[morrisp]

Hey, just joined the group. I've had an idea for awhile, and I'm looking for some guidance on whether this is completely unrealistic.

I'm going into my senior year as an electrical engineer, I have an A&P, worked as an aircraft mechanic for the last 10 years. Built multiple trucks/cars, and can custom fab most things.

I have been given a soft approval on building a LS/Tesla hybrid as my senior project, I would be joined by 3 other students. Before I submit my full request and begin purchasing components, I'd like to hear feedback on why this would likely be improbable, if that's the case. We would be designing and building a piggyback ECU that would allow switching between gas, electric, both, and taking the signals to integrate both of the motors together. If we somehow have an extreme success, we'd probably go ahead and build some chassis/interior controllers as well.

I will purchase two wrecked vehicles so we have all components, wiring harnesses, or any sending units from both vehicles to reduce nit picking parts online.
The LS4 FWD will be donated from a grand prix or impala, tesla 3/S for the rear motor.

The chassis that everything will be implanted into will be a 55 chevy pickup. I'm in the middle of swapping an entire C5 drivetrain into a 58 GMC 100 to fund the majority of the project. But net cost I am hoping to spend around 25-35k.


Any advice on why this just is not feasible would be greatly appreciated.

 

[remy_martian]

Hybrids are 20 year old technology - as interesting as a steam powered Tesla. Novelty, but useless.

What's the point of an LS when a dual LDU powered car, like @57Chevy is building, will kick an LS/Tesla's ass every which way from Sunday?

Do a dual LDU for your project. Better, a dual Plaid rear drive.

ICE is dead.

 

[morrisp]

Hybrids are 20 year old technology - as interesting as a steam powered Tesla. Novelty, but useless.

What's the point of an LS when a dual LDU powered car, like @57Chevy is building, will kick an LS/Tesla's ass every which way from Sunday?

Do a dual LDU for your project. Better, a dual Plaid rear drive.

ICE is dead.

Because I don't want full electric.

 

[remy_martian]

Electrical engineering school fail

 

[morrisp]

Great job injecting your view because that's the only possible way to ever do anything, anything else is a waste of time... I really hate anything when someone does something that wasn't my idea.
Troll fail

 

[remy_martian]

You have a lot to learn, dear child. It's not "my view".

If you really are in an accredited engineering school, you should have learned the first rule of engineering: "define the problem".

You FAILED to do that.

I interpreted the problem you failed to frame before doing anything: How to get maximum acceleration from a Tesla.

An LS is not an engineering solution. It's a 4 year old's fantasy.

 

[morrisp]

1. Not a child. Again your attempts to belittle people because you have a sad superiority complex does not work.
2. You failed to interpret my 'problem' You are under the assumption, I want max acceleration. Incorrect.
3. My problem, is not how to get the most acceleration out of a tesla drive unit. My problem is integrating a tesla drive unit with a LS engine. If you read my post, you may have been able to deduce that. Unfortunately, your reading comprehension does not seem up to par.
4. Not everything has to solve unknowns, or break new barriers. Sometimes people can do something, purely for the sake of wanting to do it.
5. I really hope you don't speak to people like this in person, or it makes much more sense why you spend your days trolling the forums because people can't stand to be around you.

 

[remy_martian]

Again, what real world problem are you solving by integrating a Tesla drive unit with an LS engine?

Mental masturbation, not problem solving. It's not engineering and you should ask for your money back from the school.

 

[morrisp]

I'm not out to solve a real world problem. Refer to #4.


You might try this IXL Language Arts | Topics for pre-K to 12th grade

 

[brian_]

I get that this is a control challenge, rather than a project to build a useful vehicle. But still, comparison with real-world examples would certainly be helpful; if I were assessing the project I would look in the report (we all know the report is the real product of these projects) for a comparison with existing solutions, and if I didn't find it I would ask. The question would be: "How does this improve on - or at least compare to - the control of the many existing hybrid vehicles of this configuration?" Examples would be any transverse-engine AWD Toyota hybrid (the Highlander Hybrid is the best-known example), but the configuration of hybrid drive to the front wheels (with a transverse engine) and electric-only drive to the rear is quite conventional now.

