I understand that some like to baby their cars, but there is a difference between driving your car hard and neglecting it.

I must admit I did baby it when I first got it, but then I realized, why did I buy a sports car if I was going to drive it like a minivan.

In the end, its all about what you enjoy..

Cheers..

 

Also notice that people in this thread say their rev limiter kicks in at around 5700 or 5900 rpm, that is very strange since mine definitely does not kick in until 6200 rpm..

 

Pushed it to 5,000? You're joking, right? I only shift because I know the rev limiter is about to hit! Where's that... 6,200? 6,500? somewhere around there.

 

My point exactly!

 

lmfao when I test drove the xf for the first time, I pulled out of the dealership lot and bounced off the limiter.. took me less than 3 seconds to hit this milestone

 

Maximum efficiency for acceleration is reached near the 'sweet spot', after that power is falling off. The 'sweet spot' is not to be found at 6,000rpm on this car, just look at the torque curves to be seen on this site.

Maximum acceleration will be achieved when the revs are kept within the power band, that relatively flat zone at the top of the power curve.

Having the car cut out when you hit the rev limiter may impress you and your buddies but on a race track you will be thought to have missed a gear, or even be missing some brains.

 

Who said anything about trying to impress or race anyone? We're talking about driving habits.

The n/a xfire is too slow to race or impress anyone...

 

Just remember which model hit the ground first.. Now don't you have some shirts you need to get ironed before work? And with the list of cars lined up for a turbo charger.. you just might get slapped by an "NA" before too long...

 

Agreed. There seems to be two chains of thought going on here.

The first group have the opinion (shared by my Dad) that an engine should not ever be pushed past 1500 rpm prior to the red line. Some here suggest 2k or more, effectively driving it like a diesel and losing a lot of what the car can achieve.

The second seem to think that whatever the car and whatever the circumstances, higher rpms are better. They take no interest in power bands or torque curves and think the rev limiter is a target, rather than a barrier designed to stop idiots from falling off the cliff.

Me, I love a petrol engine. I love a car that needs and wants to rev. This engine is a little lazy for my tastes and is the first car I've owned that has a single overhead cam shaft and 'not enough valves'. Under very hard acceleration, the perfect point to aim to shift is as the car hits peak power (5700rpm in this car I believe). This type of driving I reserve for overtaking and occasional showing off. Normally I change gear at around 5k when making fast revvy progress.

I have never "hit the limiter" in much the same way that I have never "done a handbrake turn". My last car had a 6900 red line, but I never saw any steeper than ~6100 rpm.

Of course it is a case of each to their own, but I would never buy a car from a person I knew had bounced it off the limiter...

 

Guess we're pretty much on the same page. Miata never saw the rev limiter.. when power dropped off it was time to shift which pretty much felt like it was back into the power band climb..not that she has a big one. But did do the hand brake 180 on a two lane once at about 30 mph.. was kinda fun! But refuse to continually abuse her or any other car I own.

 

That's why you shift right before you hit the rev limiter. It's not just a matter of what's happening when you're in the current gear, but where the R's end up after your shift. You don't want to shift so much before red line that you drop out of the power band when you hit the next gear, right?

 

Hows this for coincedence... running through the Miata forum..

You can safely redline the tach, if you mean going up to the redline. However I wouldn't be doing it with each and every upshift in the case of a Miata or any other car. But why do you have to in the first place? Once you get past peak power and torque, all rpm does is serve as an exceptionally weak testosterone substitute.

 

Does anyone have a link to a stock tq curve diagram for the N/A? Im very interested to see where the inclination really sets in.

 

Oh yes please. I trawled through as many Mercedes brochures as I could find but none had a detailed torque/power breakdown.

 

Gary's (Valky) before tune. You can see the flat area quite well.
Why hit the limiter?

 

Thanks for this. Is the spike at the end an anomaly?

 

I think it's just a spike. LOL
That point is way down so why go there.
Gary after tune.

 

So it looks like peak tq was 198-199ft.lbs at about 2700RPM? And falls off at 4400. If I understand the graph correctly then optimum shift would be about 5400RPMish then right? No point at all to climb anyfurther

 

That will change under real road/load conditions...he's just spinnin' a drum right there....it gives you an idea where the car is...mine, shifts on it's own at 6200 still pulling, not falling off...of course more than likely it is shifting at 5800 and tach momentum is bouncing it forward, but I'm a little too busy to really worry about it at that point...dyno's...lol....

 

With what I hear about SRT acceleration I wouldnt be worried enough to look down and figure out when it shifts either.