Jump to content
SAU Community

Recommended Posts

Hi folks,

everyone Tuning and upgrading a Neo engine will run into this problem sooner or later.

The Boost sensor on the neo cuts fuel if sees lots of boost around 14 PSI.

Now as some people say the sensor is not only a failsafe, rather then also helping under vacuum setting fueling.

so to get around that Problem I will try to install a checkvalve infront of it. So under boost no pressure will arrive the sensor but it can see vacuum.

 

Has anyone tried that before?

 

I am Running 

FMIC

new Coilpacks

 A Gt3071r turbo

custom exhaust 

oilcooler and Catchcan setup

 

to install now is R35 injectors and R35 AFM

will then be tuned with nistune.

 

Off Topic:

At 250 km/h on the Autobahn B—Pillar Driverside left the Game and is not seen jet.

Does anyone know where to get one.

Link to comment
https://www.sau.com.au/forums/topic/480844-boost-sensor-mapsensor-neo-engine/
Share on other sites

Easiest place to get one would be beside the autobahn probably....the front inner guard liners are also poorly attached for high speed so watch out for a massive noise followed by no braking on one side after the guard liner slides under the whell....

Re the ECU Boost cut, even before you hit that you will be in parts of the stock may with retarded timing and rich AFRs, designed by the factory to protect when you are outside "normal" parameters as you are at 14psi

Just do the Nistune first and fix those areas of the map, someone else can confirm but I expect it can remove the boost cut too. No need to add a checkvalve.

  • Like 1
1 minute ago, GTSBoy said:

Boost sensor can be dealt with in Nistune.

Max out the boost cut to 255, however leave it connected, as soon as you disconnect it Nistune goes crazy and always references the last column on boost.

Initial Nistune documentation said it could be disconnected and disabled however subsequent guides recommend it be connected, hooked up however disabled in the software. If not it will be an absolute pig to drive, it keeps referencing the last column on transient throttle.

According to the Nistune Neo tuning guide you can increase boost to 18 psi by increasing the  boost sensor fuel cut table to a maximum of 5100 millivolts. Is it possible to change the factory sensor for a 3 bar map sensor and then tune  to increase boost to 30 psi?

I think the best way to deal with the boost sensor's inherent upper limit would be to treat it like a wastegate and put a bleed valve on it. You put a restriction between the plenum source and the sensor, and bleed some boost out of the sense line between that restriction and the sensor. Just like a wastegate, the sensor will see a lower boost than the engine does. If you need to run 25 psi, you just bleed that down to <18 psi and it will still do what it is supposed to do.

Can’t see a bleedvalve work in that area, pressure will rise or a boostleak will be build in your application. 

 

@Duncan as soon as i saw prices on those parts i should have looked for it no matter what

Yes, even running a piggy and altering AFM Volts to reach sufficiant fueling , the car retards timing down to 3 degrees at 5 psi. Reason being i have to show him more Airflow in areas of the map where it shouldnt , to keep AFR around 12.

@NZ-GTT -i think all sensors work the same it lol give different output, based on how much the ECU works with the input it might might not work.

 

All in All, u cant get away with a piggy, after modding intake to turbo to exhaust hoping it lol run fine.

Boost sensors have a linear output of 0-5V relative to whatever the input pressure range of the sensor is. So if the factory sensor that appears to be a 2 bar map sensor was changed out to a 3 bar, the output voltage to the ecu remains at 0-5V but with a larger pressure range.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Nice one, I'd argue that the white S1 RS260 is certainly the best looking of the Stageas. And yes, fully agree on the forum situation. It's a bit of a shame, but at least SAU is a good place to be. I found the facebook groups to give me FOMO because people were trying to one-up each other and show off in some way. Feels much more natural here. There are people with seriously nice builds, but I can appreciate it rather than it making me question my life choices. Might be that people are more open with sharing how much work/money/suffering it takes to actually get there. 
    • Evening, wanted to pop in and finally register to say hi to everyone here on SAU!   It's been a while since I've been active on a forum, but back in the day I used to be relatively active on ClubLexus and other hobby-related forums. I'm glad to see SAU is still around, since with the advent of Facebook and Discord it seems forums aren't what they once were. As a recent new owner of an S1 260RS Stagea, I've found so many older guides and helpful tips from SAU that I figured I needed to join and say a grave thank you. My recent acquisition has only become legal in the US for the past year, and knowing that similar car enthusiasts from across the pond have already figured out the kinks and tricks to get these 25+ year old cars running well. I look forward to diving into more of the SAU forums as well as hopefully contribute some info myself for future posterity.   As a pic tax, here is one of the few good photos I have of my Stagea. I hope to get way more in the future!    
    • Is this where I say "Hey man my airbox cost me horsepower in my Naturally Aspirated Engine"? (I know you need them for legality in NSW)
    • 1.5mm alloy folded up, it will need a tweek, as the angled bend only got to around 45° as that was the max that the break press would get with the other bends, and I needed a fair bit more, but and the alloy is easy to bend too my will by hand once I trim the lower section out I'll Dremel out and form the angle and mounting point on the lower section when time permits  As for the lid, I'm looking at going a "cap", instead of a flat lid to hide the fixtures a bit
×
×
  • Create New...