The Lexus GS450h motor

As I recall, Damien knew of another guy who reverse engineered it, but he was unwilling to share any of the details or knowledge gained from that.

I might be confused on all his projects but I think the Bexus right now is unmodified. You (or I) might be thinking of another vehicle he's been working on using the gearbox, that he bought cheap, sold the motor for more than he paid for the vehicle, and did a full conversion.

Far as I know Damien and Kevin bought the Bexus Lexus it last month in England for 500eu (dead hybrid battery) and drove it back to Ireland, and just got it road-legal in Ireland (as a factory Hybrid).

The Bexus is being saved for one of the classes at Kevin's shop that Damien runs monthly (it's an advanced class scheduled for the summer I believe). They are going to do a 1 weekend conversion class and use it as the demo.

The goal is basically, engine out, more batteries in, and de-hybridizing the 10,000,000 dead-ish hybrid vehicles in the world.

The GS540H has seen a lot of interest lately, within the last year, and, as things take time, I'd expect to see a lot of conversions get finished this year using them. The trend seems to be Prius's for FWD conversions and Lexus's for RWD and higher power conversions.

I've been following Damien Maguire's many videos on Youtube for the last couple of years since he was working on his EV BMW 840 coupe.

Since, I've been looking into many motor and controller options for a mere 200hp, 250hp or 300hp without blowing any many transmission gears to smithereens and without spending $20k on the swap motor alone even before the other required hardware and batteries.

His continued progress on the GS450h transmission has intrigued me with its nearly 250hp potential once the input shaft is locked and the controller is sufficiently tricked into running the MG1 and MG2 motors simultaneously.

I've never heard him talk about the torque but I assume in this configuration it would need to go onto a dyno to properly measure the true output from MG1 and MG2 combined. I could be wrong but I think Toyota might only have officially stated the MG2 (output) motor torque and power while the MG1 was not considered by Toyota engineers to be a main drive power source.

Still... as it stands it's looking like a great package no matter what.

I've just completed an SC300 5-speed turbo project and now I'm eyeballing this to go into an IS300 (sedan or wagon) or FR-S. I'd prefer manual gearing to be retained but as a complete package this is hard to beat in a commuter EV that could be used every day in traffic.

After doing a little research into the Lexus GS450h it seems to have come with a 3.769:1 rear differential as standard and with its unique transmission will go to 155mph.

Therefore any RWD donor vehicle which can get a 3.7x:1 ratio rear axle into it or close to that (3.9x:1, etc.) should retain the same top end characteristics gearing-wise.

Even with the a pack voltage lower than Damien's stated 400v in his "Bexus" (or was it 450v?) I still think it would cover all bases for moderately powered compact RWD and even some large RWD conversions.

In really lightweight RWD donor chassis (FR-S, Miata, small 60's-80's RWD cars) it would be an amazing power and torque output combination for the money.

DrGee said:

It will be interesting to see if de-icing hybrids becomes a trend.

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There are 8+ classes scheduled for the next year, 10 participants each, $1000/per person. Plus they're in Ireland and almost all participants are flying in from around the world.

Previous participants have already started manufacturing adapters to lock the gearboxes so they can be ran as EVs.

I think it's certainly the new meta for EV conversion parts, why buy a $200 forklift motor and then spend $1000 on a controller when you can buy a $1000 pre-engineered drivetrain with matching inverter?

But just keeping the hybrids as-is seems to be a popular idea too.

cinephile said:

I've never heard him talk about the torque but I assume in this configuration it would need to go onto a dyno to properly measure the true output from MG1 and MG2 combined. I could be wrong but I think Toyota might only have officially stated the MG2 (output) motor torque and power while the MG1 was not considered by Toyota engineers to be a main drive power source.

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MG2 is the drive motor.

MG1 is to start the engine and to do regenerative braking.

