polecat702

Just asking, do the S4's have a rev limiter? If so does it need to be reset, or replaced? Probably a stupid question.

Thanks all!
joe

FredR

The S4 and later engines kitted with LH/EZK have rev limiters built into the computers. In the case of the S4 at 6500 rpms the LH stops opening the injectors until the revs drop to something like 6300 rpms and then they start to fire again. I have feeling the EZK does nothing with the spark.

Rob Edwards

There is no mechanical rev limiter, so nothing to replace, per se. There is an rpm-based fuel cutoff value in the brain that you can't do anything about unless you have a sharktuner,

Red Flash

Oh, interesting question. Thanks, Joe!

And how about GTs and GTSs? Anybody have an idea where they cut-off?

FredR

The GT is redlined at something like 6700 or 6800 rpms, the GTS is same as the S4 -as I am aware.

Red Flash

Ah, so the redline and the cut-off are the same?

FredR

On a car with a computer controlled cut off system the concept of a "redline" is somewhat meaningless. other than the rev counter will graphically give the driver an indication of when the system will actuate. In the case of the GT the red lines start at 6600 rpm - there is no line for 6700 rpms.

My first encounter with such a system was in 1989 with my 1986 BMW 535 which in its own right was something of a rocket ship for saloon cars of the day. Just after I acquired it I took my wife out for a spin in it, went to overtake a slow moving car in 2nd, hoofed it and the thing went all squishy- thought I had bent the valve gear! Squinted at the rev counter as this happened and the needle was buried in the red zone. Initially thought I had bent the valve gear but no it ran perfectly ok. Figured the car had a rev limiter- it did thank goodness! I was completely unprepared for the way that motor built revs.

Red Flash

Oh, I'm familiar with the idea, I was just wondering If the rev limiter on the GT and GTS models coincided with the redline.

Sorry for the imprecise wording and making you write so much!