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Hello all I am an retired Powertrain Development Engineer. I have been working on a new car design all aluminum chassis mid engine high-end sports car. I want to make the Powertrain EV not gas. I want to put reliable 700hp equivalent in EV. I am disabled from Iraq war I want to use an Auto Transaxle but I was told it is advised to use manual. Can I put a dual motors inline and double the power of the warP11 motors or how can I achieve this? Can I use a paddle shifted Auto Transaxle or do I need to stick to manual? Lastly batteries I love the Optima gel technology is this an economic way to go and how much range can I expect with 10 yellow top deep cycle? I know I am asking a lot and I want to say thank you all for your time and assistance.
 

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I'm having a lot of difficulty reconciling the term "supercar" with the assumption that long-obsolete motor and battery technologies would be used, with very low battery capacity. What are your performance targets?
 

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The viability of an automatic transmission depends on the type of transmission (traditional planetary with hydraulically actuated clutches and torque converter? dual-clutch?) and details of the controls. I think the specific motor should be better understood before worrying about the transmission, because a multi-speed transmission might not even be needed.
 

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Hi medic

What you want is doable - but not the way you are proposing

First - batteries - Lead is Dead - it's simply impossible to get "OK" performance out of lead - never mind supercar - and about 20 miles range is about all you will get - with a two year battery life

Second Motors
Warp 11's are just forklift motors - and you can get decent performance but they are NOT very sophisticated

A much better idea would be to use a Tesla power unit - complete motor and reduction gearbox - a little less than your 700hp unless you use one at each end

700 hp from an electric motor is effectively a lot MORE than 700 hp from a petrol engine

The Tesla unit would also remove the problems about gearboxes - it's a single speed reduction gearbox

The BIG problem with EV's is somewhere to put the battery

If I was doing what you are I would start by getting a crashed Tesla - and I would be working on effectively putting the Tesla go bits into a smaller lighter body/chassis

The Tesla will have supercar performance - with half of that weight.....
 

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Duncan's suggestion of using a drive unit from a production EV (such as a Tesla) is an example of an alternative motor choice which brings a transmission with it; this would eliminate any transmission work (but brings other issues). That's why I suggest first understanding performance needs, then what motors might be suitable, and only then what that means for the transmission.

An example of a project in what might be the format being considered, using a Tesla drive unit, and described as a "supercar", see snowdog's Electric Supercar.
 

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Discussion Starter #6
I am trying to build my own driveline this is a production intent vehicle in line of Lamborghini F488 cars for 200mph plus. I have built a lot of cars my last was a 204mph Cadillac CTSV. I am retired and disabled this is why I asked about the automatic Transaxle I have a lot of work and research to do thank you all for the insite
 

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I am trying to build my own driveline this is a production intent vehicle in line of Lamborghini F488 cars for 200mph plus.
Cars such as the Ferrari 488 and various Lamborghini models are generally used on the street to impress people, and on race tracks for recreational lapping. The street mode is relatively easy (although I don't know how impressed people are by the whine of an EV), but the sustained high-power operation of track lapping is a huge challenge for an EV. I think that it is important to consider how much power is needed and for how long, to understand both the battery requirements and the motor requirements. For instance, a couple of over-volted air-cooled brushed series DC motors can produce a lot of power for the length of a dragstrip and even briefly reach 200 mph, but wouldn't likely make a single lap of a race track without overheating.

As for production intent... this sort of car makes a great challenging project. Many companies have gone bankrupt trying to build high-performance sports cars with conventional technology; doing it with obsolete EV technology while competing against the largest automotive companies in the world seems doomed to immediate failure. Perhaps there is an automotive market segment which isn't already over-populated with capable competitors?
 

