In respect to octane I think the article is generally correct keeping in mind there are a number of applications in which using a much higher octane level is required to achieve max performance. We use various percentages of E85 (cause it's less expensive than alternatives in many markets) to obtain very significant hp gains on a number of modded BMW engines. The Demon 170 is a more familiar example where a significantly higher octane level is required for max performance. Both these examples can run w/out issue on 91 but require 100 plus for max performance.
I quote from their article; Let’s start with a classic myth: flipping the lid on an air cleaner. This one comes from the truck world, specifically GM C/K trucks. Back in the day before EFI, cars used huge air cleaners, and GM trucks had some of the biggest around. The idea was to take the top lid off, flip it over and reinstall it to give you a big power boost. This was possible because the lid didn’t sit on the air cleaner element, it went around it, so by flipping it, you open up the air cleaner to pull air from all around. The concept was that by opening up the area around the air cleaner to pull in more air, you would get more air into the engine. This is not wrong as a concept, but actual function does not always follow the concepts. In the end, this does not give you any increase in performance or fuel economy, nothing, zero, zilch. It has been dyno tested and proven so. So why does this myth still exist? It’s fun. The stock air cleaners are not restrictive even though all of the air comes into the air cleaner through a fairly small port. GM’s engineers do make some abysmal goofs, but this is just basic math. The stock air cleaner is capable of flowing more than enough air to serve the engine, moreover, when kept stock (meaning the fender well hose remains attached), the air being sucked into the engine is quite a bit cooler because it is coming from under the front fender. Flipping the lid undoes that, and all the air you pull in is much hotter. So even if you got a slight increase in air flow, you lost whatever you gained with the addition of hotter air. Much as I enjoy destroying people's opinions with facts, I read with my OWN EYES, the magazine article where they did this exact thing. They tried a closed lid, open Moroso filter, and a flipped lid. The stock air cleaner with the flipped lid made more horsepower than either the closed filter housing or the Moroso high-flow open-element air cleaner. Yes, you read that correctly. This was tested on an engine under the hood of a car. Dyno-proven results. Nobody could figure out why it worked, but it worked. Next: "That’s right, kiddos, the thermostat in your engine has nothing to do with how hot your engine runs, nothing at all. If your engine runs at 200 degrees (which is perfectly fine), but you want it to run at 180, then you need to address your radiator and cooling fans. The t-stat temp is not the issue (unless it is stuck, and that’s not the same thing). " Yes, the thermostat DOES control the temperature of your engine. if the coolant needs to be cooler than whatever you are seeing with a 195 degree thermostat, you can use down to a 160 degree thermostat, and it will keep your coolant temperatures down further, without any modifications to your cooling system. As an example, I had a faulty Mishimoto thermostat I put on my vehicle that opened WAY too early, and never allowed the coolant to reach its advertised 210 degree set point, unless I was going up a steep hill, at a slow speed, then the engine would rise to and stay at 210 degrees. The 'moto thermostat was partially opening FAR too early, then fully open by 210. To combat this energy-discarding coldness, I bought and installed a 195 degree thermostat. Voila! Temperature immediately rose to 195 degrees, sometimes wandering a bit higher. It opened fairly suddenly at 195, not like the Mishimoto, which strangely opened from all the way down to sub-freezing on up to 210. Also, fuel mileage vaulted from 13.1mpg to 15mpg. You can see why I wanted a 210 degree thermostat. With Propylene Glycol and no water for coolant, the coolant does not "blanket boil" on top of the combustin chamber roof as it may when water/alcohol coolant is used. Propylene Glycol "nucleate boils" instead, leaving liquid coolant to hug the hottest part of the water jacket and draw heat out, not an insulating blanket of steam to let the combustion chamber roof get detonation-level hot.
