Know thy enemy, right?

I'm seeing and hearing conflicting information about what's included in Defender's power plant. The only information from JLR is... a bit on the marketing side.

All right, so P300 and P400 are turbocharged. V8 is supercharged. Enter MHEV.

On one side, I was told (and it feels like) that this is an extra electric motor that can give the ICE a boost when necessary. On the other hand, I just heard from someone that is supposed to know what they're saying that MHEV is, quote, "simply an electrically driven supercharger" (which also mirrors an article I read when I was researching the topic for the first time - and that article also glazes over it, "...dual forced induction and electric assist").

Then, the Wiki MHEV article mentions dual hybrids which also makes perfect sense - however, I've never heard this term applied to current Defender engines.

So, which is it? Just the extra motor? Electric supercharger? Or both?

...and how does "extra powerful battery" go together with complaints about the electrical system being inadequate that I see here pretty often?

 

In the case of the Defender it is an electrically driven supercharger that is supposed to fill the gap of turbo lag until the turbo spools up. It isn’t a drivetrain in this application. This is my understanding from what I’ve read.

 

My understanding, also. All my previous reading on the subject does not mention an ‘electric’ drivetrain like one would expect in a true hybrid, having both a petrol engine AND an electric motor-driven drivetrain. If there is more info on this I am curious as to its nature, too.

 

Let me add some oil to the fire - did you ever notice how P400 starts instantaneously, unlike just about any traditional engine on the market? I'm not sure just having electrically driven supercharger will allow that, but then again, what do I know.

 

Found this:

MHEV Meaning

MHEV stands for Mild Hybrid Electric Vehicle. As implied by the MHEV meaning, these vehicles feature an innovative hybrid powertrain which includes a small electric battery that feeds a low-output electric motor to help the gasoline-powered engine work more efficiently. An MHEV charges itself by using a regenerative braking system that recovers the kinetic energy created by hitting the brakes. This energy is transformed into electricity and stored in the battery. Unlike a PHEV, an MHEV cannot run on electricity alone. Nevertheless, you’ll enjoy enhanced fuel efficiency with vehicles like the Range Rover MHEV, the Discovery MHEV, and the Defender MHEV, meaning you’ll save on those costly fuel-ups at gas stations.

 

Yea, that's cool. It just sort of explodes to life right away. I like it. Feels very premium and swift.

Sometimes though the starter does crank like a standard car (like if the car has been sitting for awhile, a week, sometimes even if a few hours).

One of the things all the pressers say about the new 911 992.2 GTS is that it doesn't crank over like a normal car. I have to laugh because our Defenders been doing that for 4 years!

 

That's where I started, and that's exactly what I meant when I said "a bit on the marketing side".

innovative
small
help
efficiently
enhanced

No numbers, just "power words" (cue Taking Care of Business and Jim Belushi reading the page from the Filofax).

I guess I'll just have to drill it down. Related question, where do I go to do that?

 

...along with extremely fast first to second switch on acceleration from stationary. Being a stick driver, I do pay attention to shifts, and that blew me away.

Wild tangent - I'd love to have the shifter paddles that I grew to love on my other cars, but well, P400 is the first automatic out of those that I drove where shifting is probably irrelevant...

 

But - where is the motor? I'm skeptical on this explanation as I don't see any evidence of secondary traction power with a motor

Would love to know if this is true - the boosted supercharger sounds more plausible to me. But - I'm speculating..

 

For P400 -- https://www.caranddriver.com/news/a2...ne-six-engine/
sort of explains it.

I agree. Very much a mystery.

Two electric motors it sounds like? I am no engineer but here is how I understand it.

1) BISG (belt integrated starter generator). Sort of like a starter motor and provides the startup/start-stop function and mysteriously, apparently this thing helps goose the engine as well via electric assist. I admit this part is very unclear to me.

2) The Supercharger is electric (ie it has an electric motor, it's not forced induction -- that's saved for the turbocharger).