid numbers.

2019-2020 Ranger 2.3L ROUSH Performance Pac - Level 1

The 2019-2020 ROUSH Level 1 Ranger Performance Pac for the 2.3L EcoBoost® engine has been engineered to deliver trademark ROUSH power and performance in an easy-to-install kit. Designed to offer increased power gains and engine performance, the Level 1 Performance Pac has been extensively tested...

www.roushperformance.com

Tempting.

 

[Deleted member 9101]

Roush has a tune that matches the factory 3/36 warranty, + 56 ft/lbs and + 14 hp max....not sure it makes sense since I'd be more interested in having more power between 1500 to 3000 but tough to ascertain from the dyno graph how much more you get lower in the RPM band. Regardless, 285 hp and 365 ft/lbs are solid numbers.

2019-2020 Ranger 2.3L ROUSH Performance Pac - Level 1

The 2019-2020 ROUSH Level 1 Ranger Performance Pac for the 2.3L EcoBoost® engine has been engineered to deliver trademark ROUSH power and performance in an easy-to-install kit. Designed to offer increased power gains and engine performance, the Level 1 Performance Pac has been extensively tested...

www.roushperformance.com

Tempting.

Roush is nice...but companies like Brew City Boost will do a custom tune that will safely make more power.

 

[billiebob]

almost every engine, gas or diesel, horsepower peaks near redline, torque peaks in midrange.
with a class 8 engine horsepower might climb to 600 HP at 2200rpm.
but torque will plateau at 1800ftlb at 1600rpm, slowly dropping off as you accelerate.
so when cruising at 2000rpm and entering a 10% grade as the rpms fall, the available torque increases til you hit 1600rpm.
and the quickest way to climb that grade is to keep the rpm between 1500rpm and 1900rpm.

Diesels live for mid range rpms because they make way more torque than HP.
But gas engines perform best at redline since they make so much less torque.

 

[nickw]

nope

almost every engine, gas or diesel, horsepower peaks near redline, torque peaks in midrange.
with a class 8 engine horsepower might climb to 600 HP at 2200rpm.
but torque will plateau at 1800ftlb at 1600rpm, slowly dropping off as you accelerate.
so when cruising at 2000rpm and entering a 10% grade as the rpms fall, the available torque increases til you hit 1600rpm.
and the quickest way to climb that grade is to keep the rpm between 1500rpm and 1900rpm.

Diesels live for mid range rpms because they make way more torque than HP.
But gas engines perform best at redline since they make so much less torque.

That is not correct.

The available torque increases as the RPM drops and it maintains a reasonably flat HP curve as to not fall off nor require the driver to shift down. But max HP is exactly what is going to propel your output shaft, through your *transmission* and back to your differentials and move you. A vehicle will absolutely go up a hill quicker at max hp vs max torque, unless they are the same which they certainly can be in some low revving applications.

Your missing the *gearing* component. There are of course gearing limitations which is why tractor trailers need a relatively wide / flat operating range as there is not a perfect gear for every situation and it needs to be flexible enough for max towing ability (max HP) and max fuel efficiency (lower RPM) and does need to account for lugging without the required shift. But for max performance, run her at max rated HP.

Doesn't matter if it's diesel or gas. Limitations obviously apply when considering running a gas engine at max HP for extended periods of time since they are not "rated" to do that like a diesel engine is.

Hook up a Corvette engine, a class 8 cummins and a 50L steam locomotive up to a generator, assuming they all produce 500 HP......the cable out the back powering a large electric motor won't know the difference between the engines, it's the easiest way to visualize it.

 

[billiebob]

That is not correct.

The available torque increases as the RPM drops and it maintains a reasonably flat HP curve as to not fall off nor require the driver to shift down. But max HP is exactly what is going to propel your output shaft, through your *transmission* and back to your differentials and move you. A vehicle will absolutely go up a hill quicker at max hp vs max torque, unless they are the same which they certainly can be in some low revving applications.

Your missing the *gearing* component. There are of course gearing limitations which is why tractor trailers need a relatively wide / flat operating range as there is not a perfect gear for every situation and it needs to be flexible enough for max towing ability (max HP) and max fuel efficiency (lower RPM) and does need to account for lugging without the required shift. But for max performance, run her at max rated HP.

Doesn't matter if it's diesel or gas. Limitations obviously apply when considering running a gas engine at max HP for extended periods of time since they are not "rated" to do that like a diesel engine is.

Hook up a Corvette engine, a class 8 cummins and a 50L steam locomotive up to a generator, assuming they all produce 500 HP......the cable out the back powering a large electric motor won't know the difference between the engines, it's the easiest way to visualize it.

20 years around trucks and over a million miles in the mountains, I'm just going to quit.

 

[nicholastanguma]

I prefer a square bore.

Curiosity: please explain why?

 

[Deleted member 9101]

Curiosity: please explain why?

They are a "Jack of all trades" kida motor

 

[85_Ranger4x4]

Judging by your name....you get it....along with Marlin Crawler

I ripped out a peaky gotta-have-it-in-4lo- to-clean-tires V6... and put in what some call a peaky V8.

But... what is peaky in a F-150 is like a freakin diesel in a Ranger. Even with my mediocre low range (2:1) it is amazing what it will idle over. 2lo-3lo are great trail gears and I can hold it back with the brakes in 1lo when I get caught behind an automatic truck.


And when I get it on the highway I can wring it out like the Mustang engine that it is. I don't really care what the bore/stroke is, it has what I want where I want it and isn't just a luggo-matic tractor engine that can't take RPM.

 

[javajoe79]

When geared correctly, torque always wins IMO. Exceptions include race applications where you need the RPM to be competitive.