Legal definition? This obscure list is from the department of energy, not DOT so I don't know what jurisdiction this even corresponds to. But if you are trying to use a fuel economy list with a Bentley Mulsanne AND a Nissan Sentra on it to equivocate that the model 3 is a mid-size car, your source material is corrupted. And saying that it's the "legal definition" is disingenous.
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performance 20" wheels
- Thread starter Perry
- Start date
Legal definition? This obscure list is from the department of energy, not DOT so I don't know what jurisdiction this even corresponds to. But if you are trying to use a fuel economy list with a Bentley Mulsanne AND a Nissan Sentra on it to equivocate that the model 3 is a mid-size car, your source material is corrupted. And saying that it's the "legal definition" is disingenous.
Knightshade
Well-Known Member
Yes, since that's what it is.
Car makers report mileage by class of vehicle- and some vehicles need to hit certain targets.
That's why classes need specific legal definitions.
So first- the EPA is not the Department of Energy (though they collaborate on that specific website).... Second the DOT does not classify car sizes at all.
The United States government defined size classes in Federal Regulation, Title 40—Protection of Environment, Section 600.315-08 Classes of comparable automobiles.
Therefore the EPA is the authoritative source on the topic.
You can read the federal regulations, which specifically require the EPA to handle this for the US Government, here-
https://www.gpo.gov/fdsys/pkg/CFR-2015-title40-vol30/xml/CFR-2015-title40-vol30-sec600-315-08.xml
No, it's accurate.
I'm sorry you don't like the legal definition of midsized car, but it doesn't magically make it not exist.
Nor have you offered any source for a more accurate one
LMFAO your source material has an Audi S8 as a mid-size car and an A8 as a full-size. Therefore it's a mess and you are using it to make some pedantic reply to someone else who said they wanted a fast compact car.
Knightshade
Well-Known Member
You are, once again, factually incorrect.
It lists the A8 L as full size (large, actually).
Because it's a longer wheelbase car than the S8
Let me, once again, help you out with sources and facts-
2018 Audi A8 | Features and Specs | Car and Driver
a8 Wheelbase- 122.9 inches
2018 Audi S8 | Features and Specs | Car and Driver
S8 wheelbase- 117.9 inches
The A8 wheelbase is 5 inches longer.
That's actually a larger difference than between the Model 3 and the Model S.
So the S8 is classified as a smaller car than the A8L because it is a smaller car
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But the S8 is bigger than mid-sized by their own definition. And a Bentley is huge. Also, wheelbase has nothing to do with the class according to them.
Knightshade
Well-Known Member
Except, it's not.
You can tell because it's on the mid-sized list using their own definitions.
Heck I even linked you to the full text of the federal law defining class sizes. I guess you didn't read it?
Except, it does. Audi uses the longer wheelbase to increase interior room. Which is fundamental to their classifications of size.
You seem to be wrong on basically every thing you've had to say on the topic, and on basic things I keep providing facts and sources demonstrating too.
perhaps take a few minutes to read them more completely, and then consider revisiting your thoughts on the topic.
Knightshade
Well-Known Member
Sorry...it's a long list of cars, once I saw at 3 or 4 quicker than the P model 3 I was safe in making that statement as being correct, but I didn't cross-check every ones 0-60... probably the Dodge Demon? I think it's the only one in the list that runs 2.x 0-60 rather than the low 3s the others do.
That said, I wouldn't be surprised if all the quicker cars in the same class also cost noticeably more....The demon being the cheapest (and also quickest) currently but still running about 85k
(though that may change with the new hellcat redeye, given it is supposed to run 3.4 0-60 and cost around 70k... the downside being dodge makes pretty shitty cars overall and good luck going around corners in the thing...still, they're insanely quick in a straight line!)
Using their definitions there is no way an S8 is a midsized car. Or a bentley for that matter. Based on interior volume, which we both agree is how the EPA classifies cars. Correct?
Vehicle size class - Wikipedia
Knightshade
Well-Known Member
Except they clearly are, because that's how they classify them, using their definitions.
or do you think the EPA is violating federal law and misclassifying cars for...some reason?
Not exactly, no.. the criteria is the interior volume index.
