MAF Sensor Comparison
 

Hi there;

The idea is this; bare with me...
My build so far I am slowly building up my car for a turbo kit.
The idea is to go piece by piece so the day I acquire the kit. There shouldn't be issues the day the kit installed.

That being said; MAP sensor..

Perrin has a 2.5BAR and there are a few other companies that sell 3BAR and 4BAR.

For a DD turbo kit and building up to it. Is there a difference between the 2.5BAR or 3BAR MAP?
When should I get a 4BAR MAP?

MAP not MAF. You only "need" as high as the max boost pressure you expect to see. Don't forget that 0 Bar boost is 1 Bar MAP. The smallest you need is preferable.

2.5 bar is plenty for the boost these car take unless built motor.

Most MAP sensors are going to output a 0-5v signal. You will want the lowest pressure sensor possible to provide the most granular signal in that range based on the target boost you plan to run. If you don't plan on running 20+ lbs of boost, stick with a 2.5 bar (about 21 psi) sensor

The Omni 3 bar MAP sensor is most commonly used and is good to about 29 psi of boost (have to account for atmospheric pressure), which is more than enough for a daily driver. A 4 bar sensor is therefore highly unnecessary. Whichever one you pick, just let your tuner know so they can enter the scaling value into the tuning table.

http://omnipowerusa.com/store/Subaru...nsor-c11282089

Agreed. I have the omni 4 bar and regret it. Error on a sensor is measured as a percentage of full scale reading so you end up with larger errors in the reading than you would on a 3 bar.