Have you ever noticed the redline on your tachometer? Well, first off, do we know what the tachometer is? That’s the gauge next to your speedometer calculating your RPMs. Your tachometer will have numbers ranging from 0RPM- around 8RPM. The redline sits right around 7-8RPMs. What does it tell us, is it safe to hit the redline, or is it just an effect to make your car look cool?
The redline on your tachometer is telling you something. You are going over the max RPM limit your car can handle, and if you keep it up, your engine will explode. Definitely not a safe line!
While hitting the redline is more frequent in manual vehicles, you need to be aware of your RPMs and what they are telling you. So let’s dig in!
Redline Safe Line? Think Again!
First, I want to define some terms we will use that you might not understand.
Tachometer: The gauge that measures the working speed of your engine. It sits next to your speedometer and shows 0-8 RPMs.
MPH: Your miles per hour / how fast you are going.
RPM: Your revolutions per minute, measuring your rotational speed.
Redline In Automatic Vehicles-
If you are driving an automatic car, you will hear your car rev up then back down, catching the next gear, and revving (aka accelerating) more depending on how fast you are going. Automatic cars should really never hit the redline unless you are parked in neutral. The whole point of driving an automatic car is automatically shifting between your minimum and maximum RPMs.
To experiment, sit in your car and put it in neutral. Slightly step on your gas pedal and listen to your vehicle. You will hear it revving more and more and if you watch your tachometer, the spindle will go from 0 RPMs and keep rising. The harder you push on your gas pedal, the louder your vehicle becomes and the closer to the redline you get. Now, when placed in drive, your car will automatically shift between 2 RPMs and 4 RPMs. This is shifting your car up and down gears to keep the engine inline with your moving vehicle. If you hit the redline and keep hitting it, you’ve hit your maximum RPMs and your car engine cannot go any further, which will eventually cause your engine to blow up.
Redline In Manual Vehicles-
Manual cars, however, need to be shifted manually in order to match your RPMs to your vehicle speed so your engine can switch gears and not explode! Hence why most people do not like manual cars. You have to do more work. But they are SO much more fun!!
If you’ve ever driven a manual car, I am sure you have some close to hitting, or have hit, the redline. Which is fine, just don’t do it regularly. Your RPM tachometer, on a manual car, when you start driving will increase from 0 RPMs on. If you do not shift your vehicle to the next gear, that tachometer will continue to rise. And depending on what gear you are in, you will start to notice smoke the closer to that redline you get.
Now, sometimes it’s ok to hit the redline. For example, race cars have to “max out” (hitting their rev limit) all the time to get the most oomph. This awesome video below shows exactly what I am talking about.
To sum things up, your redline shouldn’t be a worry but is something you should know about. Automatic cars really do not have to worry about this, unless you are in neutral accidentally stepping on the gas pedal. Manual cars, if driven correctly, shouldn’t have to worry either. Now, if you want to have some fun and see what your cars got, then take it out on a straight road and hit the redline!
Definitely exhilarating 🙂 But don’t tell the cops I told you so!
For more car facts, check out our section called Build Your Knowledge.