Learn me: Minimalist shoes?

My car has a tiny footwell, and I have big feet.

I kinda figured the Puma Replicat II shoes I had would fix the problem, but I barely have any idea how many pedals I'm pressing. I might as well be wearing army boots.

In socks, it's great. AFAIK, that's legal on the street - you don't have to wear shoes, but it's not all that convenient.

Worse, SCCA Solo2 Rules 4.3.3 say you must wear shoes that cover the entire foot.

So, I'm looking at minimalist shoes. From the big brands, that's Vibram FiveFingers and Furoshiki, Vivobarefoot, Xero, and some mainstream brands lines, like Merril Vapor Glove, and New Balance Minimus. Honestly though, I'd like to find a cheap, normal looking shoe. Amazon has Whitn, TSLA, Oringiner. There's even a brand called Weweya. 

Thing is, aside from the Five Fingers, I'm having hell finding any info on how thick the soles are. It seems the Five Fingers are between 3mm and 5mm, and I will buy those if I have to.

I want to be able to be legal for Solo2, and to be able to hop out of my car and go into a shop without messing with my shoes for five minutes.

Anyone else using minimalist shoes who can comment on sole thickness and/or driving experience?

I did off road races, in a VW bug (small foot well), in moccasins which I believe are also fire resistant-ish.

What about a pair of proper racing shoes? The ones I had were thin soled and were very little wider than my bare foot

NB minimus and Nike frees work well. Low top Chuck's are the old school answer. 

One of my sons had a set of Puma Speedcats that were much like a low racing shoe, just not fire resistant.

Wal-Mart sells Puma Drift Cats for under $80.

I drove in a couple different kinds of my rock climbing shoes. Kinda expensive but...

https://shophunziker.com/collections/casual-driving-shoes?ref=StoreYa&utm_source=stry&utm_medium=trafb&utm_campaign=storeya2&utm_term=kwd-299310662598
these. Warning they run a little big. I recommend a half size smaller than normal. Thin sole, flexible, look good. Wear well. I can still wear them out on course at AX, although they are a tad uncomfortable to walk in for long periods. I have debated bribing a set of walking shoes with me to ax and then swap to the race shoes when I'm ready in grid. 

i got the lotus version livery. Had them for three years now. 

To keep it simple, I like a good broken-in pair of Adidas Sambas for every day driving feel, but it sounds like you may be looking for something more minimal/racing-focused. In that case, I'd vote for a good pair of actual SFI-certified racing shoes.

I'd go to an outdoors/running store and take a look around and see what they have and what fits well. Getting a thin sole shoe isn't going to help if it is a half size small or big on you, fit will be crucial. I used to wear Merrel Trail Gloves but one thing I found with them is that the sole is very soft/grippy, that sounds good until you are trying to pivot your foot while threshold braking to do a heel-toe downshift and it is planted.

Proper racing shoes are probably the best way to go, they are hot on the feet but the soles are thin, the rubber has the right amount of grip and the rest of the shoe is tight to the foot. They should fit in your foot well just as well as any of the above options and are useful beyond just an autocross or track day where you actually need some SFI safety equipment. I have a pair of low end Sparco's that are nice but there are a bunch of nice entry level options. 

I've done FiveFingers on track.  Actually used them on OneLap in 2011.
Don't do it.  Your toes can get hung up on the pedal... and heel/toeing isn't as "strong" as it is in a "uni-toe" shoe.

I've got some Shoes from Xero (Hana's?  those were the only "shoes they made back in '17.) and Lems.  They're a lot thinner than most, but not "super thin" like you're thinking, and they're ~$80.  Plus, they've got a wide toebox... which is good for me... but might be a waste if you haven't been walking around barefoot/fivefingered for a while.  The Xero Aptos, at $60 is "budgeter", and 5.5mm after pulling the liner... might be a possibility.

I dunno if you can get away with it w.r.t. SCCA's rules.  But, you might check "fitkicks":
https://fitkicks.com/collections/fitkicks-for-men
those are super-thin, almost slippers.

another budget option is pulling the padding out of a pair of vans:

I hate heels on any shoes. If heels were meant to be raised higher than the toes, God would have made feet that way to begin with. So I'm always on the lookout for thin flat-soled shoes, even for everyday use. I have a pair of Astral Loyak shoes and they are very comfy for everyday use and give great feel on pedals too.

If your not looking for fireproof do a Google or Amazon search for "water shoes" these usually have thin soles and in some cases are more like wearing a heavy pair of socks. Some look like running/athletic shoes. Some have drains in the soles which I filled with a tube of silicone to keep from sucking in water, sand, dirt. Most are comfortable slip on types.

I've been wearing these for the last 15 years or so. Saucony Bullet. Great driving shoe. For me they're comfortable to wear all day. I run in them as well. 

I love my Nobull Trainers...they can be had in leather too:
 

Converse All-Stars are my go-to.

I used to also wear RCI driving shoes, which are like All-Stars except not so heavy and clunky.  (But Pete, Converse are not heavy or clunky...)

​​​​Not good for working course, though, as they aren't really meant for walking in and will fall apart rapidly when subjected to that.

I'll cast another vote for Chuck's. 

Just to add another data point, I run in Merrell Vapor Glove shoes. They have a 4 mm stack height (soul + inside liner). They're basically like Vibram Five Fingers, just not as weird looking. Like the Trail Glove, they have a Vibram sole, so you might have the same problem as adam525i did with his Trail Gloves. Trail Gloves have a little bit of padding and a slightly thicker sole than the Vapor Gloves. I wear Trail Gloves as my daily shoe. Both shoes are "zero drop," meaning your heel and ball of your foot are the same height. NB Minimus run small and are very narrow. The heel is 4 mm higher than the front, IIRC.

Over the course of the last 10 years, I've worn: Vibram FiveFingers and Furoshiki, Vivobarefoot, Xero, and Whitin, while my husband has worn similar and Telsa.  He wears a EEEE while I do have a wide foot, but neither of us have long feet.  I can say that the Whitin has a thinner sole than the Xero but it is thicker than my Vivobarefoot.   The Furoshiki do look funky, but are comfy to walk about a mile or so in, and have really thin soles.   I'd say that the Amazon shoes aren't bad and you can't knock the price, if you are just using them for driving.  If you're using them for hiking or running, I'd go for another brand as you can definitely tell a difference. 

Chuck taylors for the win.

Not sure if you'd pass tech, but maybe Nike Aqua Socks or some generic water shoes?

Look at indoor soccer shoes.  I think the aforementioned Adidas Samba is probably the bulkiest of indoor soccer shoes.  There's a variety that fit tight to the foot, are thin-soled, very lightweight, and as a general rule, pretty cheap.  $50-60 usually. 

I've done a lot of driving in Merrell Trail Gloves. Never had a problem with too much traction. :) In fact, I just got back from a test drive wearing a set. 

The nice thing about the Merrells is that they're not overtly weird like the finger shoes are. They can pass for normal. They also last forever because you don't flatten out padding like other shoes. They're also well ventilated which is nice for summer use. 

For thin shoes, the Saucony Bullet

Its a comfy shoe (very similar to the classic Jazz, which Ive loved for decades), much much lower

I actually wore mine today

Stylish. Comfy. Thin.

No experience with them but I've heard that wrestling shoes would work for you