Which Instrument

[neil_jdmr]

Which instrument is going to be the most accurate for my boost reading\'s
 
My aging blitz boost gauge, or
 
the pfc commander
 
I know the commander takes a reading from the map sensor and the gauge take it from the uim, but i cannot see the calibration in the boost gauge being all that accurate but on the other hand i cannot see the map sensor being the best place to gain a boost reading either.
 
So whats best.
 
The reason i ask is my gauge shows pretty much 1bar and the pfc shows 0.9bar and at this boost level im seeing a max of 92% inj duty, so i guess its closer to 0.9 as i though 1bar would max out stock fuelling.
 
Ideas/opinions please,

[Bobbit]

Trombone? Sorry.

[Prof]

The reading off a mechanical boost gauge has to be the most accurate - I say that because the MAP sensor could be subject to offsets caused by poor earthing.
 
The MAP sensor uses a 5V reference from the ECU, and provides a voltage output relative to it\'s earth point - but that might not be the same earth as the ECU is using.
 
I\'ve found errors as much as 0.5V on the earth line - it\'s important to reference the map sensor ground with the ecu ground.

[m1tch]

Mechanical boost guage is best as it reads the actual boost to move the needle and not needing electronics to tell it what it thinks the boost is lol

[Jono FD3]

another thing to remember, the Commander needs to be told when 0psi is on the initial mapping/setup or it could over/under read!!

Jono

[neil_jdmr]

Im sure pip will have done that,