All this "no timing change, no power gain" makes me wonder why the heck the factories make racing motors with wrong timing in the first place
I know full size car factories produce crappy engines due to emission rules and economical limitations, but model engine factories don't have to comply with Californian emission laws...
I run mainly electric touring, nitro as a "side dish" during our short 3 months of bad skiing weather we call summer. I am not a modifier and I've only owned one hand modified engine in my life (which was already couple of years old when I got it), but I'm wondering if I would really benefit from having an "off-the-shelf modified engine"...
I know a fair bit about the engine theory and I have no problems understanding that different conditions require different crank timing, port timing, burn room size/shape, ideally you would have a different engine for every track & every weather. The factory prepared engines are surely a compromise, they must start up and run decently both high up in the mountains at 50C and below sea level at 0C. The question is, when the engine is modified and timing is changed, what are the drawbacks? There must be something that gets worse at the same time, there are no free lunches. Fuel efficiency is probably the first thing to go (especially if the modifier isn't up to the task
), then the engine might become more temperamental (difficult to tune), require certain type of weather conditions to work properly etc... in the end of the day 3% more power does not necessarily mean 3% lower laptimes, it's more complicated than that.