Whatever my current projects are, not meant to be comprehensive.

1. Rinse car with cordless pressure washer.
2. (optional) Use a bunch of rags (microfiber towels) in a bucket with rinseless fluid. Avoid scratching paint with soiled rag.

DIY rinseless wash ingredients:
1 tbsp Baby Shampoo
1/2 cup Distilled Vinegar

Reddit

Roads are not perfectly smooth racing tracks, and even indy or stock-car racing use sidewalls that are 6“ tall. Sidewall flex is desirable for grip.

Indy 500 Racing Tire:

Stock Car Racing Tire:

In the 70s sports cars came with 65 or 70 series tires (like the 240Z, 260Z, and 280Z). People on forums say this is because tire development had yet to evolve to make lower profile tires. I think that's bullshit from people's belief that development is always for the better.

Also see: Tires Are Critical to Effective Suspensions

The truth is that low profile tires are just bling appreciated by an immature clientele. Low profile tires cause a lot of damage so they are also appreciated by suspension and tire shops.

Some people incorrectly assume wider tires give a rougher ride. That's because they continue to use the same pressure on a wider tire that they were using on a stock width tire. The pressure should be less on the wider tire to have the same tire deformation expected by the manufacturers.

Tire Pressure Calculator from tiresize.com

A more comfortable ride can be had by increasing the total volume of a tire.

Increasing the width and keeping the tire height constant, decreases the pressure needed to run the tire. For speed bumps the 2 dimensional vertical deformation is the same for both the wider and narrower tires. At least on speed bumps. On irregular surfaces the wider tire with more volume will be more comfortable.

To be more precise, the narrower tire does have a contact patch that is longitudinally longer, so it may “caterpillar track” over a bump. But the increased volume afforded by the wider tire overshadows what may be a marginal dynamic deformation improvement? I think so.

AWD Subaru differentials need same size wheels to avoid damage and I'm not sure how long they could be driven on a different size spare. Rather than trying to find a spare for my custom oversized tires, I could try using tire repair in emergency situations. It's a nice idea, but it's not convenient to be doing a repair on the side of the road. I like a tire repair kit as a backup to a failed spare wheel. After a long search I found a spare to match the diameter of my wheels.

I watched Project Farm's review of tire sealants and Slime seemed the least nasty looking when he pulled off the tires. Plus it's inexpensive. Multi Seal is more robust but you need a lot and it's more expensive. I've heard good about “Ride On” on Reddit.

For a regular hole on the tread of the tire, I'd much rather use a plug than use sealant after the fact.

However, in my opinion, it would be beneficial to have Slime in the tire as a preventative for future flats. Off-road, by the time you realize you got a flat the rim and tire can be messed up as they roll flat over sharp rocks. Off-road versions of slime can do this for 2 years.

The yellow label slime for highway vehicles is optimized for maintaining tire balance, where the downside is that it should not be used for a lengthy period of time. Slime says: “Once the yellow label emergency sealant in installed, it must be removed within 100 miles or 3 days, or you risk causing tire imbalance.”

I'm going to try using blue label Slime for highway use and see if I have balancing issues. According to one of the reviews on Amazon, using half the recommended amount prevents an unbalance and still has plenty of sealing power. For me 14.5oz / 2 ~ 8oz, so a 32oz bottle for 4 tires.

Click for Reviews

Tires can be repaired with plugs. “Unlike the vulcanization of a patch to a tire, tire plugs rely on the general pressure of the tire hole pushing on the plug to create a compression seal, rather than a chemical seal.” slime.com. Along with the tire pressure, plugs usually come with rubber cement as an adhesive and a lubricant for insertion.

Most any correctly installed plug will work reliably, as tested by Project Farm.

Aside from regular plugs, they make plugs that are self vulcanizing, such as 1 and 2, and some come with separate vulcanizing fluid.

Sidewall repair is difficult, but can be accomplished by vulcanizing rubber and mesh fiber into the sidewall, using both heat and pressure with a tire press machine. See How I do a vulcanized tire sidewall repair, by Misfit Toys on YouTube Amazing skill of Repairing a Hard Impact Sidewall Truck Tire, YouTube

One company even claims the ability to repair sidewall damage without the need for a tire press machine, by using plugs and separate vulcanizing fluid. See Fix Punctures and Sidewall Gashes with Tech's Permacure Repairs, YouTube. Another company: How To Fix Sidewall Punctures Without Replacing Your Tire, GlueTread on YouTube. Although I wouldn't have faith in that kind repair for long term use: I'd want the patch on the inside.

A good compromise for sidewall repair could be a reinforced internal patch, such as sidewall from an old tire. Sanded and buffed to remove the shiny surface, then glued on with vulcanizing fluid and allowed to set under pressure from clamps.

The clamps can be applied onto additional layers of sidewall placed over the patch to distribute pressure more evenly. No need for using pieces of plugs or other strips onto the tire exterior for a simple tear. Cold vulcanizing fluid doesn't need heat as it is a chemical process.

Here's a good example of what I'm talking about, although he places the patch on the outside: sixtyfiveford on YouTube. Good advice about running the chords perpendicular to the tear.

