I'm switching my diesel truck to Hybrid - Page 5 - DIY Electric Car Forums
Go Back  

DIY Electric Car Forums > General Forum > Chit Chat

Register Blogs FAQ Members List Social Groups Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #41  
Old 03-17-2017, 05:18 AM
CanadaLT28 CanadaLT28 is offline
Junior Member
 
Join Date: Oct 2011
Posts: 28
CanadaLT28 is on a distinguished road
Default Re: I'm switching my diesel truck to Hybrid

The front and rear diffs are the same ratios (obviously) so it must be that the 1:1 in high is for both and 1:2.7 in low is the same for both take offs so if the elect motor was put on the PTO for the front and only engaged in high, wouldn't that mean that the power would be transferred both to the rear wheels and to the tranny, which could be kept in neutral.

I used my brain a little bit more, lol. The above won't work. The front hub and input from the ICE will have to be switched. That is the only way to get the power from the tranny to the rear wheels.

Last edited by CanadaLT28; 03-17-2017 at 05:45 AM.
Reply With Quote
Sponsored Links
Advertisement
 
  #42  
Old 03-17-2017, 05:47 AM
dcb dcb is offline
Senior Member
 
Join Date: Dec 2009
Posts: 1,898
dcb is on a distinguished road
Default Re: I'm switching my diesel truck to Hybrid

if you turn the front shaft, the rear shaft had better turn 1:1 with it. The 2.7 is in regards to the engine vs BOTH shafts. And the chances of the motor spline just working is nil anyway. C'mon here.
Reply With Quote
  #43  
Old 03-17-2017, 05:53 AM
CanadaLT28 CanadaLT28 is offline
Junior Member
 
Join Date: Oct 2011
Posts: 28
CanadaLT28 is on a distinguished road
Default Re: I'm switching my diesel truck to Hybrid

Yes, that is what my edit said about the ratios.

I'm not sure what you mean by the "spline just working is nil anyway"
Reply With Quote
 
  #44  
Old 03-17-2017, 06:11 AM
dcb dcb is offline
Senior Member
 
Join Date: Dec 2009
Posts: 1,898
dcb is on a distinguished road
Default Re: I'm switching my diesel truck to Hybrid

too many rabbit holes here for me, let me know if you understand the coaxial sprocket concept with a motor chained off the side at the right ratio or not (it is not unlike a typical transfer case).

I'm begging off any other speculation with zero details to go off of and other misconceptions.
Reply With Quote
  #45  
Old 03-31-2017, 10:21 PM
brian_ brian_ is offline
Senior Member
 
Join Date: Feb 2017
Posts: 178
brian_ is on a distinguished road
Default Re: I'm switching my diesel truck to Hybrid

A series hybrid can only work better than a parallel hybrid if it has with sufficiently efficient generator and motor (which is rarely the case in these homebuilt conversions), and an engine sized appropriately for the application (not just the one that came in the non-hybrid vehicle).

Quote:
Originally Posted by dcb View Post
... ignore the real world evidence of conversion losses (including charging/discharging the battery) and of additional weight, AND THE FACT THAT NOBODY DOES IT THAT WAY!!!.
That's simply not true, as there have been series hybrids in production for years (mostly buses), and Nissan recently introduced a new one; however, parallel hybrids (and mixed-mode series/parallel setups such as the most common hybrid of all - Toyota's Synergy Hybrid Drive) are far more common, especially in light vehicles, for all of the reasons which have been described.
Reply With Quote
  #46  
Old 03-31-2017, 10:22 PM
brian_ brian_ is offline
Senior Member
 
Join Date: Feb 2017
Posts: 178
brian_ is on a distinguished road
Default Re: I'm switching my diesel truck to Hybrid

Quote:
Originally Posted by dcb View Post
fiddle brakes would work better than traction control in that situation, possibly better than posi.

all traction control does is reduce torque going to the diff, so that both wheels would have on-ice levels of torque, it is still an open differential.
No, any modern traction-control system doesn't just reduce power when wheel slip is detected - it individually brakes the wheel with inadequate traction (which is what is manually done with "fiddle brakes", if you mean what I think you do by this term.

Not that it matters anyway, as this is a control feature using the brakes, and won't come with the Leaf motor/gearbox, controller, and battery. Adding modern dynamic controls (ABS, traction control, stability control...) to a three decade old German commercial truck seems wildly unrealistic to me.

No traction control (because you're not getting the whole Leaf), and no limited-slip differential (because those are very rare in front drive axles, and not in the Leaf specifically).
Reply With Quote
  #47  
Old 03-31-2017, 10:23 PM
brian_ brian_ is offline
Senior Member
 
Join Date: Feb 2017
Posts: 178
brian_ is on a distinguished road
Default Re: I'm switching my diesel truck to Hybrid

Quote:
Originally Posted by Duncan View Post
Could you just fit the entire Leaf motor and suspension in the front of your wagon?

