Outer Limits 4x4 Board

HI All

I installed a boost gauge in the 80series last night and fitted the boost signal line here . . .



there was a plug in the housing here, just had to tap new thread.

Anyway after taking it for a drive when giving it lots of right boot with the turbo on boost the gauge will jump up to about 14psi then immediately drop back and settle around 10 - 12 psi.
the gauge also makes a fluttering or chattering noise as boost pressure rises and again when it falls.

I am wondering wether the gauge is affected by the signal being inconsistent coz its too close to turbo (on the turbo), will I get a more stable signal if the line is plumbed into intake crossover pipe away from turbo

Any suggestions??

cheers

Mine is in the crossover pipe and doesn't flutter or peak momentarily as you have described. Although someone on here has mentioned previously having this problem. If you search, you should find it was related to a little metal piece that fits right near where you insert the pipe and it acts like a regulator for the airflow. What brand of boost gauge is it? Mine came with this regulator piece in the kit.

Even if you have set your boost to 12psi it still will boost spike momentarily until your wastegate fully opens and it settles it to your preset pressure.
I don't think it would change wether it is beside your turbo or 2 foot away as the pressure would be consistant through to your valves.
But then again I would just try a differant location and see what happens.

I believe it's best to locate the boost guage line closest to the intake manifold as possible. You then know how much boost is actually enetring your motor, which is what's important.

Err that outlet normally sends the boost signal to the wastegate.

Where's your wastegate?

I know on a 60 you can go without but.....

Paul

me3@neuralfibre.com wrote:Err that outlet normally sends the boost signal to the wastegate.

Where's your wastegate?

I know on a 60 you can go without but.....

Paul

is this how its meant to be? turbo is a reco unit fitted by previous owner so I have no way of knowing whats been done.

I have fitted a new boost controller mounted to side of air cleaner. you can see the two new peices of vaccum line that are plumbed into waste gate, water cooling lines block wastegate from veiw

solution found. I did a search and whatayah know I found a related thread

the VDO kit had a spare fitting in it so I silver soldered up the hole in the brass fitting. then drilled it out with a 1mm drill bit. the hole in the VDO fitting was about 3.5mm

swapped the fittings over and its all sweet.

Gauge responds quickly and smoothly and the rattly noise is gone








thanks for the input


Dave

The inlet manifold is the better position as it shows engine boost, the turbo boost may be 2-5 psi higher depending on the restrictions in the intake such as intercoolers, throttle bodies(petrol) and plumbing.

Joel

PGS 4WD wrote:The inlet manifold is the better position as it shows engine boost, the turbo boost may be 2-5 psi higher depending on the restrictions in the intake such as intercoolers, throttle bodies(petrol) and plumbing.

Joel

I did wonder about that when I first installed boost gauge coz gauge reading seemed to be a bit erratic. since restricting the signal line it seems to read OK.

intake pipe is stock standard, so its a pretty short run to manifold

I have tweaked the boost controller a little and wound up the boost so the peak boost was 14 psi. As soon as the gauge hits 14psi the overboost warning light comes on, pretty sure the overboost warning is triggered at 14psi. so at least they seem to correspond. factory boost/overboost signal line is plumbed into crossover pipe close to the manifold

wound the boost controller back a touch so it peaks at about 13 psi.

Dave