Make sure to mark the position of the tire with the rim.

Use a wooden 4×4 plank to loosen the bead of the tire from the rim, as shown by Smitten in the Mitten on YouTube, then remove the tire with pry bars.

Mounting a car tire on a rim with NO TOOLS in seconds by Spanky’s Hot Rods on YouTube.

Use any vegetable oil as a lubricant for mounting/dismounting. Petroleum based oils harm the rubber. Soapy water is corrosive. See The Tinkering Old-Timer on YouTube.

In case it's too hard with tire levers/irons or pry bars

Y Method for Static Balancing by sixtyfiveford on YouTube. Also describes the difficulty in finding a quality balancer.

Upgrade Design for Bubble Balancer by John Salt on YouTube. Perhaps add a more precise bubble level? See image. Although there isn't room for a larger one.

Alternate

Dynamic Tire Balancing by TarzanRiding on TikTok.

Referring to pre-70's: “Tires were also spin balanced on the car both balancing the tire, wheel and drums of rotors. We also spun heavy duty truck tires on the chassis.” edp9743 on YouTube.

“Useless if the tires are out of round you cannot tell that with a bubble.” danielleclare2938 on YouTube.

Alternate

Full Documentation by derekweaver.com.

• If using a plastic hub-centric ring, it should be removed before mounting on the machine. I'm not sure about an aluminum one?
• Mounting is critical.

How to Use a Shop Dynamic Wheel Balancer by Brunton on YouTube. Good for making sure a tire shop does it right.

Alternate

Maybe the best way is to remove or apply weight using the same strategy as in tire balancing above.

Idea fail

A lead-acid battery, measured without load, should not go under 11.9v. It only takes a dozen or so cycles under this voltage to ruin a battery.

“Batteries can be very long lived if they are charged at a float voltage of 2.20 to 2.30 volts/cell (at 25 degrees C) (13.2V to 13.8V for a 12 V battery).” digikey.com

For 2000s model cars, it's likely ok to charge the battery while still connected to the car, but newer cars may have more complicated electronics? Connect the positive terminal first, then the negative terminal.

Will just starting a car and leaving it on charge the car's battery, or does the car have to actually be driven? reddit.com

You can restore a battery with a welding machine Project Farm

Is it ok if oil is overfill by this much? Reddit. A little is ok, but how much is too much? The dipstick was at the low mark so I added a quart. Now it's quite above the high mark.

My car calls for 5W-30 for cold climates and best gas mileage. However, the owners manual further states: “Recommended grade and viscosity under severe driving conditions. If the vehicle is used in desert areas, in areas with very high temperatures, or is used for heavy-duty applications, use of oil with the following grade and viscosities is recommended.
API classification SM (or SL):
SAE viscosity No.: 30, 40, 10W-50, 20W-40, 20W-50”

Given my engine has 100K miles, I'll be using 20W-50. I'll be waiting a minute after starting the car so the engine warms up before applying load.

If you have a Bluetooth ELM327, and have connectivity issues, one last thing to try is to download different software. That worked for me. For some reason the software made for my ELM327 doesn't connect.

After reading numerous sites and forums, I think it's fine to clear an error code after logging it for future reference. Sometimes there's a glitch and the error doesn't return. For example, random codes can pop-up from having disconnected the battery.

After clearing a code, if the problem persists the error may not return immediately. Some issues require driving a sufficient number of miles (50-70) for the computer to re-diagnose the issue.

For emissions related issues, after clearing the code(s) you will have to wait through a “drive cycle” before the engine light comes on. That can take several weeks, although you can look in your car's owners manual for more specifics.

This Car Scanner app shows which emission tests haven't passed, though it doesn't distinguish between “hasn't passed yet” or “failed”. The engine light will let you know of a fail.

Some super thin ceramic coatings may change surface emissivity but won't much change the surface temperature of the exhaust. I kept seeing really convincing pieces such as this popularhotrodding video. I'm amazed by how deep the marketing rabbit hole goes.

An rx7club.com forum helped guide me away from false marketing.

Easiest Way to Find Exhaust Leaks, Shiny Fast & Loud on YouTube

Dielectric Grease is what you will use for automotive applications: Moto Mythbusters Dielectric VS Conductive Connector Grease, Taco Moto on YouTube.

My engine has a more faint version of the clanking sound in the YouTube video referenced in this forum thread. Also could be a need for valve clearance adjustment, as can be heard in this video. The sound lasts a few minutes on cold startup, and goes away more quickly if I rev the engine.

Performance Engine Rebuild by Project Farm

Total Overhaul at 100K by Project Farm:

“Let's go through a vehicle that has over 300,000 miles on it from top to bottom and front to back to prepare this vehicle for another 100,000 reliable miles! Includes rust repair, front end rebuild, complete tune up, axle hub bearing replacement, fluid changes, new brakes and rotors, front end alignment, headlight bulb replacement, MAF sensor cleaning, tensioner pulley bearing replacement, fan clutch replacement, axle seal replacement, and A/C freon level check.”