DEFI Blue Racer 52 mm Boost Gauge / OPOD Mono OSIR pod inc fitting

[john_o]

cmdrfire : the gauges are imported anyway so I reckon you could get the metric variant just as easily.

TC : appreciate the comments. you must have taken your nice pills today 

[john_o]

edited to add wiring pic 

[SteveS]

very helpful!

[Mark_GTIV]

I had Defi meters fitted to my Subaru WRX with the control box fitted, so you could play back your run, you could read peaks, set audible and visual warnings etc... they were excellent.

As you can see they do support metric versions of the clocks. I had exhaust temp (i had the probe in my downpipe), oil temp and boost. I notice that you can get an enclosure that replaces the air vent on the top of the dash, with something like I had for the WRX.

The whole kit is a little expensive, but if you've made some bigger modifications - these are a must.








I had the control unit discretely mounted under the steering wheel.

[xxx_mojo_xxx]

Had my DEFI gauge fitted today...generally pleased with it. Shame that the blue back light doesn't exactly match the OEM blue.

Did anyone figure out how to get the dimming function to work without cutting any wires?  Apparently, I need to find a 12V feed from the lighting circuit?  For the moment, its set to full illumination which is a bit too bright during the night....

P.S. My gauge peaks at around 21psi... can anyone explain what the inHg and psi values mean?

[john_o]

i have run mine as 'night dimmed' from day1 
never got any further on tapping into the dimmer feed as I dont like it any brighter (even during the day)

inHg - inches mercury for vacuum
psi - poundsPerSquareInch for positive pressure

[cmdrfire]

Men use BAR.

[xxx_mojo_xxx]

i have run mine as 'night dimmed' from day1 
never got any further on tapping into the dimmer feed as I dont like it any brighter (even during the day)

inHg - inches mercury for vacuum
psi - poundsPerSquareInch for positive pressure

Thanks, John_o.  So what how does vacuum vs positive pressure affect boost?

[john_o]

thats a whole bigger subject but positive pressure IS boost
(i.e. you can cram more air using the exhaust driven turbocharger , and therefore more fuel into the engine = bigger bang = more power)
vacuum is the opposite condition usually when your foot is off the throttle and the pressure is negative.

only a forced induction car will show a positive large 'boost' value, but both a forced induction car and a normally aspirated will show vacuum values

my very simple 2p 

[xxx_mojo_xxx]

So, why doesn't my boost shoot into the PSI section of the gauge everything I press the peddle. 

I always get movement in the gauge needle...but some times I can be ragging it and the dial simply moves in the lower part of the gauge, i.e. the 0-30 inHg.

Other times,  the needle moves straight into the 0-30 psi bit...

Or is there something wrong?

[john_o]

there are some conditions where youll be in an inbetween 'phase'
(+ = psi/boost , - = mmHg/vacuum)
cruising at 85mph mine sits at -10 (i.e. its a part throttle)
general driving on light throttle I'm barely ever in +ve side

if you are on full or medium throttle you should be registering some + boost from any rpm.
going down a slip road under light throttle in 4th/5th I can make good progress and the guage registers around 5 psi
you cannot achieve large boost values at very low rpm (as the exhaust gases arent making the turbo spin fast enough)

if you were 'ragging' it , then I would always expect you to either be WOT(boost) or lift off (vacuum) , so yes you should see some boost all the time.
BUT if you go WOT in 6th gear from low rpm dont expect huge psi values.
below 2000rpm expect 3-5 psi then it should build quickly to peak around 2700 rpm (depended on the turbo you have)

as an experiment , try a straight empty road , be safe!, 3rd gear 50mph (what rpm is this)? and try going on and off the throttle to WOT , the guage should immediately go into the +ve side each and every time without fail, then back into -ve when you lift off
if it doesnt then yes you have a problem.

have you fitted an forge DV ?
do you have access to someone with VCDS who can log the car ?

let us know how you get on

[xxx_mojo_xxx]

Thanks John_o - from your description the boost gauge/turbo appears to be working as expected.

Got a Forge DV valve.
No access to VCDS - is there anyone nearby?
And, what is WOT short for?

[john_o]

 
check out the VCDS section where theres a list
WideOpenThrottle 

[xxx_mojo_xxx]

Cheerz!