Episode 2: Fit & Finish
Welcome to episode two of Munro’s Tesla Model Y Performance teardown, where Munro & Associates CEO Sandy Munro offers his expert insight on the vehicle’s fit and finish. His first impression, “the car looked good for an early stage product.”
Click here to join Sandy and his gap gauge as he measures and evaluates the vehicle’s gaps and flushness. During the segment, Sandy offers measurements on key vehicle areas, including:
- Front and rear door top and sills;
- Top of the rear lift gate;
- Bottom of the rear lift gate;
- Lift gate lamps;
- Lift gate roof rail;
- Lift gate to quarter panels; and
- Tail lamps to the body.
Interested in more? Check out episode three for Sandy’s impression of the frunk (trunk in front)and inside trim. For more information about Munro’s Tesla Model Y discovery process visit www.MunroLive.com. This site will offer regular insight from Sandy, interactive data and reports, and livestream from Munro’s headquarters.
An InsideEVs article recently asked “Remember the Tesla Model 3’s Rusty Seats?” Author Gustavo Henrique Ruffo, with the help of Munro & Associate’s Director of Benchmarking Al Steier, was able to provide readers an answer, “apparently, that’s normal.”
According to Ruffo, “whenever we hear about any issue EV consumers may have, we investigate them. That is how we found out Nissan showed a $35,000 bill for a single Leaf battery pack, and PSA had comparable prices for the humble Peugeot iOn. As the biggest EV manufacturer, Tesla tends to present more issues. We dig a little deeper whenever there seems to be a problem, but that helps get facts straight. That is what happened with the Sudden Unintended Acceleration accusation against the company and now with the rusted seats on a Model 3.”
All was quiet … until Munro published its fifth segment of its “Tearing Down Tesla” series where the company analyzed the front seats of the BMW i3, Chevy Bolt EV and Tesla Model 3. InsideEVs reached out and Steier offered some additional insight:
“If you were to look at a number of seats across the various manufacturers, you will find that about 50 percent do not paint the seat supports (bottom and/or back). They will however paint any area that is visible to the customer – i.e. the lower mount points and sometimes the rails if they are not covered with trim. So most have determined that they can live with a little surface rust on non-visible parts. Besides, eliminating the paint is good for the environment.”
In sum, according to Steier, “this is not an issue.” You can check out the entire InsideEVs article for full comments and details: http://bit.ly/3dc0Ows
In December, we kicked off our “Tearing Down Tesla” series of articles that compared notable aspects of leading EVs using our proprietary Design Profit software. We’re concluding the series after eight segments that analyzed topics ranging from OEM assembly time to suspension and from battery cooling systems to HVAC ducting and venting.
We covered a lot of ground in this series and, most importantly, aimed to offer knowledge that’s interesting and valuable to today’s engineers … with data points that support our findings.
In case you missed any of the segments, below the list of topics and where to find the post. Thanks for reading!
Munro & Associates CEO Sandy Munro recently joined Henry Payne, and automotive reporter and expert Lindsay Brooke on the Car Radio with Henry Payne radio show.
Don’t worry if you missed it, we have you covered! You can check out the whole segment here: https://www.detroitnews.com/story/podcasts/car-radio/2020/03/09/car-radio-episode-10-indycar-dixon-munro-cybertruck-gm-evs-race-legend-st-james-autorama/5006663002/
Sandy and the Car Radio team discuss some interesting topics:
- How – and if – the Tesla Cybertruck fits into the truck market (interesting fact, Sandy thinks it doesn’t!);
- Munro’s plans for the Model Y;
- The current – very fluid – state of EV battery technology;
- General Motors EV plans;
- Sandy’s pick for an e-pickup truck; and
A recent Yahoo! op-ed article set out to debunk some of the myths – safety, towing, weight and more – of the Tesla Cybertruck. Notably, the article cited Munro & Associates CEO Sandy Munro on one of the myths regarding the Cybertruck’s weight.
The author shares details to debunk the myth that “the Tesla Cybertruck will be extremely heavy” because it will require a massive battery pack to carry and a body made of 3-mm thick Ultra-Hard 30X Cold-Rolled stainless-steel body parts. According to the article, “it would be in a regular vehicle, not in Tesla’s pickup truck.”
According to the article, Tesla CEO “Elon Musk himself said its weight would be comparable to that of a regular pickup truck of the same size” due to its construction. To underscore this point, the article cites Munro’s comments on the vehicle’s weight and references one of Munro’s technical slides. You can check it out here: https://autos.yahoo.com/op-ed-debunk-tesla-cybertruck-194515763/photo-p-one-came-because-href-194515900.html
Both the Tesla Model 3 and BMW i3 have novel approaches to cooling the motor. This week’s segment compares these approaches. Let’s get to it.
The BMW i3 uses a two-piece motor housing to allow for large coolant channels in the housing walls to cool the housing, which in turn cools the motor and stator laminate stack. The Tesla Model 3 has a coolant to oil heat exchanger on the exterior of the housing and uses the oil to flow through grooves and channels in the stator laminate stack to cool the motor.
The advantage of the BMW i3 design is that it eliminates the need for a heat exchanger, along with the thermal transfer loss between the two fluids. However, the two-part housing requires more processing costs related to casting and machining a second housing component.
