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Discussion Starter · #1 ·
Hello there,

i installed my neusouth boost gauge today on my mk4 150 still not remap. the idle is reading 10 psi and drop to 7psi when boosting.

i think i have a boost leak, but how should i know???

on cold and when it is warming the iddle read 10hg and drop to 20 when the car get warm???

is this normal??

thanks in advance,
 

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Hi Mate,

Sounds like it's running pretty much ok. It should read around -18 to -20hg when at idle. When boosting, you should be looking at 7-10PSi if standard, so that's about right. When on boost, the car should spike up at around 10PSi standard, then slowly fall off as you go up through the revs. It should also boost slightly harder in the higher gears as the engine is under more load.

Wigster.
 

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Discussion Starter · #3 ·
Hi Mate,

Sounds like it's running pretty much ok. It should read around -18 to -20hg when at idle. When boosting, you should be looking at 7-10PSi if standard, so that's about right. When on boost, the car should spike up at around 10PSi standard, then slowly fall off as you go up through the revs. It should also boost slightly harder in the higher gears as the engine is under more load.

Wigster.
that is exactly what is happening with me , so i guess i am safe, i can wait getting mu k04-001 and remap it.... ouffffffffff...... i can wait mate...

thanks a lot for your help!!! [:)]
 

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Ha ha, yeah, better turbo is the way forward! I run a K03s hybrid with custom stage 2 map and love to watch the guage spike at 26PSi. [:D]

At least you know there shouldn't be any problems with it at present.

Wigster.
 

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Hello there,

i installed my neusouth boost gauge today on my mk4 150 still not
remap. the idle is reading 10 psi and drop to 7psi when boosting.
Hi Mate,

Sounds like it's running pretty much ok. It should read around -18 to -20hg when at idle. When boosting, you should be looking at 7-10PSi if standard, so that's about right. When on boost, the car should spike up at around 10PSi standard, then slowly fall off as you go up through the revs. It should also boost slightly harder in the higher gears as the engine is under more load.

Wigster.
that is exactly what is happening with me , so i guess i am safe, i can wait getting mu k04-001 and remap it.... ouffffffffff...... i can wait mate...

thanks a lot for your help!!!
Could have fooled me!
 

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Discussion Starter · #8 ·
Hello there,

i installed my neusouth boost gauge today on my mk4 150 still not remap. the idle is reading 10 psi and drop to 7psi when boosting.
Hi Mate,

Sounds like it's running pretty much ok. It should read around -18 to -20hg when at idle. When boosting, you should be looking at 7-10PSi if standard, so that's about right. When on boost, the car should spike up at around 10PSi standard, then slowly fall off as you go up through the revs. It should also boost slightly harder in the higher gears as the engine is under more load.

Wigster.
that is exactly what is happening with me , so i guess i am safe, i can wait getting mu k04-001 and remap it.... ouffffffffff...... i can wait mate...

thanks a lot for your help!!!
Could have fooled me!
Ok Mate!!!

no it is not spiking so quickly, it is going up fairly to 10 then drop slowly to 7 psi, so i guess it is ok on standard car.
 

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Discussion Starter · #9 ·
i have notice that when i am driving the car on any gear without accelerating the idle read 22~25 hg and on neutral it read 20~22 hg.

is this normal???
 

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Discussion Starter · #11 ·
thanks mate.

my pal is a mechanic he will rant me a N75J to try it and check if i benefit any additional boost [:)]
 

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Discussion Starter · #13 ·
You will be lucky, the ecu controls the boost.
the N75J controls the wastegate and they say it gives more boost, i could not get today as i had a lot of work to do.

i think tomorrow, hope so [:)]
 

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Discussion Starter · #15 ·
I cant see how it will give you more boost. The ECU has a preset boost pressure (standard 7psi) and will tell the N75 valve what when it detect 7psi, to open the actuator. so in theory, more boost is pretty impossible?

See where im trying to come from.
what you say make sense, however i thought the standard car boost for 10psi on 150pd and 12psi on 180pd.

in addition, as i read on many forums, when the ECU give the order for the n75, the n75 controls the wastegate and close it. the n75j makes the same but is a bit slower in closing which gives you a bit more boost lets say 1~3 psi. however the n75j in not recommended by many tuner especially if you are having a generic remap.

i could be wrong mate but this is what i understood from reading!!! [facepalm]
 

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Standard boost on mine was 10psi, but that's the 180PS engine. Runs 19psi now. Pulls 25inHg on warm idle, and less on cold start (20ish).

The N75J is just an old crummy valve that has a slow response. I'd see it as a downgrade! It allows a short boost spike as it's slower response causes the valve to close more slowly. It only gives a temporary spike, and won't hold more boost. As Chris says, the ECU decides on the boost. The N75 just switches between providing a boost feed to the vent (in the turbo intake hose) or WG actuator.

I'd say the best N75 is the latest revision from the dealer. N75's are a rip off anyway, save your cash for that K04!

IIRC the official method for inspecting peak boost is to drive along a flat road at a constant speed in 3rd gear at 2000rpm, then go wide open throttle, and the peak reading will be found between 2-3krpm. That's what the workshop manual says for my engine anyway. Hope that helps buddy [:)]
 

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Discussion Starter · #17 ·
Standard boost on mine was 10psi, but that's the 180PS engine. Runs 19psi now. Pulls 25inHg on warm idle, and less on cold start (20ish).

The N75J is just an old crummy valve that has a slow response. I'd see it as a downgrade! It allows a short boost spike as it's slower response causes the valve to close more slowly. It only gives a temporary spike, and won't hold more boost. As Chris says, the ECU decides on the boost. The N75 just switches between providing a boost feed to the vent (in the turbo intake hose) or WG actuator.

I'd say the best N75 is the latest revision from the dealer. N75's are a rip off anyway, save your cash for that K04!

IIRC the official method for inspecting peak boost is to drive along a flat road at a constant speed in 3rd gear at 2000rpm, then go wide open throttle, and the peak reading will be found between 2-3krpm. That's what the workshop manual says for my engine anyway. Hope that helps buddy
i will try it on 3rd gear to check the peak boost.

thank for the n75 info...
 
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