boost gauge wrong or plumbed in wrong?

[gttjames]

My standard gauge goes just into the white marks - my boost gauge peaks at 14psi (i have it plumbed in so it reads vacum aswell so from the dv vacum pipe t piece)

At work we have a pressure tester so i put it onto actuator - pumped up and it held until 16/17psi untill it opened. So im running 17psi then? Is my boost gauge plumbed in correctly or is there a better place to go from. Or is it the gauge is slightly out and i need a new 1? Have had the gauge for over 5 years so...

[Brigsy]

Pressure drop through the carb/intercooler will be a few psi. Your gauge is probably OK.

I personally take the manifold boost pressure as how much boost the engine actually sees.

[gttjames]

:confused:

i have a vac hose coming from the dv to a t piece, off that it takes off to the AEI and to another t piece - this takes off to inlet manifold and my boost gauge.

So i am reading from manifold and from aei line, is it plugged in wrong then?

[Tony Walker]

no, but imagine the exhaust gas pressure on the exhaust wastegate along with the boost pressure on the actuator. the pressure in the turbo housing probably helps it open a couple of psi sooner i should imagine?

[gttjames]

bit confussed about what boost im actually running. Looked into it abit more, my standard boost gauge doesnt even go into the 'lines' - going by the boost gauge image on the other forum

http://www.renault5gtturbo.com/maintenance.htm

mine goes between d and e - meaning 12.5/13psi
My boost gauge plumbed into aei line reads 13psi

So standard gauge and my boost gauge both give the same figure - yet my actuator can hold 17psi - am i running 17 or 13? :confused:

When people talk about running 15psi on standard cars etc are they doing this off a gauge in which case they could be running 20psi at actuator? And again people who are running 20/21psi which im aiming for are they taking that reading from the boost gauges or from the actuator.

cheers guys

[Nialle]

Mine is T pieced in to the hose going to the aei, think thars where most people put them

[Brigsy]

Dont even bother trusting the standard gauge mate. If your boost gauge reads 14psi on the aei line then thats what your running, i.e. thats how much boost the engine sees.

[gttjames]

Dont even bother trusting the standard gauge mate. If your boost gauge reads 14psi on the aei line then thats what your running, i.e. thats how much boost the engine sees.

thats what i need to know, cheers guys!

also if my boost gauge iv plumbed in and the standard gauge both show the same reading maybe the standard gauge is reading fine currently

[Jonny5]

maybe the standard gauge is reading fine currently

The standard dash gauge measures from the top of the carb so should be slightly higher than a boost gauge in the aei line, which measures boost pressure at the manifold.
Either way just only watch your aftermarket boost gauge like brigsy said ;)

[Renault 5 GT Turbo]

So it is clear the standard gauge gives a slightly optimistic reading given where the vaccumme feed is taken from. If you look at the peak boost on the standard guage on the 0-60 advert, you can see where it should peak.

[Jonny5]

So it is clear the standard gauge gives a slightly optimistic reading given where the vaccumme feed is taken from. If you look at the peak boost on the standard guage on the 0-60 advert, you can see where it should peak.

http://i1066.photobucket.com/albums/u410/JonnyR5-2008/4400bdc7.jpg

[gttjames]

Thats where mine peaks now (actually slightly less), never goes into those lines

[juha5gtt]

New poster! (less than 10 posts)


Well not sure but its seems that phase 1 and phase 2 models have
little different oe boostgauge becouse if you look advert and http://www.renault5gtturbo.com/maintenance.htm (http://www.renault5gtturbo.com/maintenance.htm)
gauge their have little different red thin lines starting angle.
So advert picture is little less than max 0.8 bar carb top and
thats phase 1 model. Also Original (non-tuned) phase 2 cars
gauge goes same angle and thats D marked. When its does
approx. red 5 thin lines down then its 1 bar boost carb top.
But pref. aftermarket gauge is more accurate.
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