Throw away all of the VW bits and see if you could make up a carrier to go between the Leaf subframe and some strong points on the VW chassis
I agree with the reasoning; however, the LT is a substantial commercial truck, and even this relatively light variant still has a 2.8 tonne (2800 kg) GVWR. It looks a bit like the 1979-1992 rear-engined T3, but it's not that small. I can't see how the Leaf running gear could have the load capacity or even the track width to work properly.

On this theme, I don't see how the Leaf motor and gearbox can handle a LT 28 with any load in it. It sounds like a recipe for cooked hardware.
Reply With Quote
  #48  
Old 03-31-2017, 10:24 PM
brian_ brian_ is offline
Senior Member
 
Join Date: Feb 2017
Posts: 178
brian_ is on a distinguished road
Default Re: I'm switching my diesel truck to Hybrid

Quote:
Originally Posted by dcb View Post
dunno what the lt prop shaft looks like, but you would modify it so that there is a sprocket coaxial on it, at a spot that is well supported and not moving with the rear end. Then hang the motor longitudinally next to it and chain them together.
Quote:
Originally Posted by CanadaLT28 View Post
I do have a 4WD transfer case available
This makes sense, in that the electric motor could be connected to the transfer case output intended for the shaft to the front axle... but it would not help with the required gear reduction as the chain could.

Quote:
Originally Posted by CanadaLT28 View Post
I've never looked in one but I assumed it was a beveled gear. I believe I read somewhere that is its 2.72:1 but i will have to confirm that. It could help if I could figure out how to still use the leaf gearbox.
Quote:
Originally Posted by CanadaLT28 View Post
I am now told that it has a 1:1 in high speed and 2.7:1 in low speed so it could work, potentially
But that two-speed auxiliary transmission in the transfer case is between the transmission output and the chain to the front output. If it is shifted into low, the engine and transmission run 2.7 times as fast as well... which is not workable for any significant speed. That's what this means:
Quote:
Originally Posted by dcb View Post
the front/rear ratio is still 1:1...
... as well as the following page of discussion.
Reply With Quote
  #49  
Old 04-01-2017, 05:11 AM
CanadaLT28 CanadaLT28 is offline
Junior Member
 
Join Date: Oct 2011
Posts: 28
CanadaLT28 is on a distinguished road
Default Re: I'm switching my diesel truck to Hybrid

Thanks for the comments Brian, I looked long and hard at different options and I talked to Jack at evtv. Although the truck looks big, it is relatively light compared to North American trucks like the F250 etc, and all the info I found seemed to point towards something like the leaf motor. A tesla motor would have been great but there is just too much black box stuff in there plus the very important battery cooling. Jack talks a lot about this and it kind of put me off the tesla for a while. We know know he has cracked the control issues so perhaps it will become an easier proposition in the future.

The fact that the leaf has almost 100% more power than the ICE and that it has to take all the torque associated with an electric helped form my decision. That said, if it fails, it fails.

About the ICE. I had always intended to have a more modern TDI in the truck vs the 70s era existing technology. Even with the load on it, the TDI has 50-80% better fuel economy than the current unit as well as better power and torque specs. As the diesel pump is a proportional pump (I have taken apart and rebuilt a number of them), I feel I can match it's RPM to the Leaf motor to get the best efficiency from it, which theory says, would be running it at about 1600-1800rpm for 80-90kw of output. This would charge the leaf batteries POTENTIALLY faster than I can drain them.

I am OK with being totally wrong in my assessment of this but hope I am not as I already bought the leaf motor, lol.
Reply With Quote
  #50  
Old 04-01-2017, 09:43 PM
brian_ brian_ is offline
Senior Member
 
Join Date: Feb 2017
Posts: 178
brian_ is on a distinguished road
Default Re: I'm switching my diesel truck to Hybrid

When that motor is used to run a Leaf, it will only run at full power for a few seconds (7 sec to get to 60 mph from a standstill) - then the little car is up to highway speed and the power is backed off to a few kilowatts. The truck isn't really heavy, but assuming that you are using it as a truck - not as a four-door sedan with a weird big empty space in the back - it will work hard far longer to get up to speed, then settle down to the much higher sustained power level required to keep those much more heavily loaded tires rolling and to push a barn door through the air.

This is the problem with any car powertrain used for a truck. It can work, but requires attention to durability, largely in cooling. I'll bet that TDi engine gets a much bigger radiator (and perhaps other features such as an oil cooler) when it appears in a Crafter than when it appears in a Golf. The Leaf is Nissan's eGolf.

If you go ahead with the Leaf hardware, I suggest paying attention to cooling, and monitoring temperatures carefully.
Reply With Quote
Reply

Share or Bookmark this

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

 
Support DIY Electric Car
Sponsors

All times are GMT -6. The time now is 08:41 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Ad Management by RedTyger