Boost pressure

Sweety · 31-01-2015, 01:48

On a 2.7TDI T2 am I right in thinking the standard boost pressure should be around 0.9bar / 12-13psi ? The reason I'm asking is my old gauge used to show 1.2bar but the new gauge is showing 0.75bar

now I'm sure the old gauge was over reading a bit & at time would get to 1bar then jump to 1.2. What I noticed when fitting the new gauge was the T that came with it had a brass insert with a tiny hole in it on the part that the hose fits on to go to the gauge but the old T didn't have this so was wondering if the full boost pressure isn't reaching the gauge:

if it makes any difference the new gauge uses 3mm ID hose where the old one had 3mm ID 3.5" long which went into a brass fitting & had 1mm semi ridged pipe coming out of it to the gauge only thing I can think of is poss swapping over the It's to see if that makes any difference

Sweety · 31-01-2015, 14:59

Well changed the T piece & the readings are still the same so must have a gauge that likes to under read

was going to tweak the boost a little but the lock nut is stuck fast so was scared to keep trying in case I bent the rod

what's the best way of doing it hold the rod with a pair of vice grips whilst slackening the lock nut

& how many turn of the rod will I need just want to up it a bit but not to the point I start to run lean fuel wise

Banshee · 31-01-2015, 16:20

Quote:

Originally Posted by Sweety

Well changed the T piece & the readings are still the same so must have a gauge that likes to under read

was going to tweak the boost a little but the lock nut is stuck fast so was scared to keep trying in case I bent the rod

what's the best way of doing it hold the rod with a pair of vice grips whilst slackening the lock nut

& how many turn of the rod will I need just want to up it a bit but not to the point I start to run lean fuel wise

Dude get some pics up and that, I want to do this mod

rustic · 31-01-2015, 16:50

I fitted a boost gauge to mine, but there was quite a lot of turbo noise transmitted to the dial assembly, so I fitted a restrictor in the line to the meter, and this stopped the noise, and didn't affect the meter accuracy, or speed of response.
So maybe this answers the query of why a plug with a fine hole was fitted on one of your meters.

Banshee · 31-01-2015, 19:20

Quote:

Originally Posted by rustic

I fitted a boost gauge to mine, but there was quite a lot of turbo noise transmitted to the dial assembly, so I fitted a restrictor in the line to the meter, and this stopped the noise, and didn't affect the meter accuracy, or speed of response.
So maybe this answers the query of why a plug with a fine hole was fitted on one of your meters.

Different with yours though bud as you just "T" piece off the vac pipe near the actuator don't you?

The TDi's are different but I really want to fit one

rustic · 31-01-2015, 19:33

Quote:

Originally Posted by Banshee

Different with yours though bud as you just "T" piece off the vac pipe near the actuator don't you?

The TDi's are different but I really want to fit one

Yes I "T'd" off the small pipe that connects to the aluminium pipe that has TURBO on it. No intercooler on mine.

Banshee · 31-01-2015, 19:43

Quote:

Originally Posted by rustic

Yes I "T'd" off the small pipe that connects to the aluminium pipe that has TURBO on it. No intercooler on mine.

You've got the easy life, it's a lot more involved with the TDi I'm led to believe

solarman216 · 31-01-2015, 20:49

the small hole on the tee piece is simply to make the gauge read steady rather than jump about, adjusting the waste gate spring will not alter the pressure, it will just raise the pressure that the gate opens and that is only at the extreme end of the range, if your pressure is low then it may be that the waste gate is leaking, or the turbo is goosed, but if performance and mpg are good then why worry, Rick

Banshee · 31-01-2015, 20:55

Quote:

Originally Posted by solarman216

the small hole on the tee piece is simply to make the gauge read steady rather than jump about, adjusting the waste gate spring will not alter the pressure, it will just raise the pressure that the gate opens and that is only at the extreme end of the range, if your pressure is low then it may be that the waste gate is leaking, or the turbo is goosed, but if performance and mpg are good then why worry, Rick

I think it's just the novelty Rick

That's why I want to do it anyway

Sweety · 01-02-2015, 14:54

Quote:

Originally Posted by solarman216

the small hole on the tee piece is simply to make the gauge read steady rather than jump about, adjusting the waste gate spring will not alter the pressure, it will just raise the pressure that the gate opens and that is only at the extreme end of the range, if your pressure is low then it may be that the waste gate is leaking, or the turbo is goosed, but if performance and mpg are good then why worry, Rick

TBH Rick don't think there is any problem with the turbo as it pulls well & it's only done 61K, just the gauges are giving different readings

rayf3262 · 01-02-2015, 15:14

I once checked a pressure gauge by inflating a tyre to a known pressure, then used an old inflator adapter to connect the tyre to the gauge under test....

