So, after being harassed by some Honda vTec cars last night in C Class, I decided to do some research about vTec technology. Turns out Honda was the first to do it, then put a patent on it for 10 years. That patent ran out roughly the year 2000. vTec Technology is simply variable valve timing. Having the ability to change the opening and closing on the valves and different RPM ranges. The Honda vTec engine produces 130bhp from a 1.3Ltr engine. 100hp per Liter is a crazy ratio for a combustion engine. What does this have to do with the Chevrolet 6.2L engine? It also utilizes variable valve timing. The 5.7 Ltr Chevrolet in Forza 6 was not a variable valve engine. The 6.2 Ltr engine will perform very similar in characteristics to a Honda vTec if you gear it correctly. Variable valve timing is a big contributor to performance through the whole power band. When using the 6.2 Ltr keep this in mind when tuning for car. A lot of manufacturers are using variable valve timing technology now. It would be a good idea to google the engine you are considering using, or are using, and see if it has this technology.