Normally the noise of the engine, the feel from the seat of your pants, and (if fitted) the big flashy light are enough to tell you you've reached the rev limit (and therefore should have changed up about a thousand rpm ago). So if you need all that AND a buzzer then might I suggest driving lessons?
I'll make this just for fun, I might make something that beeps when you reach a certain speed instead (for City Driving). I'm a bit busy right now tho.
The 7s and 8s have a shift warning sound becuase unlike piston engines, you don't get vibration or a loss of power at high rpm to know when to shift, also the engine note on the stock exhaust is hard to distinguish at high RPM. 2nd gen and onward Rx-7s have rev limiters, but its very easy to bang into it... hence the sound.
Vibration isn't the cue to change in a reciprocating engine. And you WILL get a power loss at high rpm's to allow you to feel the shift point - Wankels still have a power and torque curve that falls off after a while. So please, don't make stuff up like this.
Should I believe the RX-8 owner or Mr Hairdresser's car?
Anyhow, if this app includes a shift light signal and a speed warning sound, please could the latter not work online in the road cars and MRT - IMO it's cheating to have a warning sound in a car with no pit lane speed limiter.
What the flip has that got anything to do with it? You think I've not spent a couple of hours in an RX-8? You think I don't know anything about Wankels at all? If there was no drop in power then why would that be the rev limit? They'd make the engine capable of revving more and more. Get a dyno trace of an RX-8 and you'll see the power and torque drop off with rpm.
As for vibration, you shouldn't be using that as a shift point in either engine type, as it's got nothing to do with it at all.
So please, don't patronise me until you can hold a technical conversation with engines and performance dynamics with me, rather than the usual spam posts you come up with?
There is a barely perceptible power drop. My point is just that rotaries rev quickly and effortlessly so its easy to bang into the limiter.
Vibration is also a subconcious indicator of shift point for people who aren't paying attention to thier shifts. I'm not saying this beep is a necessity by any means. Mazda put it in there for your average driver... someone who might not be used to the characteristics of a rotary or not expecting it. Its an idiot buzzer. Enthusiats wouldn't need it and they could shift on sound and would be more receptive to a drop in the HP curve.
Sorry for the OT... I just like people to have the facts straight when it comes to my favorite engine
(BTW yes i know, there are PLENTY of drawbacks to a rotary... i'm not saying its all that great of an engine. I just like it cuz its different and neato)
Unloaded they might rev effortlessly and quickly, but whilst actually moving the car in gear they rev as road speed increases, which due to a lack of torque will be slower (for a given car mass and gear ratios etc) than a reciprocating engine. Thus the average idiot actually has more time to change gear! Think how much faster an RX7/8 would be with a reciprocating engine
And there is a noticable power drop after peak power, just like with a reciprocating engine, as the engines increase in revs is more than balanced by the decrease in efficiency of combustion/breathing, oddly enough JUST like a reciprocating engine.
So I still don't see the point of a beep, even for idiots. A nice soft cutting revlimiter is more than enough, and maybe a shift light for racing (but not needed for track days).
I have also made a modified version with a 5 LED revmeter. I currently have it set so that all 5 LEDs come on as a shift light. I have a tendancy to over-engine brake which damages the engine, and this makes it much easier for me to notice when I'm doing it.
The code could be modified to produce a sound rather than drive the LEDs if you know what you're doing with C. Alternatively, you could connect a buzzer up instead of one of the LEDs.
I have done that. However, I had to set the voltage to 12VDC and increase resistors to 550 ohms. Shouldn't be too bad to make. In other words, 330 ohm -> 550 ohm and 9V battery 12V power supply.