I have an old MAP sensor (Manifold Absolute Pressure) sensor that has three pins "+5V…Vout…Gnd" I've pierced the back side of the MAP sensor to measure air pressure. Accuracy doesn't matter. What I want to do is mount this somewhere on the front of the vehicle and see how much wind resistance I'm getting. Remember - accuracy be damned, I don't care. I want to be able to compare the difference between open air driving versus pulling behind another vehicle. No - I don't want to tailgate. I want to see how much the pressure changes (actually hear, as I want to build an oscillator that is voltage dependent - easy enough). I'm more interested in your opinions on the mechanical aspect of it.
Like jet aircraft with their "Pitot Tube" probes on the front of the jet, air rams into the Pitot and the computer senses the wind pressure and calculates the air speed. Again, to hell with accuracy, I don't care about what my air speed is, I just want to be able to determine when I'm behind a vehicle how much difference it makes. And that "Difference" is relative. Again, doesn't matter. More wind pressure the higher the pitch. Less wind pressure the lower the pitch. I have ears that are calibrated enough for the project. I've always wondered about when there's a cross breeze and you're in the next lane to a big rig, where's the sweet spot for cruising while reducing the load on the engine.
No, I'm not trying to make a device to improve gas mileage, I just want to know when I'm pressing harder on the pedal to maintain speed versus the subtle difference it might make when following another vehicle. Another curiosity has been wind resistance on the nose of the vehicle when facing a headwind, versus a tail wind.
I've been working on building my woodshop and am tired of drywall and mudding. My shoulders ache from all the over-head sanding and mudding. So I want to take a break from that and put together an oscillator circuit that is voltage dependent. The measured range of the sensor on a 5VDC supply ranges from 0.5V to 4.5V. So somewhere in between that I need a mechanical way of sampling the air pressure on the nose of the car. Tacoma to be exact. I'm guessing that the size of the orifice will make a difference too. So your opinions please.
Like jet aircraft with their "Pitot Tube" probes on the front of the jet, air rams into the Pitot and the computer senses the wind pressure and calculates the air speed. Again, to hell with accuracy, I don't care about what my air speed is, I just want to be able to determine when I'm behind a vehicle how much difference it makes. And that "Difference" is relative. Again, doesn't matter. More wind pressure the higher the pitch. Less wind pressure the lower the pitch. I have ears that are calibrated enough for the project. I've always wondered about when there's a cross breeze and you're in the next lane to a big rig, where's the sweet spot for cruising while reducing the load on the engine.
No, I'm not trying to make a device to improve gas mileage, I just want to know when I'm pressing harder on the pedal to maintain speed versus the subtle difference it might make when following another vehicle. Another curiosity has been wind resistance on the nose of the vehicle when facing a headwind, versus a tail wind.
I've been working on building my woodshop and am tired of drywall and mudding. My shoulders ache from all the over-head sanding and mudding. So I want to take a break from that and put together an oscillator circuit that is voltage dependent. The measured range of the sensor on a 5VDC supply ranges from 0.5V to 4.5V. So somewhere in between that I need a mechanical way of sampling the air pressure on the nose of the car. Tacoma to be exact. I'm guessing that the size of the orifice will make a difference too. So your opinions please.