Boost problems?

rk696

Full Member
Aug 16, 2007
683
0
West Yorkshire
Did you put the N75 J valve in the right way round? They go the opposite way to the standard F version. It would make sense, as when it's the wrong way round, the ECU tries to close the wastegate with the n75, but because the n75 is backwards, it opens it instead, causing the turbo to cut its own boost.

However, that would normally make the turbo produce limp mode pressure which is around 600 mBar (9 PSI) iirc.
 

Pyro

Guest
6.6 psi well 6-8 normaly ;) from the logs im 99.9% sure hes got the N75 the right way round :D unless there logs before he changed it
 

rk696

Full Member
Aug 16, 2007
683
0
West Yorkshire
lol, nearly right. :D

He had the new valve when I logged it. It's strange how the boost is so consistent and doesn't vary with RPM. The turbo did sound really quiet when he gave it the beans, compared to my octy.
 
Last edited:

Pyro

Guest
lol there not i thought it was LC :doh: alan has a Ko4 that is alot quieter then my Ko3s you cant here his with the road noise :cartman:
 

JONNYVT

Full Member
Sep 9, 2002
218
5
LEICESTER
Visit site
sorry to be thick but not sure what the PFR is! I wanna fit a boost gauge (not sure which type) an need to know to which pipe i should insert the t -piece. cheers
 

JONNYVT

Full Member
Sep 9, 2002
218
5
LEICESTER
Visit site
The N75 J was installed in exactly the same position / orientation as the F valve i took out! is that wrong. Just did a few runs with the revo re-map turned off, the car is definately quicker with the map on so must be getting mre boost lower down the rev range. the new J valve def makes the turbo pick up faster but that could be downt he old one being knackered.
 

LEE69

Stage 2 Revo'd
Dec 10, 2004
21,262
74
C\UK\Devon\Torquay
sorry to be thick but not sure what the PFR is! I wanna fit a boost gauge (not sure which type) an need to know to which pipe i should insert the t -piece. cheers

DSCF1730.jpg
 
Progressive Parts, performance parts and tuning specialists