It's defined, in great detail, in the link to the actual federal law defining class sizes....various interior dimensions add up to make the index, in specific ways listed in the law.
It's why a 5" wheel base difference can be enough to move a car from one class to another (S8 vs A8L)
It's also why you might be seeing the 3 classed with some cars you "feel" are "much' larger... because without all that ICE hardware to worry about the car is almost tardis-like in seeming larger on the inside than it should be- as numerous owners have commented on.
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scrapps
Member
ride is too stiff - It's really not. I run 245x35 and 275x30 PS4s.
easy to damage rims when going over slight curbs - that's not true. the PS4s offer the rims better protection than the ties on the stock 18 and 19 wheels.
can't rotate tires since front/back are different sizes - yes you can rotate left and right. The tires and wheels are not directional, so you can swap them.
dgaultiere
Member
This is so obvious if you look around at the lineups of literally every other “luxury” auto manufacturer. And yet, I hear so many people (including the manager of a Tesla store i visited recently) making this same point about the Performance 3 displacing the more expensive S.
Is this because Tesla is attracting so many more buyers who weren’t previously shopping the luxury segment? Or are people just totally oblivious? It’s beyond me...
What is beyond you -- why are people going for the 3 instead of the S?
The showroom I went to kept pushing the S on me while I was looking at the 3. It seamed to me that they really did not want to sell me the 3 but telling me if I am going to spend so much for a performance 3, why not go for the S. So they convinced me to test drive an S 100D.
I was not impressed with the S after having test driven the 3. It felt heavy and lumbering on the corners. Yes it was fast but didn't seem faster than the 3 RWD which felt more nimble around the corners. The S was more money and the 100D would perform worse than my performance 3. I also like the simplicity of the 3 with a minimalist control look and awesome air vent. Both the S and the 3 I thought were sub par on the interior quality. The fit and finish felt cheep on both compared to my Lexus.
Anyway they failed to sell me on the S.
What tires do you recommend on my 18"? I don't see the same Michelin AS4 available on the 18s.
I like performance so I opted to not purchase the performance upgrade. My high school physics teacher taught me that given equal torque a 18” wheel will produce ~11.111% more acceleration than a 20” wheel. That is until the motor torque starts to drop at higher rpm. If someone bought the 20”s in Houston you can help me test the theory in about a month.
I realized while typing tire size is going to throw off my math.
I realized while typing tire size is going to throw off my math.
Knightshade
Well-Known Member
You don't want AS4s, you want PS 4s, which is what comes on the 20s
They make those in everything from 17 to 22
https://www.tirerack.com/tires/tires.jsp?tireMake=Michelin&tireModel=Pilot+Sport+4S
here they are in same size as the OEM tires on the 18s-
https://www.tirerack.com/tires/tire...wall=Blackwall&partnum=345YR8PS4SXL&tab=Sizes
You could possibly go a little wider...245/45s would be 1.5% larger diameter so pretty small difference... 255/40 would be 1.1% smaller diameter so even smaller difference... but not sure if there'd be any clearance issues with the wider tires.... and 255 is as wide as you'd want to consider on 8.5" rims.
dgaultiere
Member
I 100% agree with you about the reasons to get the 3 over an S. I’m in the same boat. But not every buyer feels that way. Many people would prefer the larger, more comfortable, more premium vehicle. The point Daniel in SD was making, and I was reiterating, was that many people will still want a Model S even if the Performance 3 is cheaper and faster. That is obvious to me if you compare a BMW M3 to a 750Li, AMG C63 to S class, etc. The 3 and S are different cars aimed at different buyers. Maybe Tesla needs to refresh the S to make it clear this is a higher end car.
The ratio of the tire radii is not 1.1111, though. The 18” wheels are 235/45 vs. the 20” wheels which are 235/35. So the tire radii (and in turn the torque lever arm at the interface to the ground) are 13.15” vs 13.25”, respectively. Do a few donuts to wear down the 20” tires and they are exactly the same radius. See Tire Size Comparison for details.
I test drove the S and the 3 on the same day and I did not feel that the S was a more premium vehicle. I thought the interior material quality and fit on both was inferior to more established luxury vehicles like my old 1999 Lexus GS 400. I have a feeling the interior on all Tesla models will not hold up as well as my 19 year old Lexus.
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