Mercedes T1 conversion [WIP]

[21j]

Hi All,
I am hoping to start a new project soon, and all going well I will post in the projects section.
I just wanted to get a few thoughts/advice on my project before I gather the required parts.

The project will be a Mercedes TN or T1 whatever you prefer to call it.
Predecessor to the sprinter. I want to keep it as basic as I can if that is possible. It is a basic van with basic electrics. I am intending to do a 4x4 conversion at the same time with a basic mechanical setup.

My initial thoughts are Lexus GS450h transmission and inverter. The transmission in the place of the existing gearbox. This should leave room under the bonnet for the inverter with zombinverter from Damien. Next for the charging, Tesla Gen 2 or use the inverter board?
Any recommendations for the DC to DC converter for the Aux battery and BMS?

Batteries for the motor - I am thinking I have some space under the bonnet for a small cuboid shaped battery from some hybrid, piggybacking off a main underfloor battery (from skateboard type design). May have to consider narrow width to go between the leaf spring mountings at the rear to avoid divorced transfer case in the centre.

If I take about 500Wh/km for the box shaped van (5m long) I think need about a 70kw battery to get about 150km range.

I know there are other ancillary items such as vacuum pump, heating etc, but i would just like to get the principal working first.

I would welcome any thoughts you may have on this proposal.

Thanks
john

[Jacobsmess]

Well this is fun. I have a mercedes T1 that I'm looking to convert using the GS450H also. Although the T1 was different to the T1N (early sprinter). I think they did the T1 up until 1994. Mines 1993 and a massive rust bucket!

[Jacobsmess]

If you want to do the 4x4 you'd be best off with a Subaru CVT or the LS600H as these both have transfer boxes. People have used Nissan Patrol axles to convert the T1 to 4x4 although if you're in the UK you need to be aware of the points system, if you change to electric as well as changing your axles, engine l and gearbox you need the original steering and suspension and no chassis modifications (including new windows/holes in the roof etc .) In order to avoid an IVA. Whereabouts are you based?

[janosch]

...
Next for the charging, Tesla Gen 2 or use the inverter board?
...

Most people fit an A/C charger, I am not aware of any projects apart from johu's Polo that used/are still using the inverter charging.
Correct me if I am wrong.

[21j]

Hi Jacobsmess,
We are looking at doing the same thing then.
I am based in Ireland. It is a T1 I want to convert. Circa 1994.
If I'm going the 4x4 route I'll be using a w463 divorced transfer box.
I believe the ratio of the transfer box is around 1:1 then I would have w463 axles that are 4.3:1.
Have you sized up the transmission yet and batteries yet.

Hi Janosch,
I believe you are correct. Thanks.

[Jacobsmess]

Hi Jacobsmess,
We are looking at doing the same thing then.
I am based in Ireland. It is a T1 I want to convert. Circa 1994.
If I'm going the 4x4 route I'll be using a w463 divorced transfer box.
I believe the ratio of the transfer box is around 1:1 then I would have w463 axles that are 4.3:1.
Have you sized up the transmission yet and batteries yet.

Hi Janosch,
I believe you are correct. Thanks.

I've measured for both the GS450H and GS300H transmissions and there's plenty of space for both.

[21j]

Thanks.
Where are you based yourself?
The 300h doesn't seem to have been tested much.
Does the 450h have 2 forward gear ranges and the 300h has 1?
Have you considered ratios of the diff and wheel sizes?

[Jacobsmess]

Yes I've considered it all, I'm based in Leeds.
The 450H has a high gear (3.9) and a low gear (1.9) whereas the 300H has a fixed ratio of 3.33. however gear switching on the 450H hasn't been cracked yet as far as I know.

The reasons I'd prefer the 300H are reliability, but the issues are speed, it is being put into vehicles ATM but you're right it's less tried and tested. It's also cheaper, lighter, more reliable and smaller which makes it very attractive to me.