Lazy-Ferret · 01-02-2015, 15:36

Quote:

Originally Posted by rayf3262

I once checked a pressure gauge by inflating a tyre to a known pressure, then used an old inflator adapter to connect the tyre to the gauge under test....

That's how I reset my one back up after taking it all apart to change the lighting inside it.

I used the trailer tyre, set it to 10PSI (My gauge is in PSI) with the tyre gauge, checked the meter before I took it apart, then once all back together, I connected it to the tyre before putting the needle back on. Seemed to work fine.

Sweety · 01-02-2015, 17:33

Great idea guy's i'll have to dig out some tubing & an adaptor

Sweety · 01-02-2015, 17:35

Quote:

Originally Posted by Banshee

Dude get some pics up and that, I want to do this mod

Here you go Banshee pic of it plumbed into the turbo

Sweety · 01-02-2015, 17:35

Closer pic

31-01-2015, 01:48	#1
Sweety Senior Member Join Date: May 2013 Location: Northumberland Vehicle: Terrano 2.7TDI SE LWB Posts: 3,604	Boost pressure On a 2.7TDI T2 am I right in thinking the standard boost pressure should be around 0.9bar / 12-13psi ? The reason I'm asking is my old gauge used to show 1.2bar but the new gauge is showing 0.75bar now I'm sure the old gauge was over reading a bit & at time would get to 1bar then jump to 1.2. What I noticed when fitting the new gauge was the T that came with it had a brass insert with a tiny hole in it on the part that the hose fits on to go to the gauge but the old T didn't have this so was wondering if the full boost pressure isn't reaching the gauge: if it makes any difference the new gauge uses 3mm ID hose where the old one had 3mm ID 3.5" long which went into a brass fitting & had 1mm semi ridged pipe coming out of it to the gauge only thing I can think of is poss swapping over the It's to see if that makes any difference

31-01-2015, 16:50	#4
rustic Senior Member Join Date: Feb 2007 Location: Staffordshire Vehicle: Maverick Mk I 2.7 TD LWB Posts: 7,825	I fitted a boost gauge to mine, but there was quite a lot of turbo noise transmitted to the dial assembly, so I fitted a restrictor in the line to the meter, and this stopped the noise, and didn't affect the meter accuracy, or speed of response. So maybe this answers the query of why a plug with a fine hole was fitted on one of your meters. __________________ Ford Maverick GLX 1995 2.7TD LWB in illusion silver, 98k miles. Owned since new, for 22 years. Best car I have ever owned. Just wish I could drive it more.

31-01-2015, 20:49	#8
solarman216 Off road maniac Join Date: Dec 2009 Location: Bexhill on Sea Vehicle: Y60 Patrol Me, 3 ltr Mrs Posts: 17,431	the small hole on the tee piece is simply to make the gauge read steady rather than jump about, adjusting the waste gate spring will not alter the pressure, it will just raise the pressure that the gate opens and that is only at the extreme end of the range, if your pressure is low then it may be that the waste gate is leaking, or the turbo is goosed, but if performance and mpg are good then why worry, Rick __________________ Ex banger racer now off road maniac Lokka on the front with manual hubs Diff lock on rear 3 inch SS straight through exhaust Manly winch bumper with 13000 lb winch 10 spike ground anchor, with multiple straps and blocks Super strong body cills capped with scaffold pole 20% stronger springs all round aggressive off road tyres on wheels so just swap. Aim to get stuck and be completely self sufficient in extraction, love getting muddy, 2ft deep is good but rare.

01-02-2015, 15:14	#11
rayf3262 Senior Member Join Date: Nov 2009 Location: Norfolk, Poringland NR14 Vehicle: Terrano 3.0 SVE 2002 Posts: 1,549	I once checked a pressure gauge by inflating a tyre to a known pressure, then used an old inflator adapter to connect the tyre to the gauge under test.... __________________ Remember what the dormouse said: Feed your head....

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31-01-2015, 14:59	#2
Sweety Senior Member Join Date: May 2013 Location: Northumberland Vehicle: Terrano 2.7TDI SE LWB Posts: 3,604	Well changed the T piece & the readings are still the same so must have a gauge that likes to under read was going to tweak the boost a little but the lock nut is stuck fast so was scared to keep trying in case I bent the rod what's the best way of doing it hold the rod with a pair of vice grips whilst slackening the lock nut & how many turn of the rod will I need just want to up it a bit but not to the point I start to run lean fuel wise

01-02-2015, 17:33	#13
Sweety Senior Member Join Date: May 2013 Location: Northumberland Vehicle: Terrano 2.7TDI SE LWB Posts: 3,604	Great idea guy's i'll have to dig out some tubing & an adaptor