zamalek

my friend test drove my car last night, the schmuck went to red line & beyond a couple of times while driving, claiming it caught him off guard, specially on dynamic mode, the question is: why didn't the rev. limiter cut off power? also how bad could a couple of trips to 7200 rpm affect the engine?

Proogz

If the engine was warmed up then you will be fine, but if he turned the car on and gunned it down the street, then I would be a little worried to be honest. Never should anyone put that much pressure on a engine when its cold, just not healthy at all...

McGriddle

^^^ x2

DrGP

Rev limiter was designed for exactly the situation you described. Saftey feature to PREVENT over revving and engine damage. It is set lower than what the engine can really safely tollerate. Shouldn't be a problem. But as previously posted, I would not want anyone doing it when the engine was cold. Actually, since you are still in the break in period, it probably did more good than harm.

mellow_sparky

I agree with what everyone here has said. However, you commented your friend went "beyond" redline. The only way that is possible is to downshift to a gear that's too low for the speed you are traveling at (like throwing it into 2nd at 80 MPH). The speed of the car will run the engine up over redline (the rev limiter won't help you).

If that happened, you could be in trouble depending on how far over your friend went (and how many times they did it).

big windy

And that's what we call a "money shift"

McGriddle

That's a great point. Zamalek, is yours a 6MT? If so, mellow's explanation makes sense. Downshifting to too low of a gear will over-rev in any car, and the limiter won't save you. Hopefully, nothing too bad will come of it if it wasn't revving too high or for too long.

zamalek

actually, all 3 7200 rpm run he did were on first gear take off, no down shifting, the engine was about 20 min. running in 80 deg. evening, but i was surprised the rev. limiter didn't cut power @ 7200 rpm, in my 993 it did so just @ red line, also in my clk 55 & bmw 330i, does this mean the red line is set below the danger zone on this car? the car is 6mt by the way.

NABS4

Yes, this means Audi is very comfortable with the 7200 rpm redline and the rev limiter is set a little higher. This is good because if the redline was set at the fuel shut off point, there is a greater chance of bouncing off the limiter which makes the driver (guilty a few times) look like an idiot.

zamalek

that's good to know drgp