MS3 Ultimate Map sensor

[WilkieLSx]

Starting to wire up my MS3pro Ultimate with 24x harness in my car, not sure if I should use the 4bar MAP that is included on the ecu or wire in my 3bar that I have. I'm only planning to run 18-22lbs of boost so the 3bar would be enough but it might me easier to just use the internal 4bar. Would there be any benefit to wiring in the 3bar over using the 4bar? just thinking that the tighter range would make for a clearer signal or maybe Its a non issue and I'm wasting my time. thx

[CRSTune]

The 3 bar will have more resolution for your application. It can also remove the need to run a vacuum line into the cabin (or wherever the ECU is). With that said, if you want to cut down on unnecessary extras, you could remove the 3bar and run the internal 4 bar. Honestly, it's completely up to you.

Personally, I'd run the 3 bar so that I wouldn't have to run a vacuum line into the cabin.

[WilkieLSx]

ya I might just hook up the 3bar, Im hoping future firmware updates will let me use the 4bar for dome pressure but I was told currently I cant. I was brain farting there and couldn't think of the word resolution to describe what I meant.

[nathaninwa]

My experience, running a 4 bar sensor. I knew I was going to turbo my LS so I installed a 4 bar sensor while I was all motor. Setup didn't skip a beat

My 2jz runs something like 340kpa at times, so it runs the same 4 bar sensor (I keep things alike amongst my LS installs in case I need to rob parts, hence the LS running a 4 bar at 20psi tops) and that car runs mostly in vacuum and in 5 years and 20k miles I have had no issues with map resolution Car actually runs great, get near 27mpg and makes a crap ton of power

[CRSTune]

I've also run a 4bar MAP sensor while NA knowing I'd have a turbo down the road. I had no problems with the accuracy of the readings and my car ran great.

5V resolution is nice but what matters more is the resolution of the ADC count of the ECU (how the ECU interprets the voltage signal). If I'm not mistaken, that's 1024 ADC counts for MS. So, for a 400kpa sensor, that's 0.391kpa/ADC vs a 300kpa sensor at 0.293kpa/ADC. That's not a whole lot of difference.

[nathaninwa]

I get it, running 2-1/2 bar on an4 bar sensor is way better than just running all motor. And with lots of ms3's running the map daddy setup and those of us like me with a street car running an external it will be just fine from a practical stand point. I realize there is lots of inputs and outputs now, and the ability to use the internal as done pressure may or may not come. So I'd run the internal on the Pro and wire in an external for dome and save I/O, because before you know it, they'll all be gone with the way we do things

I'm wiring in a micro to pro and still don't have enough analog inputs to datalog what I would like to

[jsmcortina]

ya I might just hook up the 3bar, Im hoping future firmware updates will let me use the 4bar for dome pressure but I was told currently I cant.

The internal sensor is already in the list, but don't. For Dome Control you must use a sensor as close to the wastegate as possible. Any length of hose delays the signal (3ms per metre) and reduces control accuracy.

James

[Motoren]

I'm about to wiring the ms3pro ultimate and have a question reguarding the 3ms/meter delay on the map hose length.

It's not a problem using the internal map sensor with around 2 meter hose compared to external map sensor with 1/2meter hose ?

Kent