I'm a little unclear on the one aspect of the design: where does the electrical energy come from? Is the electric drive for the rear wheels powered only from a battery, and the drive for the front wheels only from the engine? Or are you planning a through-the-road hybrid... the least effective hybrid configuration of them all (even though BMW did it in the i8)? If there is no generator connected to the engine, that greatly changes the logic for controlling and coordinating the parts of the powertrain.

 

[morrisp]

I get that this is a control challenge, rather than a project to build a useful vehicle. But still, comparison with real-world examples would certainly be helpful; if I were assessing the project I would look in the report (we all know the report is the real product of these projects) for a comparison with existing solutions, and if I didn't find it I would ask. The question would be: "How does this improve on - or at least compare to - the control of the many existing hybrid vehicles of this configuration?" Examples would be any transverse-engine AWD Toyota hybrid (the Highlander Hybrid is the best-known example), but the configuration of hybrid drive to the front wheels (with a transverse engine) and electric-only drive to the rear is quite conventional now.

I'm a little unclear on the one aspect of the design: where does the electrical energy come from? Is the electric drive for the rear wheels powered only from a battery, and the drive for the front wheels only from the engine? Or are you planning a through-the-road hybrid... the least effective hybrid configuration of them all (even though BMW did it in the i8)? If there is no generator connected to the engine, that greatly changes the logic for controlling and coordinating the parts of the powertrain.

I am open to ideas on which would be more realistic, while attempting to control complexity. The initial idea, which seems simplest, is ICE motor in front controls only the front, rear teslas drive unit controls only the rear, with a battery bank built under the bed. Using the LS to drive a generator and charge the batteries would be great, but I am not familiar enough with the requirements on that yet.

 

[remy_martian]

...and for the same weight as your LS bloatware, you can go full electric and carry additional battery for about 150 more miles of range.

You don't want acceleration. What is the point of this abomination? What does it bring to the party? As Brian said, what does it improve? An MP3 file can make the LS sound if that's why it's in the car.

 

[morrisp]

Basically just to piss you off at this point. That's about the only reason I'll build it.

 

[brian_]

I am open to ideas on which would be more realistic, while attempting to control complexity. The initial idea, which seems simplest, is ICE motor in front controls only the front, rear teslas drive unit controls only the rear, with a battery bank built under the bed. Using the LS to drive a generator and charge the batteries would be great, but I am not familiar enough with the requirements on that yet.

That's understandable, but the effect on vehicle dynamics is significant: the vehicle is front-wheel-drive while under ICE-only power, rear-wheel-drive while under electric-only power, and all-wheel-drive when both power sources are active. The power balance while driving all wheels is determined by... well, we don't know how you would determine that, but strange handling resulting from hybrid system actions is problematic for some hybrid vehicles even with the ability to electrically drive both axles. The worst scenario is when you decide to recharge the battery (to have rear wheel drive power available later for performance) by regeneratively braking the rear while engine-driving the front - this is the "through the road" hybrid configuration.

A lack of any electric motor/generator at the front also means that regenerative braking is only possible at the rear wheels. This isn't a big problem of course - it's true in any RWD EV including any 2WD Tesla - but it does reduce both the efficiency of the vehicle and the amount of braking deceleration which is feasible by just regeneration.

 

[morrisp]

That's understandable, but the effect on vehicle dynamics is significant: the vehicle is front-wheel-drive while under ICE-only power, rear-wheel-drive while under electric-only power, and all-wheel-drive when both power sources are active. The power balance while driving all wheels is determined by... well, we don't know how you would determine that, but strange handling resulting from hybrid system actions is problematic for some hybrid vehicles even with the ability to electrically drive both axles. The worst scenario is when you decide to recharge the battery (to have rear wheel drive power available later for performance) by regeneratively braking the rear while engine-driving the front - this is the "through the road" hybrid configuration.

