Fixing the stock boost gauge?

[QuietRonin]

I'm the kind of person who likes any modification to look stock. Nothing's worse than having something stick out or not match with the rest of the interior.

So i'm wondering, has anyone tried rewiriing or modifying in some way, the stock boost gauge so it will be more accurate? I can't find any info on this, so the smart bet is that it's been tried and can't be done, or it's just easier to get an aftermarket boost gauge.

Thanks.

 

[MattUnderwood]

If you don't like the gauges sticking out, you could always just get the vent holder because thats what I have and it keeps them somewhat hidden. I hated having the tripod look. The gauge cluster holder would be your best bet I think

 

[steve]

it's just easier to get an aftermarket boost gauge.

To actually turn the factory boost gauge into a real boost gauge you'd need a MAP sensor and some circuitry to drive the gauge or code for the ECU (and an EPROM ECU) and you would still be left with the limitations of the labeling on the factory gauge.

 

[ramsack]

I would be easy, and one could make a new overlay for the gauge for a better range. It is just driven off voltage level, not any kind of crazy PWM signal. i've always wanted to get rid of the gauge and make a 3914 or 3915 barcode circuit to run off that ECU output instead.

 

[steve]

It is just driven off voltage level, not any kind of crazy PWM signal.

The ECU actually uses a PWM signal to make that voltage but your correct, the gauge itself is using a voltage to drive the meter.

Even with a new label your still limited in how far the needle swings compared to a aftermarket gauge.

 

[QuietRonin]

The ECU actually uses a PWM signal to make that voltage but your correct, the gauge itself is using a voltage to drive the meter.

Even with a new label your still limited in how far the needle swings compared to a aftermarket gauge.

Even with stock boost levels? Personally, i'm planning to do little more than a 14b swap. Maybe a couple of the free mods.

 

[habitatguy187]

I local here replaced his stock gauges in the cluster with real gauges. Coolant temp, boost gauge, and oil pressure. He really took his time and it looks great, I'm sure it was a bit of a pain though.

 

[QuietRonin]

How do aftermarket boost gauges work? Could parts from one be used to suppliment the stock gauge?

I'm just trying to throw out ideas. I'm good with the mechanical side of cars, not so much the electrical side.

Or, I may just be trying to keep a dying dream alive.

 

[steve]

There are two major categories of gauges, mechanical and electrical.

The mechanical pressure gauges typically use a Bourdon tube with a gear arrangement to move the pointer. Pressure measurement - Wikipedia, the free encyclopedia Most boost gauges are simple mechanical ones with a pressure port in the back.

The electrical gauges use either a air-core motor or a stepper motor movement (in the newer expensive gauges) to drive the pointer.

Air-core meters use the current from the sensor to directly move the pointer where stepper needs logic to interpret the sensor data and then step the pointer to the correct position. Both types need some sensor to convert the pressure to a signal the gauge can interpret. Electrical boost gauges typically use a MAP sensor for this.

The DSM gauge cluster uses electric air-core meters for the boost, temp, tach and fuel gauges. The boost gauge is driven by the ECU based off the airflow read from the MAF and throttle position to approximate the vacuum or boost pressures.

Short of disassembling an existing electrical boost gauge and sticking it's guts in the cluster, you are building your own electrical boost gauge using the existing air-core meter from the boost gauge and a new MAP sensor.