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L83 Squarebody 48V Hybrid Project

1049 Views 2 Replies 3 Participants Last post by  mikealdridge2222
Hello there,

I am a rural Canadian hillbilly(so think -30, snowing, mud caked tank trap life or death conditions that would make 90% of pickup owners chicken out).

I am mapping out my first hybrid build - with 10 years of professional experience in vehicle maintenance. I find the lack of retail 48V kits frustrating, given its proven technology among OEM's, but I'm considering reaching out to ST or SEG myself to buy direct from them and build my own kit.

Here's my deal: I have a late model 5.3 V8 4x4 GMC 1500 I can cannibalize, I'm hunting for a clean 81-87 GMC or Chevy K20 or K30 long box, regular cab. My intention, one way or the other, is to mount the flex fuel V8 and 6L80 transmission into the squarebody (that's the easy part). Money is a factor, time is not. I have a bicycle and my wife's car until the build is complete.

I had ideas about making it a proper series hybrid with an adapted Tesla S powertrain - but that is outside my budget, because I'd have to convert to a smaller ICE I don't own or know the history of. I also considered a parallel system where a 100kw-ish electric drive is mounted to the front wheels only, allowing a conventional rear drive and some clever programming - but the fit becomes wildly impractical unless you do some kind of monster lift kit, and build a custom load-bearing live axle to house the drive unit.

So, the most practical way, by far, to "green up" the build would be a 48V mild hybrid system. Here's what I want:
  • Regenerative braking
  • Garret or Torque Amp electric turbo, mapped to tuner, different settings
  • Electrification of accessories (as far as practical)
  • High output belt driven starter-generator (surplus under maximum load, idle conditions, as long as the idle isn't unreasonably high, modes may be programmable depending on battery charge state)
  • Battery and charge controller(s) obviously
  • Respectable and combined 12 and 48V battery capacity - for "engine off" use
  • 120 VAC inverter with cab and bed outlets for power tools, etc.
  • Custom and easily accessible auxiliary fuse or CB box for hybrid systems
  • Master hybrid shutoff - I'd like to be able to have enough redundancy that the 5.3 ICE drive system doesn't die in the event of hybrid system faults, and the starter generator reverts to alternator function - if possible
  • High weather durability - rain, sleet, snow, and deep trenches full of mud
  • High reliability - overbuild and derate will be the keywords.

Here's what I don't want (for a plethora of reliability and simplicity reasons):
  • Active start/stop functionality
  • Coasting and other driving-condition based modes
  • GM's e-assist, as a package, won't work, because it lacks some functions, and has others that are counter to my philosophy. For example, GM's V4 economy mode causes oil starvation to the lifters, so it is disabled by any and all tuners - and rightly so.

So yeah, see how things go, and feel free to chime in! Or if I end up doing a parallel electric front end after all. We'll see if Magna's e-beam amounts to anything as a possible solution.
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The DoD is where most of the fuel economy comes from....I think you'd get better mileage activating DoD than with your proposed hybrid setup.

But, yeah, it sucks for reliability...mine died at 200 klicks. It got 25mpg, which is not bad for a 5300lb SUV.
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