Does stock RS4 have (operational) speed limiter ?

[Jan]

Ok,
some facts:
Stock RS4 is limited to 275 km/h (offically 250).
Quattro GmbH says that unlimited, untuned(!) RS4 runs nearly 295 km/h.

[dog]

So the tuned ones do 310.

[Bushy]

i thought if you applied gear ratios and final drive ratios to max rpm the top speed was 196mph

i will dig out the ratios but for those who know here is the conversion data

mph calc

[Jan]

Dog,
it is not so simple!
It's possible that a tuned car is SLOWER than an unlimited standard car!! [img]images/graemlins/confused.gif[/img]
Why?
Because the question is not: How much bhp has my car?
The question is: How much bhp at what rpm has my car?

Example:
If your car has 450 bhp at 6000 rpm and 370 at, let's say, 6500, and an unlimited standard RS4 will have 380 at 6500, the tuned car has more bhp and LOWER top speed.

So you need to see the complete (up to 7000 rpm) dyno chart of a car, most dyno charts I have seen end at too low rpm.
Maybe some tuners wouldn't sell anything if they would show complete charts.

[dog]

Good point Jan but in the case of the RS4 the top speed is limited by the power but by the redlining. The tuned chip raises the rev where the car cuts out. This is why a tuned car can go faster. Of course a Smart car will not have the oomph to do so but the RS4 is not one of those.

[Jan]

Ok,
let's say that an RS4 (380 bhp, but without a limiter) reaches its top speed at 6500 rpm in 6th gear.
The tuned car is faster, when it has more bhp at 6500 rpm and beyond, than the RS4 (380) has.
If not (it can have 500 bhp at 6000, it doesn't make a difference for top speed), it won't be faster.
Of course then you can modify the gearbox or wheels/tyres for higher speed at lower rpm.

[chrisa1]

[quote]Yes it does and will only go to 170 MPH when de activated

I beg to differ. Mine is Standard and I got just over 180 before limiter came in. (Assuming speedo correct)