One solution for using the 300H would be to change diff ratios as I think it's probably only able to achieve 12000rpm on a 400V battery pack, which tops out about 66mph in my setup (4.8 diff and 215/75/16 wheels).... Currently, on a good long run I can get up to 86mph... But it's noisy and drinks fuel.

[21j]

Thanks. I hadn't considered the 300h. Didn't realise there was a reliability issue with the 450h.
I was hoping to use the two gear ratios in the 450h.
Is it not just a manual selector between the ratios?

[21j]

I see now that it not manual

[Jacobsmess]

Thanks. I hadn't considered the 300h. Didn't realise there was a reliability issue with the 450h.
I was hoping to use the two gear ratios in the 450h.
Is it not just a manual selector between the ratios?

The oil pump is prone to failure on the GS450H and this can lead to self destruction. But people have worked around this by no locking the input and using mg1 to drive the oil pump. There has also been talk of using oil pumps from a BMW but I don't think this has been explored/developed.
That being said, I think people have not had any issues with it due to this this far.
It's not a manual control between the gears but solenoid controlled. You could probably drive around in high gear all the time however, I often set off in 2nd gear in my T1, even up hill and that's likely putting out around 2000nm to the wheels, the GS450H would likely be putting out around 2400nn in high gear with MG2 alone.

[tom91]

Your math is flawed.

MG2 is rated for 300 nm, high gear is 1.9:1 this results a prop torque of 570 Nm.
Your diff is 4.8, this yields a torque of 2700 Nm.

This is just MG2 torque and not accounting for anything from MG1. Please stop posting in correct things and creating a cloud of confusion around this.

Now for wheelspeed with your tire at 80 mph and the 4.8 diff you need 4500 rpm at the prop.

For the GS450h this means you need only 8550-9000 rpm in high gear.

[21j]

So from above if I wanted to travel at 80mph with 4.3 diffs, 1:1 transfer box and 30" tyres and GS450h in high at 1.9:1, The motor would be turning at 7200 rpm?
So for travelling up to a speed of 80mph from 0, the motor would be working from 0 to 7200 rpm. where does this range fit on the motor power/efficiency curve?
By the way, am I posting this in the right section of the forum? I could move it.

[Bigpie]

I've moved to Projects section for you.

[Aragorn]

Thereabouts yea.

A 30" tyre is doing about 900rpm at 80mph. 4.3 diff gear means the prop is doing ~3850rpm and thus the motor is doing ~7300rpm after the 1.9:1 reduction.

Seems to fit fairly well on the motors curve, a factory GS450h would be doing around 6500rpm at 80 for instance.

[21j]

Thanks, That's good news. I'm not a million miles away on the rpm then.

Any thoughts on the 4x4 setup with the gs450h. gs450h to G wagen transfer box to front and rear G wagen axles.
I want to keep it basic. I guess the gs450h has more torque than the gs300h but has the external oil pump.

I suppose I could also consider LS600h with AWD transfer case. Output shaft for the front axle would not suit the g wagen axles but ML 3.7 axles/subframe could be fitted, but will have to evaluate whether they can take 1.5 tonnes on each axle.

[Jacobsmess]

Your math is flawed.

MG2 is rated for 300 nm, high gear is 1.9:1 this results a prop torque of 570 Nm.
Your diff is 4.8, this yields a torque of 2700 Nm.

This is just MG2 torque and not accounting for anything from MG1. Please stop posting in correct things and creating a cloud of confusion around this.

Now for wheelspeed with your tire at 80 mph and the 4.8 diff you need 4500 rpm at the prop.

For the GS450h this means you need only 8550-9000 rpm in high gear.

I was accounting for drivetrain efficiency losses also, around 15% and rounding to conservative estimates. I don't think I've misled anyone, apologies if it seems so! I'm not sure where the cloud of confusion lies in what I've posted on the matter, only my own searching for information....

Let's not start arguements where there aren't any, that's for the DIYElectricCar forums!

[Aragorn]

Thanks, That's good news. I'm not a million miles away on the rpm then.

