Boost gauge & controller install...

[InVinceble]

I've read all the old posts and you guys don't make it easy
For my 3.1 "Bighorn" where is the best place to fit a line for my new boost gauge? Before or after the intercooler?
I thought I would tap a hole into one of the plates which cover up where the EGR valves used to be, and take the line from there.
With that done, my bleed type boost controller is a simple tee into the hose running to the wastegate actuator, is it not?
Go on, put me right

[geeves]

Its a very interesting and difficult question.
For the boost controller it needs to go in the short hose between the turbo and waste gate. On mine this is a straight hose about 90mm long.
For the boost gauge your idea would give the purest answer as it is the actual boost as it goes into the cylinder but it can give very strange readings at low or no boost. On mine conected like this the needle vibrates so vilently you cant see it at idle. On mine there is a presure line that goes from the inlet side of the intercooler to the top of the fuel pump. Ive put a T piece in this line for my gauge. The T piece suplied with the gauge has a restrictor in the line used for the gauge. If I hook my gauge direct to the outlet on the intercooler or conect it to the wastegate pipe I get 17psi but huge needle vibration at idle. Useing the T with the restrictor in the line to the pump I get 14psi and a rock steady needle.
Mine is the 2.8 Not all the 3.1s have this line conected to the intercooler but there will be a line to the fuel pump from the boost side of the turbo. In my mind this would be the best line to T into

[geeves]

In theory it shouldnt matter where the input for your gauge comes from but you do get a pressure drop even in a straight pipe so the closer you can get it to the intake valves the better but its probably not worth drilling extra holes etc as there are several feeds already that will do the job.
I think it is very inportant though to use a T piece in the hose you cut into that has a restrictor though. I tested all this as a side issue while trying to track down a boost loss in my wagon. It turned out to be a 1cm split in the hose that was feeding the gauge and pump boost compensator. This restrictor is a sleeve in one leg of the T with a 0.5mm hole The other 2 legs have a full 3mm hole. Without this the gauge is unreadable at idle

[InVinceble]

Hmmmm, now you have stumped me!
I've gone for the hole in my EGR blanking plate and fitted the gauge to that.
Are you ready.....
No issues at all. Dead steady needle at idle, smooth sweep to max. boost.
I'm getting 11psi tops. Does that sound right?
Turbo is making an awful racket, first time I've really stopped to listen to it with the bonnet up. Hopefully my hybrid turbo will be finished for the weekend - that will be continued in another thread.
As for the boost controller, need more hose to complete!

[geeves]

If the needle is steady you must of spent more on your gauge than the rest of us. 11psi is normal for a 3.1 but this can be tweeked a little. If the noise the turbo is making is a squeal on shutdown then I would put some urgency into the hybrid project. Fairly soon the noise will stopp suddenly maybe with a little smoke

[agin]

I do not know if it helps but my friend filled some oil into the hose of boost gauge to overcome needle vibration

[geeves]

oil would work if you have a problem but try without first.

[InVinceble]

Geeves - trademe & and eye for a bargain! ;D
Oh, and I should mention the mates that told me to get a boost only gauge.