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Posted: Wed, 19 Nov 2014, 16:17
EV2Go wrote:Have you or any of the guys of the forums run any performance formulas?
Happy to give it a go.
Found the torque/speed graphs here:
https://www.industry.usa.siemens.com/dr ... sheets.pdf
Main one of interest is this:
1. Finished car estimated weight.
2. Total drive line ratios (multiple gears takes a while to figure - woody might try this I haven't ever had to).
3. Estimated wiring resistance - including contactors and fuses. Not that important and probably swamped by other variables anyway.
Edit: Also tyre size.
Posted: Wed, 19 Nov 2014, 16:49
EV2Go wrote:I am actually looking forward to seeing how well it goes, based on the batteries, controller and motor it should go half decent. Have you or any of the guys of the forums run any performance formulas?
I have a spreadsheet at home which I did some calculations on. I'll post up my figures later tonight.
Johny wrote:Happy to give it a go.
Cheers Johny. I'm keen to see what other people's calculations would be.
I've based my calculations on a finished weight of 1250 kg and the drive line ratios are as follows:
- First Gear: 3.287:1
- Second Gear: 2.043:1
- Third Gear: 1.394:1
- Fourth Gear: 1.00:1
- Fifth Gear: 0.853:1
- Diff: 4.11:1
Standard wheel size is 14 inches with a 185/70 tyre.
Posted: Wed, 19 Nov 2014, 19:14
Ok - preliminary figures. I may have missed something big in which case these are rubbish. I had to fudge a lot to get reasonable figures.
1st gear 00-30km/h 0.5 Sec
2nd gear 30-60km/h 1.3 Sec
3rd gear 60-100km/h 3.8 Sec
Total 5.6 Sec
Doing the whole 0-100km/h in 3rd gear is 5.9 Sec.
So since the gear changes will take precious time, 3rd gear straight may well be faster.
Also accelerating a two wheel drive from 0 to 30 km/h in 1/2 second may be tractionally impossible.
It looks a bit too good to be true...but weight is playing a bit part.
I reserve the right to delete this post when I find out where I embarrassingly went wrong,
Edit #1: Corrected table for 150kW maximum out of motor (I had 200kW)
Edit #2: Evaluated motor power in field weakening range better (spreadsheet was giving errors so I had extrapolated [incorrectly] - sorry)
Posted: Wed, 19 Nov 2014, 19:29
See previous edited post.
In addition doing the 0-100km/h run in 2nd gear yields 4.2 seconds (Edit: not right but I'll leave this for now).
I will continue to edit the previous post as I find errors.
Refresh your browser.
Posted: Wed, 19 Nov 2014, 20:20
At those figure levels I suspect traction will be a factor too
Posted: Thu, 20 Nov 2014, 00:13
Thanks for the calculations Johny.
My napkin workings at home have it at a conservative 5.79 seconds to reach 100 km/h using second gear alone. I say conservative as I tend to err on the side of caution when doing calculations and generally use the worst case scenario values (in this case using lower torque at wheel values) - I find this gives me a better margin for error. If I use the best case scenario torque at wheels value I get a result of 2.42 seconds.
As both Richo and yourself point out, I think I'll have traction problems before I reach those kind of acceleration times.
Posted: Thu, 20 Nov 2014, 03:07
Still respectable times for an EV.
Posted: Thu, 20 Nov 2014, 03:12
Yes I doubt that a gearchange would be helpful unless you could tie motor speed into intended target gear. Probably faster to stay in 2nd.
Posted: Sun, 21 Dec 2014, 00:04
Put together the motor, adapter and gearbox last weekend for the first time. Everything seems to fit together nicely.
I had to have 0.19 mm taken out of the hub to fit the clutch pilot bearing as the fit was too tight.
Here's a picture of the first fitting in the engine bay:
I'm going to need to rotate the DE plate 90 degrees to allow the motor to mount lower in the engine bay as it currently sits slightly too high and lowering it any more in the current position fouls the steering components. Other than that it fits well.
Nexts steps are to measure up some engine mounts and clean the engine bay.
Posted: Sun, 21 Dec 2014, 01:31
Posted: Sun, 21 Dec 2014, 01:59
Very nice Chris! Very neat fit too.
Posted: Sun, 21 Dec 2014, 14:01
That motor looks like such a brute, dominating the relatively puny gearbox! (My apologies if I have misunderstood.)
I just hope all that motor torque will play nicely with the rest of the drivetrain.
Posted: Sun, 21 Dec 2014, 15:52
Adverse Effects wrote:
Agree just needs some polished alloy to make it really bling
Posted: Sun, 21 Dec 2014, 17:57
Cheers guys. Yes it's definitely looking the part.
Regarding the driveline longevity and the amount of torque available, the Toyota W series gearboxes are well known for their strength but I do expect I'll be stretching the friendship if I don't treat it with respect. I have a stronger (and lighter) W55 gearbox ready just in case. Albins also make a straight cut gear set for the W55 should I find the need. I expect that if anything starts to complain it will be the diff first. I'll cross this bridge if/when I come to it but there are plenty of options with arguably one the strongest being a Hilux diff.
Posted: Sun, 21 Dec 2014, 21:03
That driveline looks awesome.
But the fuse in the circuit will definitely be the diff...
Posted: Tue, 23 Dec 2014, 02:38
Is this the same 5 sp they used with the 18RG twin cam eng? The strengthen fix for them was fitting the BMW (I think it was 13 ball) bearing to the front of the cluster gear, it can be done without stripping the gearbox with a suitable brg puller but they are not that hard to strip anyway.
Posted: Tue, 23 Dec 2014, 04:13
It could be the same gearbox as they used both the P51 and the W50 gearboxes behind the 18R-G engines. I'm not entirely sure of the physical differences between the P51 and the W50 but I believe the W50 was the stronger of the two. Given that the P51 was built by Porsche/ZF it would be feasible that this is the box they strengthened with a BMW bearing.
Re: TooQik's Celica
Posted: Sat, 11 Jan 2020, 00:29
Did you ever finish this project?
Re: TooQik's Celica
Posted: Mon, 20 Jan 2020, 12:58
Sorry for the delayed reply.
Unfortunately it's still on my to-do list, as life keeps getting in the way.
If nothing else, it's a good self discharge test for the batteries.