Any thoughts on the 4x4 setup with the gs450h. gs450h to G wagen transfer box to front and rear G wagen axles.
I want to keep it basic. I guess the gs450h has more torque than the gs300h but has the external oil pump.

I suppose I could also consider LS600h with AWD transfer case. Output shaft for the front axle would not suit the g wagen axles but ML 3.7 axles/subframe could be fitted, but will have to evaluate whether they can take 1.5 tonnes on each axle.

I would suggest, if theres a "traditional"/"tried and tested" method of using the Merc GWagen bits and a divorced transfer case, stick with that. Theres probably enough going on figuring out the electric bits, to also be figuring out a completely custom 4x4 system at the same time.

[21j]

Yes, that's what I'm thinking. Don't over complicate things.
Any thought on battery size and charging. If I take about 500Wh/km for the box shaped van (5m long) I think need about a 70kw battery to get about 150km range weather dependant. Chargers and converters? I'm open to suggestions.
I wont have any existing vehicle ECU taking signals from anywhere.

[21j]

With a 70kW battery (Actual 57kW) . (70kW * 90% = 63kW. Max discharge to 10% = 57.3kW).
I'm estimating
76 min recharge on 45kW charger.
491 min on domestic 7kW charger

but i guess this depends on the charger's fast charge ability.

[Aragorn]

Hard to be exact on range as it will vary wildly with driving conditions. I typically manage 3mi/kwh in my production EV, many other owners of the same car claim 3.5-4 or higher.

Reports from the production Ford Transit EV suggest circa 2.5mi/kwh is possible. F150 Lightning reviews suggest around 2.0mi/kwh

So thats probabaly a rough starting range.

[21j]

Thanks.
I was estimating around 150km based on 70kw battery and 500wh/km so that coincide roughly with the 2miles/kWh. I think.

[Jacobsmess]

I've been working on the basis of 1.5-1.75miles/kWh. My current diesel setup gets around 24mpg, (less when I drive too fast) which I've used to base my calcs on accounting for the equivalent energy per litre of fuel, however, a 4x4 will likely get worse milage. Re: the 4x4 conversion, I've not seen anyone actually do it with the Gwagon base. Whereas the Nissan Patrol I have. I think the Gwagon track width doesn't match the T1 whereas the Nissan Patrol Y61 (I think is almost a perfect match, which is why people have gone that route. There is also a 4x4 mercedes T1 axle set and transfer box for sale in the UK for around £6k if you're interested. I can forward the details.

[nkiernan]

Any thoughts on the 4x4 setup with the gs450h. gs450h to G wagen transfer box to front and rear G wagen axles.
I want to keep it basic. I guess the gs450h has more torque than the gs300h but has the external oil pump.

My project is currently based on a GS450H to divorced Magna Steyr transfer case to maintain the factory Range Rover four wheel drive setup. This hasn't been as straightforward as I was expecting (have to update project thread with latest mods). Now have the short drive shaft angle a lot better. But now that I've worked through that, I'd aim to go the centrally located rotated Tesla Model 3 rear motor route similar to how people are doing defenders. Much neater, more efficient, less potential problem areas. Just not open source yet...but its coming...hopefully I have a TM3 drive sitting in the garage to do that change over when it might be on the Zombieverter!

[21j]

I've been working on the basis of 1.5-1.75miles/kWh. My current diesel setup gets around 24mpg, (less when I drive too fast) which I've used to base my calcs on accounting for the equivalent energy per litre of fuel, however, a 4x4 will likely get worse milage. Re: the 4x4 conversion, I've not seen anyone actually do it with the Gwagon base. Whereas the Nissan Patrol I have. I think the Gwagon track width doesn't match the T1 whereas the Nissan Patrol Y61 (I think is almost a perfect match, which is why people have gone that route. There is also a 4x4 mercedes T1 axle set and transfer box for sale in the UK for around £6k if you're interested. I can forward the details.

Thanks.
It would just be the axles from the G wagen, not the base. Weld on leaf spring mounts etc. T1 4x4 had extended w460 axles. Same as w463.