Desigining something of your own is a great project, designing the best solution for achieving "crazy performance and reliability" in a model (RC) car possibly would not be by using a V8 engine! - I think you will find that a fairly high performance single cylinder two stroke engine and properly designed exhaust chamber would beat it hands down, both in the power to weight ratio, the outright power and the cost, (unless cost is no object).
Then, in the reliability stakes..... what if the engine seizes and/or breaks one of those rods you so lovingly fashioned, or bends the beautiful big long crankshaft you spent a month making? ... in the case of the two stroke, probably a reasonably simple repair and back in business!
Point is, what do you want? - to be a draughtsman/designer and let your mind roam free? to have fantastic performance - with a model V8??, To have a very reliable and competitive model car- with a model V8? - to be a competent machinist to make all this come about?
That's what I meant when I said earlier, "one step at a time" and I'll add a bit more "everything starts with a dream, but for the dream to come true it needs to be tempered by reality".
Still, no harm in dreaming - I always did, but I have also faced all the realities (and disappointments )through my forty something years in engineering, - don't lose the dreams, but pace yourself and remember, learn only one discipline at a time - but keeping the others in sight - good luck and do well.