Backpressure in your exhaust isn't necessary, but the right amount can give you more power.
Pushrods have their own applications, therefore nothing is wrong with them
Live rear axles are better suited to certain applications then independent rear suspensions, therefore, they are okay.
3000 lbs is light for the modern age of cars, I know, it's sad.
tall gearing on a performance car is fine, again, it all depends on application.
Two door cars =/= sports cars, you're right
You can learn to race from video games See: GT Academy
Most of the time, a 10,000 motorcycle (sounds like a literbike, race replica, whatever price range) will be faster than x. It all depends on how and where you are racing. Motorcycles are inherently bad at turning. The ability to use more downforce because of the stability provided by four wheels instead of two is a major advantage cars have over motorcycles.
There is literally nothing wrong with being a trucker. Getting paid to see the country is pretty cool.
If a convertible was engineered to be a convertible, there is nothing wrong with tracking it. If it is a coupe with the roof chopped off, there is nothing a cage or roll hoop wouldn't remedy to the best of it's ability. It's a different kind of fun tracking with no roof.
Some people who do nothing but play racing vidya and barely have any actual driving experience actually know more than you. They can be really helpful. I consider those autists to be the ALLDATA of car enthusiasm. They know things you may not care to know until you need their help. They have their place to.
There is nothing wrong with getting into cars at an age older than 10.
Some dads are reasonable, some are not. No dad will have the answer for literally every single car related thing in existence that would be impossible.
You can learn anything car related from the internet, you just better hope it's true.
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