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Double The Boost Reading Wtf?!

YCOPY

By YCOPY,
in Engines & Forced Induction

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YCOPY Enthusiast

YCOPY

Posted
Posted

Ok, so I have a strange issue...

I have a HDi SBC-D-EVOLUTION bought it brand new from HDi earlier this year, when I had this installed I took the car to the dyno just to set it up and do some runs.

I found that the controller / gauge is reading 18.5 psi...and the dyno printout is reading 9psi. so the HDi is reading what seems to be double!

So I have installed a autometre mechanical gauge in and yep, I only get 9psi.

Now ive spoken to HDi and tried everything they have asked, ive had it re wired several times,moved the vac lines used "specific" VAC lines also. so after ive done all this still no good...

last week i sent it away to HDi and they have tested it and told me that the gauge and the controller are working 100% perfect and to check my wiring as it must be that...I had it reinstalled again on the weekend and its still reading double the boost!!

Has anyone had this sort of issue?? how the hell can it read double the boost!

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YCOPY Enthusiast

YCOPY

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see thats what i dont get..dyno was9,my mechanical gauges all read 9 but the HDi reads 18.5...the vac part of the gauges all read the same @near on 20Hg but the moment you boost they are different.

Im half tempted to take it out and stick it in my daily thats not turbo and see if it produces some strange reading...its just such a pain in the arse!! all this time on it and HDi are telling me its perfect and its clearly not..

YCOPY Enthusiast

YCOPY

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Ive had it @ the nipple off the cooler pipe,off the FPR,off the back off the plenum where the stock gauge feed is from. its on the FPR @ the moment as thats how HDi asked it be installed..

Ive even had it in the same line as the mech gauge but was told by HDi to take that out as that could cause the issue..

What are you using as the pressure source for the HDI unit?
Moodles2 Grand Master

Moodles2

Posted
Posted

Sounds like HDi only checked the gauge was working, not that it was calibrated. Really need an aircompressor set to 9psi supplying air through a hose to the HDi gauge to prove its calibration is way off.

count_rye Apprentice

count_rye

Posted
Posted

A proper calibration is needed for 'zero' and 'span' for both the gauge pressure and absolute pressure. A pressure transducer also needs a stable power supply, a good multimeter may come in handy at these kind of situations. Calibration also includes a reference gauge or more often called a Master Gauge to tell whether the supplied(simulated) pressure and current(mA) are calibrated with each value.

Cheers.

YCOPY Enthusiast

YCOPY

Posted
  • Author
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So is there somwhere i can get this tested?? or am i best to chuck it in the bin now and be done with it...

A proper calibration is needed for 'zero' and 'span' for both the gauge pressure and absolute pressure. A pressure transducer also needs a stable power supply, a good multimeter may come in handy at these kind of situations. Calibration also includes a reference gauge or more often called a Master Gauge to tell whether the supplied(simulated) pressure and current(mA) are calibrated with each value.

Cheers.

count_rye Apprentice

count_rye

Posted
Posted

Basically, it's best to have the manufacturer calibrate it for they know the zero and span adjustment of the component but if you know someone(preferrably a friend) with an electrical/electronic/control engineering background, with a master gauge, compressed air source, a multimeter, and possibly a current simulator, he could easily calibrate that at a cost of a burger,hehe If it still works but out of range, it can be fixed.

Im here in Dubai, dont know where in Australia you could find that someone aside from the maker, sorry.

Goodluck though, mate.

YCOPY Enthusiast

YCOPY

Posted
  • Author
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Ah ok cool, i work in an engineering company (im in IT)... i will ask the guys tomorrow.

Thanks for you help :P

Basically, it's best to have the manufacturer calibrate it for they know the zero and span adjustment of the component but if you know someone(preferrably a friend) with an electrical/electronic/control engineering background, with a master gauge, compressed air source, a multimeter, and possibly a current simulator, he could easily calibrate that at a cost of a burger,hehe If it still works but out of range, it can be fixed.

Im here in Dubai, dont know where in Australia you could find that someone aside from the maker, sorry.

Goodluck though, mate.

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