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Thank you all a lot of people have told me things are not worth it or can't be done. But I am that person who does not give up. My creations are driving everyday and hold patents but I strove on a challenge I will update as I progress, again thank you all
 

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Hello all I am an retired Powertrain Development Engineer. I have been working on a new car design all aluminum chassis mid engine high-end sports car. I want to make the Powertrain EV not gas. I want to put reliable 700hp equivalent in EV. I am disabled from Iraq war I want to use an Auto Transaxle but I was told it is advised to use manual. Can I put a dual motors inline and double the power of the warP11 motors or how can I achieve this? Can I use a paddle shifted Auto Transaxle or do I need to stick to manual?
If you're a retired powertrain engineer (many people use the term "engineer" very loosely, so without stating a background portfolio of accomplishments, the unqualified statement has kinda been made worthless by others), you should know the answer on the transaxle. In any case, is the paddle shift for looks/ergonomics, or are you after millisecond shifting? That will determine if you use a dual clutch or a regular slushbox from an ICE donor. Dual clutches are starting to emerge in "regular" production cars, but they typically are in high gear-count units (read that as "heavy") like an 8-speed. You're being told to use a manual transmission by people who probably don't have the knowledge/skills/equipment/time/money to make the hydraulic circuit happy.

You also don't fully state your available funds for the project or your specific disabilities (which are none of our business, but will determine what YOU can actually do in the build - there's a lot of heavy lifting and dexterity needed in a build - doing it without arms, or from a wheelchair won't be easy...merely finishing even some of the individual pieces of a complex project is formidable if it's a mental disability).

Dual motors are possible,

https://www.evwest.com/catalog/index.php?cPath=8&osCsid=8pgknlbiio3jkopdbn0qqvlrl0

but are going to be heavy AF and you likely will need to fab a waterjacket (see Netherlands (I think it was) boat implentation elsewhere on the forum) for sustained performance on some. Your weight distribution and polar inertia might suck if you're not careful...mid-engine is not a panacea. If you're an engineer, you should know how to do all this, the math, and the execution.

As others have said, your choice of energy storage is quite questionable, but despite the "ick" factor of lead, as compared to present-day technology, lead batteries STILL have *some* advantages (this is gunna trigger the lithium fanboys, but an engineer won't be) - for example, with a deep cycle, you won't brick it like you will discharging a lithium cell, you can't charge a lithium in cold weather without heating the pack, etc.

Your choices are those that would have been made 20 years ago (you also don't say WHEN you retired and possibly unplugged yourself from technology awareness). Your use of an aluminum chassis works for any platform, but a lighter overall car cascades things like amount of storage, torque needed, gearbox heft, etc.

All depends on constraints you never gave, but probably know. Every choice you've made so far will make a fatso car that will suck relative to others if it's on a track or strip, rendering the pain in the butt fabrication of aluminum a waste of time, IMO. Fact, not denigration.

You can do anything as long as you have time, money, resources, knowledge and skills. The latter two can be acquired, and unlike the popular saying goes, money CAN buy everything (for an EV build), including hands if you don't have any.
 

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I am an engineer and I will say that you don't "Brick" a lithium pack that was only an issue with the early Tesla Roadsters and was not so much a damaged battery as a computer system that crashed -
you can damage some of the cells
But guess what happens if you over discharge a Lead Acid battery!
 

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The reference to "paddle shift" has caused some confusion. Any automatic transmission can be shifted by paddles instead of a traditional lever, so it's not clear what type of transmission was intended.

Dual-clutch transmissions are far from "starting to emerge", but have also been recognized as having little if any advantage, as planetary automatics can shift just as quickly and operate just as efficiently. The planetary automatics sold alongside those 8+ speed dual-clutches are also 8+ speeds - up to 10 speeds in regular production units (from Ford and GM) - and it's rare to find less than 7 speeds in anything introduced in the last decade.

The latest generation of Corvette (C8) will use a dual-clutch, only because that's the only transmission type that an outside supplier would make for GM in such low production volume and limited other applications. It's not chosen for performance.