The advantage of the Tesla Model 3 design is that it only requires one housing and allows for direct cooling of the stator through contact with the cooling fluid (versus through a housing wall). However, this design requires a heat exchanger assembly and an oil pump to circulate the fluid. These two commodities add significant cost to the motor assembly, but they also have a dual purpose of providing heat to the battery as well as cooling the motor. In this design, the systems pays for some additional functionality.
The general conclusion is that Tesla is increasing their cooling performance of the motor by running oil directly through the laminates, but accommodating this system requires a cost increase for added commodities of a heat exchanger and pump. This drives approximately a $31 cost increase on the Tesla Model 3 versus the BMW i3 design, even though the Tesla was able to use a single piece housing.
Each of the motor housings and companion cooling components were analyzed in Design Profit to understand the full cost of cooling the motor. Specifically, the housing full fabrication process was captured in the software, including the casting and all machining operations.
According to Munro & Associates CEO Sandy Munro, the answer is YES.
This InsideEVs article asks some thoughtful questions about the possibility of Tesla importing the Model 3 to the United States from China.
Would U.S. customers care?
Especially since the build quality is better?
When speaking to Alex Guberman of the YouTube channel E For Electric, Munro said he thinks Tesla should consider importing the vehicle to the United States and other countries from China because Tesla would make more money if they did so.
According to the article, “Munro and Guberman discuss how all cars have a high amount of Chinese-made parts in them, particularly the electronic components. Chinese manufacturing taxes also play a big role in this discussion. China reduces the manufacturing taxes they impose if the vehicle gets exported out of China, lowering the cost per vehicle. Therefore, Chinese-built cars can actually cost less when they’re exported, even after paying to ship them to their eventual destination.”
Be sure to check out the full article for his full insight.
There’s a rather traditional design tradeoff for the IP HVAC ducts in the Tesla Model 3 and the BMW i3. Read on to learn more!
The BMW i3 uses blow-molded ducting, which can reduce material weight and cost by allowing for thinner walls on the duct, but often requires multiple pieces to create the path to route the air. The Tesla Model 3 uses a three-wall injection molded duct, which reduces material weight and cost by eliminating one side of the duct and using the instrument panel substrate for that wall. This design often integrates several pieces into one part and requires more design work and a rather large specialty assembly jig to weld the part to the instrument panel.
Second, the BMW i3 has rather traditional air vents. There are four vent assemblies (two on each side of the driver and passenger) and each vent consists of several small parts assembled to allow for manual control of the air side-to-side and up and down. The Tesla also attempts to reduce cost using a very novel approach to controlling airflow at the vents. Tesla uses a patented air vent design that uses two opposed air streams to control airflow allowing for the need of only two vent assemblies with fewer vent components, as less directional fins are required to focus the air. To further improve the design, they motorized the control (via a touchscreen) to add an additional level of functionality. With this design, they were able to reduce that cost of the components by making it fewer parts, but then put that cost back into the system by adding functionality.
It is interesting to note that Tesla is possibly able to adapt this specialty design with a more complex assembly jig because its vehicle production volume is significantly higher than the BMW i3, which allows those engineering and tooling costs to be distributed across more parts, allowing for bigger development budgets.
In a guest post for Clean Technica, author Ian Richards lists some reasons critics harshly judge Tesla CEO Elon Musk, including his “run-ins with the SEC, intemperate tweets, and a catalogue of missed deadlines show that he does not have the character or the competence to run a major public company.”
However, according to Richards, there is a problem with these judgments. While “all the major automakers are experiencing declining sales and laying off workers. Tesla just recorded a blowout quarter, and is growing unit sales faster than any automaker in history.”
The article discusses some of the reasons for Tesla’s success. Many are the result of Musk’s innovative thinking and leadership that inspires groundbreaking products and technologies, including one example where he quotes Munro & Associates CEO Sandy Munro:
“The Superbottle is a great example of how the normal automotive companies don’t work together, and Tesla does. That Superbottle crosses many lines that you can’t cross here (in Detroit). If I’m in charge of engine cooling or battery cooling, I don’t want anything to do with cooling the cabin. And yet, we’ve got the motor cooling, the battery cooling, and electronics, all going through one little bottle that’s got some clever little ball valves that open and close to make sure that everything’s getting heated or everything’s being cooled to where it needs to be. We all thought that was the best thing in the whole damn car.”
For more insight on why Richards calls Musk “the smartest CEO in the auto industry,” check out the full version here: https://cleantechnica.com/2020/02/19/elons-secret-sauce/.
Did you know that the Tesla Model 3 does not have a parking pawl and actuator in its gearbox?
The Tesla Model 3 is unique, as it doesn’t have a parking pawl and actuator in its gearbox like most other electric vehicles, such as the BMW i3. This is potentially made possible by relying more on the EPB (electric park brake) units on the rear calipers in the brake system.
For reference, the BMW i3 also has EPB units on its rear calipers, along with the traditional park brake pawl in the gearbox.
Data: The BMW i3 spends approximately $25 on parking pawl components and assembly, more than half of which is associated to the actuator for the parking pawl. These are costs that the Tesla design avoids incurring.
Methodology: Using Design Profit’s comparison tools, Munro was able to identify cost and component differences between the two designs.