Hi guys, sorry about the late reply.
My R34 GTT (Garrett GT35 ) runs 18.5 psi with the standard factory boost control soloniod.( Z32 AFM).
The wastegate can is an after market unit set to 10 psi base pressure.
The control pills are selected to achieve this boost level.
The boost map in Nistune is untouched as the figures in the table do not make sense and this may or may not be a boost table(Unknown).
The TP 1 and 2 are set to 255 across the table, but this will change soon.
These were set on initial tuning because of a cut out issue later traced to an incorrect plumbing of the map sensor.
I still get an engine check light over approximately 16 PSI but have no running issues or boost cuts.
The vehicle is a daily drive car and is running 300 RWkw @ 18.5 psi and has been running this way since before Christmas.
The only modification I have made since the car first went together in October has been fitting a 0.63 Exhaust housing instead of the 1.03 fitted originally.This has made a masive power differance at 3800 RPM (87.5 kw @ the wheels).Full boost now at 3800 RPM instead of 4800 RPM.
There are still tables etc in Nistune that need identifing to enable full control but this will come in time.
Then I will remap further, but the R34 may well be a NEO 30/25 by then.
Ashley Hobson.
Classic Performance
Dyno Centre.
33 Chapman Road.
Hackham SA 5163.
Ph 08 83842899.
Mob 0409743219.
classicperform@aapt.net.au
Boost cut
Moderator: Matt
Hey guys,
Interesting thread. I recently helped with some tuning on one of these and we had no problems with boost cut. It was running a Z32 AFM, 850cc injectors and TD06 -25G turbo on 18 to 19psi. It made just under 300rwkw in it's final state of tune.
About the only weirdness was that it would show a fault code for the auto trans sometimes after a run.
It was running an aftermarket EBC so maybe that's why the factory boost sensor didn't bother it.
We'll find out more information about these shortly because Matt picked up his GT30 last night. Once that's fitted and he locates some bigger injectors it'll be on with the Z32 AFM and off to the dyno!
It'd be interesting to try mapping the factory boost control solenoid like we've managed to do on the S15. But if the boost sensor is used to monitor boost and control the solenoid then we may be in trouble.
An inline diode (NOT Zener) would probably help here as it would effectively lower the voltage from the boost sensor by 0.7V across the range. I definitely wouldn't go putting any type of diode in the AFM signal line!
Research continues...
PL
Interesting thread. I recently helped with some tuning on one of these and we had no problems with boost cut. It was running a Z32 AFM, 850cc injectors and TD06 -25G turbo on 18 to 19psi. It made just under 300rwkw in it's final state of tune.
About the only weirdness was that it would show a fault code for the auto trans sometimes after a run.
It was running an aftermarket EBC so maybe that's why the factory boost sensor didn't bother it.
We'll find out more information about these shortly because Matt picked up his GT30 last night. Once that's fitted and he locates some bigger injectors it'll be on with the Z32 AFM and off to the dyno!
It'd be interesting to try mapping the factory boost control solenoid like we've managed to do on the S15. But if the boost sensor is used to monitor boost and control the solenoid then we may be in trouble.
An inline diode (NOT Zener) would probably help here as it would effectively lower the voltage from the boost sensor by 0.7V across the range. I definitely wouldn't go putting any type of diode in the AFM signal line!
Research continues...
PL
-
chris2712au
- Posts: 343
- Joined: Thu Jun 19, 2008 1:52 am
- Location: sydney australia
looks like in that boost cut it is a map signal with 1N914 diodes (high speed..not zenner) the drop 0.7 volts a piece.. but just a theory why mess with it electronically.. put a hose and a restrictor to lower the pressure that it sees.. you can even put your boost gauge in just to make sure the map is still only seeing stock level boost signals..