However, MG1 is usually ~2/3 the size of MG2, and if you axe the engine, no reason you can't drive both motors to propel the car down the road.

drother said:

There is some debate whether its 10,000 rpm or 14,000 rpm.

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If it's like the Prius, it'll depend on year.

1st gen is like 6500.
2nd gen is 10,000.
3rd gen is 13,500.
4th gen is 17,000.

Ditto for whether you can lock the input shaft or have to weld the planetaries. In the Prius 3rd gen and onward, there's a second set of planetaries for MG2 and you can just lock the input shaft.

In any case, no one needs to be or ever will be travelling 156mph in a goddamn Lexus. Or 114mph. Moot point.

...

In other news, there's also the Toyota AWD models, which have a cute little ~100 lb rear end that has a supplementary motor in it. Probably good enough for light use on light old car conversions but not enough for anything sporty.

MattsAwesomeStuff said:

MG2 is the drive motor.

MG1 is to start the engine and to do regenerative braking.

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No, that would be using MG1 like a mild hybrid system, and MG2 like an unrelated parallel hybrid on the same vehicle, and ignoring the critical power-split planetary gear set.

The power-split planetary gear set means that the speed of MG1, combined with road speed, determines the engine speed; MG1 is run at whatever speed is required and its power is a result of that speed and the torque required to balance engine output torque.
The operation of MG1 can produce or consume power; whatever it does, MG2 complements it in steady-state operation (plus or minus whatever the control system decides to pull from or return to the battery). So if MG1 is generating, MG2 is motoring, and the flow of power from the engine to the wheels is split between a mechanical path and an electrical path. In a range of road speed and engine speed combinations the power is actually from MG2 to MG1, so power is recirculating (mechanically from engine to wheels with some looping back from MG2 to MG1).

If the engine is idling then MG1 is just spinning with minimal torque, which means that for normal regenerative braking it is all done by MG2.

MattsAwesomeStuff said:

However, MG1 is usually ~2/3 the size of MG2, and if you axe the engine, no reason you can't drive both motors to propel the car down the road.

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I agree with that part: a simplistic EV operation which wastes one motor, much of the transaxle, and one section of the controller/inverter would be to just use MG2, and that would work (and is how the hybrid works in EV mode, because MG1 can't be used without operating the engine). A better EV operation would use MG1 as well, logically by locking the power split gearset so that MG1 and MG2 speeds are synchronized; my understanding is that this is the conclusion already reached by many builders as discussed earlier in the thread.

The relative sizes of MG1 and MG2 in power-split hybrids depends on the modes supported (Toyota uses only input power-split, but GM and others have used additional modes including output power-split, and dual split) and gear ratios between components (the extra multi-ratio transmission between MG2 and the wheels of some later Toyota hybrids - the GS and LS variants - allows more optimal operation of both motor-generators, but to different extents). MG1 is usually substantially smaller, but it's still a significant motor.

If you want a challenge, try to follow all of the modes of a Gen 2 Volt (the 5ET40 transaxle) or the old 2-mode transmission from GM pickups and SUVs (the 2ML70) and similar transmissions from BMW and Chrysler.

I found the following buried on an OpenInverter forum post. I'll add it here in case someone else is searching too.


Overall height (oil pan to top of bellhousing) is 39cm. Bell housing is full height, i.e. 39cm diameter, when the transmission is sitting on its oil pan (as it is on my bench), the bellhousing still just about touches the bench.

Widest point is 40cm, includes a bump for a starter motor which I don't believe the GS450h even has. Likely leftover to mate with the 2GR engine.

Overall length including tailshaft, output flange, and pilot shaft, is 82cm.

Transmission is tapered quite heavily, the width and height is closer to 25cm after the bellhousing, but hard to gauge due to various outcropping parts (motor cables, oil pump, PRNDL selector, etc)

Weight feels like in excess of 100kg, I'd say closer to 120-150kg.


Source:
https://openinverter.org/forum/viewtopic.php?f=14&t=205&p=3542&hilit=gs450H#p3542