I've never actually hit the red, but close to it. I was driving today, getting up to speed on the freeway and I didn't realize it till I looked at the Tachometer and it was right under 6,000, and shifted right before I hit the red. I know every time you do this, you increase the chance of messing up your engine, crankshaft, connecting piston/rods, etc. That's the main reason why I won't leave it at a shop to get mods installed, that's exactly what they do!!! I don't treat my car like a race car, I just like to rev it up once in a while but that's it.