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question 1: the closest you can come to building an entire car engine from scratch is to build it from the basic components. You will need at least the following to be purchased: Finished block, Crankshaft, Pistons, rings, bearings, oil pan, cylinder head, all of the components of the valvetrain, and the entire camshaft drive system. The best way to get experience with all of this is to buy a used engine that needs a thorough rebuild. Completely disassemble and clean the engine (following the directions in the factory shop manual) and rebuild it following all the procedures and specs in the factory shop manual. Before you attempt all of this, yo umust obtain the factory shop manual and study the disassembly and rebuild procedures and decide if you have the skills, tools, and budget for this. Let me stress. The factory shop manual is essential and a great learning tool.
2. To become great at mathematics; good question! I don’t know any shortcuts. Find a good course and do all of the homework and stay ahead in the reading. Also, realize that mathematics is only the basis for the interesting stuff: Algebra, trigonometry and Calculus. Focus on what comes after mathematics.Best of luck to you!
Dave
Yes, this is correct of course. I wish more folks would review their owner’s manual for a schedule of all the required maintenance.
Dave
You do seem to have a lot of ideas for automotive design! The area you are talking about is the general category of car interior and exterior design. Every automotive OEM has big departments devoted to doing this. In order to work in this area I suggest you pursue and education in Design. You might start this by checking out the employment sections of the major auto companies web-sites and look for openings in interior or exterior design. Look at any listings and you will see the education requirements for these type of positions
A lot of folks don’t really understand what “calibrated for 87 Octane” really means. Of course it does mean that the engine can be expected to make its rated power and torque on that gas spec, but it doesn’t mean the engine will not be knock-limited in some normal driving conditions. For one thing, compression ratios are relatively high these days to optimize fuel economy in normal driving. The result of this is that the CR is a little bit too high to not be knock limited at full load. Every manufacturer does this, and they can do a god job because they all have knock detection systems to prevent knock damage and still allow the engine to run close to its knock limit at full load.
Also realize that high ambient temp, low humidity, high barometric pressure, and carbon deposits all hurt the actual knock resistance of an engine in the real world. The normal calibration process doesn’t set the spark advance to run on the knock limit (letting the knock detection system to stay active) under normal high-load conditions. Instead, the spark advance is calibrated to run really close to the knock limit but not to incipient knock. What all of this means regarding Octane is that you might expect using higher than specified Octane to offer a very slight performance and efficiency benefit when you are running at high loads, especially if you are running in hot/dry/ high Baro ambient conditions. Note that some ECU’s have adaptive calibrations that can infer what Octane you have put in your car and adjust the calibration map accordingly.
Interesting question! The basic answer is no, there is no difference in basic engineering quality within a brand line these days. The same technology and materials is used in Corolla as a Camry. The same materials are used in gaskets, seals, castings and stampings. A corolla engine will certainly last as long as even a Lexus engine. The only differences may be found in things like aluminum suspension pieces vs stamped steel in the cheaper car. There are anecdotally just as many Corollas driving around with 300,000 miles as Camry’s and Lexus; same for Honda Civics and Accords and Acuras.
Overall, most of the differences are things you can see, like the interior, performance, ride and handling, amount of sound deadening, etc. There is a lot less profit in entry level cars than upmarket.
In general, nearly every private seller lists a car for at least 10% more than they are willing to sell it for, and every dealership lists a car for much more than that. It is difficult to generalize. You also have to consider that most used car dealers include some form of warranty. The best way to price any car is go to all of the websites that specialize in doing this: Kelly Bluebook, Cars.com, Edmunds.com and Autotrader.com. On these sites you can see the difference between the private sale price and dealer price for different vehicle conditions. Compare them all and make a judgement.
Dave
The simplest performance upgrade is to reduce vehicle weight. Each percent weight reduction feels exactly the same as a percent of power increase at normal driving speeds
1. By 250 K mile longevity, I mean that on a modern engine, maintained by the book, it should be running just fine at 250k miles and not burning more than a quart of oil per 1000 miles, and not leaking fluids. Many modern engines can do more than 300k miles. The other parts of the powertrain, like automatic transmissions do not seem to be as durable. A manual transmission will be very long-life, but the clutch will probably not last much more than 150 k miles. Transmissions need to have fluid changed at least by 100 k miles to get very long life.
You can always put a new engine or transmission in an old car, and you can completely rebuild a suspension; but a car isn’t really failed until the body/chassis is badly corroded2. The toll that time takes on a car is very dependent on whether of not it is garage-kept or not. An outside car will have faded paint, weathered or cracked dashboard and rubber seals/whether=stripping after 10 years. A garage-kept car will not. Constant exposure to the weather is tough on brake systems as well (due to corrosion). Even a garage-kept car will have some deterioration of the rubber parts due to Ozone in the atmosphere. In general, time takes its toll on all of the rubber seals, hoses, and belts throughout the car. A CV joint might be able to last 400 k miles of driving, but once the rubber boot cracks, the grease leaks out and dirt and water get in and the joint fails. Same deal with many of the suspension joints. The final big issue with time is the seasons. Winters with ice and salt are really tough on the body and chassis corrosion. The older the car, the more corrosion on all of the metal and fasteners. Many nuts and bolts can not be undone for service without breaking if they have gone through 10 winters.
The most important thing to understand about high HP cars is that performance is not proportional to engine power, it is proportional to vehicle power / weight ratio. just because a vehicle has high power, doesn’t mean it is fast if it is also heavy.
Dave
On a modern fuel-injected naturally-aspirated engine, there are no easy upgrades that can yield a significant power upgrade. The best that most people can do is install a low-restriction air cleaner system (often called Cold Air Inlet, CAI). You can expect 0-1% peak power improvement with one of these, though they will be noisier than the original, and you will not feel the power improvement. Same with low-restriction exhaust systems.
For power improvements greater than 10% (something you can feel) you need high performance cams or a turbo – kit. These are not for beginners and will require the use of a programmable ECU to tune the engine after the mechanical changes.
For turbocharged engines, all you have to do to get a significant power increase is find a reputable aftermarket ECU or piggy-back ECU, or reprogrammed ECU. These change the engine calibration to allow the turbocharger to reach a higher boost limit, and also reprogram the spark advance. These always require the use of Premium fuel.
Obviously, you can make money or lose it if you are not careful. I think the first thing you need to establish is what your car repair capabilities really are? Know your limits. Can you rebuild an engine? Can yo udo body-work? Are you willing to invest in a good set of tools and diagnostic equipment?
Probably the best profit can be had from buying non-running cars and getting them into reliable running condition, but this requires the most skill, investment and effort.This makes sense. Tires have a “shelf-life” of less than 8 years and have to be replaced even if there is good tread left.
First thing to do is get all of the wheels dynamically balanced. That should solve all of your problems unless one or more of the tires is having structural problems like belt separation, or is out of round.