A lack of any electric motor/generator at the front also means that regenerative braking is only possible at the rear wheels. This isn't a big problem of course - it's true in any RWD EV including any 2WD Tesla - but it does reduce both the efficiency of the vehicle and the amount of braking deceleration which is feasible by just regeneration.

I see what you mean by the through the road system now.
That would be the purpose of our project is to build a module that will control the bias under both engines being active. The initial testing to be able to integrate both motors, we could then move towards integrating a generator to charge the batteries, and finally for regenerative braking. The initial goal of trying to solve all of the problems is highly unlikely for us.

 

[lj516]

Because I don't want full electric.

Hey my man, I'm very much in the same boat as you and love that you are more interested in a good controls problem than just appearing flashy with some sort of basic EV conversion.
I strongly recommend you head over to openinverter.org and evbmw.com there you will find tons of resources for controlling OEM hybrid inverters and transaxles. The hardware is VERY EE Sr Design friendly and ideal for you to get your first experience ordering custom pcbs and populating them(looks great to the judges as well).
The lexus gs450h transmission is exactly what you want for interfacing with an LS and is in fact what I would like to do as well some day since the trans is used in applications of up to 500+hp in the LS600h.

 

[remy_martian]

You just tossed the rear LDU out the window

 

[Electric Land Cruiser]

@morrisp there is definitely something going around the forum lately turning people into assholes. Try not to sweat it. One thing that sets people off around here are Hybrid projects because there are tons of them but precisely 0 that actually function. I'm of the opinion that a DIY hybrid is totally possible but is harder than just making a BEV. You sound like you are dead-set and have the ability to get it done so here is some info.

First check out this project by @Andrewjenkins34, he is doing something similar to what you're talking about: Hybrid Conversion

Secondly, Tesla Tesla Tesla blah blah blah. All modern electric motors are basically the same so you need to choose the one that fits your project, not the one with name recognition. The project above uses a BMW hybrid trans but another option would be a Lexus RWD Hybrid trans. Both have electric motors built in and can be controlled by homebuilt hardware and also can lock up and pass through all the glorious V8 power.

Lastly of all the things in your list of goals ("The initial testing to be able to integrate both motors, we could then move towards integrating a generator to charge the batteries, and finally for regenerative braking"), adding regenerative braking will likely be the easiest.

 

[remy_martian]

Yup...$4 a gallon brings them all crawling out of the woodwork.

Gunna be real fun here when it hits $12/gallon in 5 years.

 

[morrisp]

@morrisp there is definitely something going around the forum lately turning people into assholes. Try not to sweat it. One thing that sets people off around here are Hybrid projects because there are tons of them but precisely 0 that actually function. I'm of the opinion that a DIY hybrid is totally possible but is harder than just making a BEV. You sound like you are dead-set and have the ability to get it done so here is some info.

First check out this project by @Andrewjenkins34, he is doing something similar to what you're talking about: Hybrid Conversion

Secondly, Tesla Tesla Tesla blah blah blah. All modern electric motors are basically the same so you need to choose the one that fits your project, not the one with name recognition. The project above uses a BMW hybrid trans but another option would be a Lexus RWD Hybrid trans. Both have electric motors built in and can be controlled by homebuilt hardware and also can lock up and pass through all the glorious V8 power.

Lastly of all the things in your list of goals ("The initial testing to be able to integrate both motors, we could then move towards integrating a generator to charge the batteries, and finally for regenerative braking"), adding regenerative braking will likely be the easiest.

sounds good, I appreciate the insight and mainly what I was looking for, if this should just be abandoned based on complexity that is prohibitive. I’ll put some more time into researching the best possible solutions before I make the purchases.

Yup...$4 a gallon brings them all crawling out of the woodwork.

Gunna be real fun here when it hits $12/gallon in 5 years.

The great thing about this being a “fun” project, is I don’t have to care about fuel economy. I’m going to head to track this weekend and start asking guys what kind mpg they’re getting 🤦‍♂️