I received my cable today, so i went to log some info. My boost is 47.79 enlighten me please, I have an 06' Evo IX MR SE, with the following mods:
Injen uicp
Injen intake
Injen 3" downpipe
High flow cat
HKS power exhaust
my boost gauge reads 24psi so am i missing something here, even if i add 14.7psi to get absolute it still doesn't make sense.

 

South Jordan huh? You're not far from me

The stock boost sensor only reads up to like +2psi IIRC, so you can not log accurate boost with it. Many people here have used the 3bar JDM map sensor as a direct replacement (with a few ECU changes in ECUFlash), and others have used the GM 3 bar.

 

ZT-2 also does a good job of logging. I have both a ZT-2 and a JDM map sensor, but I plan on going Ecu controller boost in the future.

 

So what all do i have to buy so i don't get bogus info?? why does anybody buy this if it gives crap numbers?

 

Not giving crap numbers. It just reports the voltage that it sees and the stock MDP sensor shows 4.8-4.9V at about 2psi. Switching to the JDM 3 bar map is the only way to log boost with factory equipment and Evoscan. Then you are good to about 33 or so before it maxes out

 

How much is a JDM 3 bar map sensor? and where can i get one?

 

Someone on this forum (I think MRFred?) sells them, and I believe they're around $125.

If you're planning on doing any real tuning, you may want to look into a zeitronix wideband and then get the MAP sensor for it. You're probably looking about ~370 for that option, but at least you'll know your true A/F ratio and your real boost, not just gauge boost.

 

https://www.evolutionm.net/forums/sh...ight=log+boost

 

Not sure what you mean about real boost and gauge boost. The JDM MAP sensor, like any other MAP sensor, reads absolute boost. Gauge boost is what everyone thinks of when they think of boost. Its the absolute boost minus the local atmopheric pressure.

 

I think he's referring to a standard 52mm mechanical gauge vs. a MAP sensor style gauge. As we've seen by a recent post, the JDM 3 bar map sensor and the zeitronix sensor both log the exact same results, which is darn good since the zeitronix boost sensor is accurate to 0.1 psi so the JDM sensor is too.

You really can't go wrong with either MAP sensor but I'd suggest buying the JDM sensor if you ever plan on using it to aid with ECU based boost control. The Zeitronix is good if you want a 'heads up' display of your Map sensor boost level.

 

Yah, I guess I didn't clarify on that very well. I was referring to that, as well as the fact that what your gauge says usually is not going to line up with what the pressure actually is (usually off by a few PSI).

 

Yeah, mechanical gauges like those offered by Autometer have a spec of +/- 1.0 psi where as the zeitronix is rated at +/- 0.1 psi. Huge difference there,lol.