If an auto manufacturer were looking for the optimal multi-speed transmission technology for a production EV, they would probably end up building a dog-ring type automated parallel-gear transmission with no clutch... or more likely they would buy that from one of the existing suppliers. What a person would do with zero production volume and no facilities to build a transmission is not so obvious, but certainly adapting any recent transmission designed for use with an engine will result in an excessively heavy, bulky, and inefficient system.

One puzzle in this choice is that with obsolete motor and battery technology, the use of current transmission technology seems unlikely... so why even discuss dual-clutch transmissions?
 

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Hello all I am an retired Powertrain Development Engineer. I have been working on a new car design all aluminum chassis mid engine high-end sports car. I want to make the Powertrain EV not gas. I want to put reliable 700hp equivalent in EV. I am disabled from Iraq war I want to use an Auto Transaxle but I was told it is advised to use manual. Can I put a dual motors inline and double the power of the warP11 motors or how can I achieve this? Can I use a paddle shifted Auto Transaxle or do I need to stick to manual? Lastly batteries I love the Optima gel technology is this an economic way to go and how much range can I expect with 10 yellow top deep cycle? I know I am asking a lot and I want to say thank you all for your time and assistance.
If you google White Zombie you will see one of the most successful dual motor dragsters with a 0 to 60 in 2 seconds and the capability to pop wheelies. It was on a Netflix Fastest Car episode and crashed after years of not being raced. If you do what you are considering in your chassis you will not have traction control unless you integrate some of the Tesla's systems which I have no idea to do. I do think a Tesla infusion has advantages over the dual motor/Zilla builds. Lithium should be your preferred battery technology as lead has short life and not really that cost effective.
 

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If you google White Zombie you will see one of the most successful dual motor dragsters with a 0 to 60 in 2 seconds and the capability to pop wheelies.
I can only guess that cars like White Zombie inspired this project, but running for the few seconds of a drag race is very different from track or even street driving any sports car, let alone a "supercar".

If you do what you are considering in your chassis you will not have traction control unless you integrate some of the Tesla's systems which I have no idea to do. I do think a Tesla infusion has advantages over the dual motor/Zilla builds.
There is nothing special about Tesla traction control - it works the same way as the most basic current economy car: reduce power if both wheels driven by a motor are spinning, and apply brakes individually if only one wheel on an axle is spinning. Even using a complete Tesla drive unit with controller won't give you effective traction control unless (unlike any Tesla-based conversion ever built) you also include the complete Tesla brake system... and even then, you have fundamentally no different traction control than using the corresponding components from any other EV.

But traction control is essential for anything like "supercar" performance.
 

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Brian -- sounds like you, surprisingly, don't know about the Quaife retrofit for Teslas that gets you a "posi", albeit for a bit over 2 grand. Jack Ricard sells it for his usual arm and a leg. If it was half that price, they'd be selling a metric poop-tonne of them, IMO.
 

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Brian -- sounds like you, surprisingly, don't know about the Quaife retrofit for Teslas that gets you a "posi"...
I am aware of it, and have discussed it in other threads; it's just not relevant here. The need to fit an aftermarket diff to get limited slip in a Tesla drive unit illustrates that a stock Tesla has open diffs and depends on a brake-based system for traction control.

Yes, Medic1236 could use a Tesla drive unit in this car (like the other current "supercar" project in the forum), and add the Quaife for slip limiting (but not traction control), but that's not what he is planning, and retrofits for Teslas won't help him with traction control in his WarP-motored car.

Again, there is nothing special (or even up to average for the class of car) about Tesla traction control.
 

