Sun Ra

i've read numerous quotes from porsche engr.s to the effect: "gt3 can safely pull to 9500-10000 rev.s" [sic].

would there be an advantage gained in changing the rev limiter to say 9200, and can it be done thru software changes/easily?

mds

On upshifts, the most effective rev range to use is a function of the adjacent gear ratio spacing and the engine's hp/rpm curve. If you can get more power at a lower rev after a shift than by going to a higher rev in a lower gear then it makes sense to shift. This situations happens when adjacent gear ratios are more the same, such as 5th to 6th. That is why the rev limit is lower in these high gears - it is faster if you shift slightly earlier.

On downshifts, you want some safety margin in case you downshift too early in the braking or, I hope not, downshift into the wrong gear by accident.

Karl S

There's no reason to run the engine at those kind of rpm. Torque and HP both peak much sooner, so you will be on the downward slope of the curves well before 10K. Although the engine might survive a run to 10K, I imagine operating it at those rpm on a regular basis will lead to a premature rebuild. Neither the Cup or GT3 RS are run to those kind of rpm levels.

Karl

johnfm

It depends on the torque curve. If the engien doesn't breath well at 9000rpm+, its no point running it there, as torque & power are dropping off. If you can improve the breathing to extend the torque curve, yes it would be an advantage

If you look at the torque/power curves here:


http://www2.uk.porsche.com/english/gbr/home.htm

you will see that torque drops off alot after 7000 rpm, and power drops off at 7500 rpm.