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As far as traction control is concerned all electric cars have a major advantage over dino burners

The aim is to stay as close to the optimum grip point as possible
Dino burners require a relatively long time - at least a quarter of an engine revolution to change engine torque

Electric motors need one controller cycle - normally over 20 kHz

That faster response time is very useful in getting right close to the maximum grip point and is part of why Teslas are so fast on the drag strip despite using fairly "normal" tyres
 

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As far as traction control is concerned all electric cars have a major advantage over dino burners

The aim is to stay as close to the optimum grip point as possible
Dino burners require a relatively long time - at least a quarter of an engine revolution to change engine torque

Electric motors need one controller cycle - normally over 20 kHz

That faster response time is very useful in getting right close to the maximum grip point and is part of why Teslas are so fast on the drag strip despite using fairly "normal" tyres
LOL :D
At 6000 rpm, a quarter of an engine revolution (one cylinder firing in a four-stoke 8-cylinder) is 2.5 milliseconds. Yes, one EV motor controller cycle is faster than that, but both are far quicker than required, given the mechanical system between the engine or motor and the tires and the responsiveness of the tires themselves. And Tesla doesn't use motor power control until both tires on an axle spin: the response to a single tire slipping is by the brakes. Yes, the same brake-based traction control used by every other car that is missing an actively controlled differential.

Tesla models used in drags just have a lot of power - for the few seconds required for the run - which is available without interruptions for shifting, and AWD.
 

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Brian
Have you ever been to a drag strip?

The first two seconds or less are critical - and engine revs are not "6000 rpm" during that critical part
 

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Hello all I am an retired Powertrain Development Engineer. I have been working on a new car design all aluminum chassis mid engine high-end sports car. I want to make the Powertrain EV not gas. I want to put reliable 700hp equivalent in EV. I am disabled from Iraq war I want to use an Auto Transaxle but I was told it is advised to use manual. Can I put a dual motors inline and double the power of the warP11 motors or how can I achieve this? Can I use a paddle shifted Auto Transaxle or do I need to stick to manual? Lastly batteries I love the Optima gel technology is this an economic way to go and how much range can I expect with 10 yellow top deep cycle? I know I am asking a lot and I want to say thank you all for your time and assistance.
So getting back to the OP, the real question we are asking you is we need more info. First off I would like to thank you for your service, I'm a disabled vet as well and wish you the best of luck with your project. Even if it never gets finished the project alone can be great therapy. I'm also about to graduate university for Aerospace Engineering and Powertrain Development Engineer is one of the positions I'm looking at. #CountingDownTheDays!
Now back to some questions.

If money is no object, or very little of one, due to the fact you are trying for 488 territory, you need to look at high end motors. Teslas are great and pretty darn efficient, especially the Reluctance motors on the Model 3, but are also made for volume production so they are cheaper and heavier than they could be. You probably want to look at more motorsport level motors to get the weight down. I suggest axial flux motors, aka pancake motors. They are extreme power dense and highly efficient, >95%. Companies like YASA, Phi Power, and Integral Powertrain. YASAs are used in the Koenigsegg Regera, a couple of electric planes, and also in the electric land speed car that my university is building right now (shooting for >250 mph). Phi motors are used by some teams in FormulaE. And Integral motors are used by the VW ID.R that has broken a ton of records like Pikes Peak, Nurburgring, and Goodwood just to name a few. These kinds of motors will give you the power you want in a very small package. Some companies sell a motor controller with it, or you have to get a separate one. I personally like RMS since they are used in motorsports like electric rally cars and on the Koenigsegg and used by YASA to develop their motors. Very high quality motor controllers and very nice people too. You will have to develop your own cooling circuit but that shouldn't be too hard. Basic heat transfer equations.

Also, one of the main good things about those motors is you can direct drive them to the wheels, they don't need reduction gears or gearboxes. A reduction gearbox might be better performance in acceleration depending on which motor, but you can design and build that for less money than a used manual transmission which is very heavy.

As for batteries that can be a difficult one (trigger lots of fighting... I mean debates lol). The biggest questions you need to ask yourself is how much range do I want and how much work do I want to put in it? Lead acid is reliable, predictable, and cheap, but very heavy so lowers the performance nature, and doesn't have a good range. Lithium would be your better bet if you want a usable range but there are a lot of chemistries. This is where the other question comes in. How much work do you want to put into JUST the battery pack. If you don't mind the work, then hell yeah do your own custom pack with your own BMS, cooling circuits, safe guards, failure mitigation, maintainability, etc. But if you don't want to do the work, then Model 3 battery modules are some of the best on the market right now. They are engineered VERY well and their BMS boards are very well done. It is hard to beat their engineering. Only issue is you have to deal with their voltage and size/shape of their battery modules. So you will have to design around that.

Sorry if it got long winded there, but in short you really need to ask yourself about how you are going to use this car: range, costs, charging, maintainability, etc. Have fun with the project!
 

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If money is no object, or very little of one, due to the fact you are trying for 488 territory, you need to look at high end motors. Teslas are great and pretty darn efficient, especially the Reluctance motors on the Model 3, but are also made for volume production so they are cheaper and heavier than they could be. You probably want to look at more motorsport level motors to get the weight down. I suggest axial flux motors, aka pancake motors. They are extreme power dense and highly efficient, >95%. Companies like YASA, Phi Power, and Integral Powertrain. YASAs are used in the Koenigsegg Regera, a couple of electric planes, and also in the electric land speed car that my university is building right now (shooting for >250 mph). Phi motors are used by some teams in FormulaE. And Integral motors are used by the VW ID.R that has broken a ton of records like Pikes Peak, Nurburgring, and Goodwood just to name a few. These kinds of motors will give you the power you want in a very small package. Some companies sell a motor controller with it, or you have to get a separate one. I personally like RMS since they are used in motorsports like electric rally cars and on the Koenigsegg and used by YASA to develop their motors. Very high quality motor controllers and very nice people too. You will have to develop your own cooling circuit but that shouldn't be too hard. Basic heat transfer equations.
It is a huge jump to go from brushed DC motors to the most exotic thing that can be purchased, and Medic1236 has stated his clear intention to use a brushed DC motor, along with lead-acid batteries. If he were to adjust these starting design assumptions, it's not at all clear that there would be enough benefit in the most expensive motors to justify giving up the integrated reduction gearbox that comes with a production EV motor.

It would help to understand the requirements better, which is why I have been asking about them. If "supercar" means an occasional stoplight testosterone display, or Friday night drag strip run, then even the clearly marginal stock Tesla cooling will do, and the power-to-weight ratio is fine. All day hammering out laps at Laguna Seca, on the other hand, will need better than production EV handling of heat, and actually reaching what I would consider supercar performance may call for a slightly lighter motor.

Also, one of the main good things about those motors is you can direct drive them to the wheels, they don't need reduction gears or gearboxes.
I don't think going without reduction gearing is a realistic expectation. Yes, you can hook up some YASA P750 motors to halfshafts, but you would be using a small fraction of the operating speed range of the motors. Buying four times as much motor as you need to avoid a set of gearing doesn't usually make economic sense. None of the exotic and competition examples given is an EV operating its motors without reduction gearing, as far as I know; for instance, the Regera is a hybrid with most of the power coming from the engine with no electric involvement, and conventional Formula E cars don't use direct motor to axle connections because they're not allowed to use separate motors per wheel in their rules.

There was a set of YASA P750 motors and controllers sold in the classifieds here, and they are now part of a conversion project with a direct motor-to-axle configuration... but of a Mini, not anything like a "supercar". I hope it works out well, but it's a lot of motor for the performance, which probably makes sense only when one gets an exceptional deal on surplus hardware from someone else's expensive project.

A reduction gearbox might be better performance in acceleration depending on which motor, but you can design and build that for less money than a used manual transmission which is very heavy.
Certainly a conventional transmission adapted to an electric motor is not an optimal configuration. If you are buying multiple motors for several thousand dollars each, and driving each of them with a controller that costs several thousand dollars, salvaging an inappropriate transmission doesn't make a lot of sense to me. On the other hand, designing and building a gearbox is beyond most people (including those building conversion projects), so using an available gearbox (such as a single-ratio box intended for EVs, such as salvaged from a production EV which also provides the motor) is appealing.
 
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