Jump to content
SAU Community

Recommended Posts

I've currently just upgraded my R34 GTR with HKS Racing Chamber Kit and HKS Racing Suction Kit. The car previously had RB25 AFM's on it and ran fine, but I was reaching the limit of them when it came to tuning. So I opted for the NISMO AFM's, believing they would be a direct replacement. Since installing the NISMO AFM's I've had no luck at all getting the car to idle (it will just stall unless some accelerator is applied) or run correctly at all. So my questions:

1. What setting in the PowerFC do I need to set my AFM's too? I've heard the VG30 works, but it doesn't work for me at all.

2. Is there different wiring from the RB25 AFM's to the NISMO AFM's?

3. Do I need the Datalogit software or similar to place the correct voltage ramp into the Powerfc for the NISMO AFM's?

4. Any other idea's at all?

Any help would be much appreciated.

Edited by Mr I Want One!
Link to comment
https://www.sau.com.au/forums/topic/274302-powerfc-with-nismo-afms-setup-help/
Share on other sites

1. For Nismo you select VG30 as they are Z32 AFM sensor in a GTR 65mm shell

2. Shouldn't be, check RB25 AFM wiring and VG30 AFM wiring, from memory its the same

3. No you don't, at least not for basic idle control and standard plodding around (ie; dont load it up on boost until you get a complete retune)

4. check ETC, SENSOR SW CHECK to make sure both AFMS show a reasonable value at idle and its consistent

1. For Nismo you select VG30 as they are Z32 AFM sensor in a GTR 65mm shell

2. Shouldn't be, check RB25 AFM wiring and VG30 AFM wiring, from memory its the same

3. No you don't, at least not for basic idle control and standard plodding around (ie; dont load it up on boost until you get a complete retune)

4. check ETC, SENSOR SW CHECK to make sure both AFMS show a reasonable value at idle and its consistent

Thanks Paul,

I've had a look at the wiring and it appears to be the same as the RB25, but if anyone knows differently please let me know. Selecting the VG30 still won't allow the car to fire up correctly, it won't run pretty much at all, if I come off the throttle it will stall instantly, when on the throttle it runs extremely rough. With it running like that it's extremely hard to get a stable value in the SENSOR SW CHECK. I'm at a loss, could it be one of the AFM's is faulty and if so whats the best way to find out which is the faulty unit?

the voltage is very low at idle with the nismo afm, had the same issue with my car when i first install them, you need a lap top with the software to start to adjust the afm voltage curve, then it will be sweet.

So I'll need the datalogit software or equivalant (what's the best one to get?)? any idea what voltage curve I should be using?

Also did your car almost completely not run at all, stall constantly, run very rough on thottle, before the voltage curve was adjusted?

Cheers for the help!

Edited by Mr I Want One!

The afm come with a voltage graph, but I forgot it when I was tuning my car on the dyno with my friend. Where are you located, most places in Australia have the software. All you need to do is set your injectors to the correct ratio in the injector settings, then i set my base fuel pressure around 5-6 psi above stock, then open up your injector map and set it to display air fuel ratio. All around idle set it to 14.7 (or near abouts) and you car wont idle it will be too lean. Just keep increasing the voltages around idle voltage until you have your desired air fuel ratio on the wide band, then continue through the rest of the map.

So I'll need the datalogit software or equivalant (what's the best one to get?)? any idea what voltage curve I should be using?

Also did your car almost completely not run at all, stall constantly, run very rough on thottle, before the voltage curve was adjusted?

Cheers for the help!

yes exactly the same, I thought there some something wrong with my car. The what I tested was I set my injector % completely wrong so that it would run extremely rich and adjusted up my fuel pressure and then it idled, then I realised it was the voltages that were not correct.

Mind you the voltages in most other areas are nearly fine.

Edited by GTR1993
The afm come with a voltage graph, but I forgot it when I was tuning my car on the dyno with my friend. Where are you located, most places in Australia have the software. All you need to do is set your injectors to the correct ratio in the injector settings, then i set my base fuel pressure around 5-6 psi above stock, then open up your injector map and set it to display air fuel ratio. All around idle set it to 14.7 (or near abouts) and you car wont idle it will be too lean. Just keep increasing the voltages around idle voltage until you have your desired air fuel ratio on the wide band, then continue through the rest of the map.

yes exactly the same, I thought there some something wrong with my car. The what I tested was I set my injector % completely wrong so that it would run extremely rich and adjusted up my fuel pressure and then it idled, then I realised it was the voltages that were not correct.

Mind you the voltages in most other areas are nearly fine.

Unfortunately I am located up in Darwin and I can't say there are many R34 GTR's running around and I doubt there are many tuning places with Powerfc software or equivalent. Which would lead me to believe I will need to purchase the Datalogit kit from NZ then head to the dyno to set it up.

you can do it with the hc. i've got the adjustment table in my gallery somwhere.

EDIT:

working_out.jpg

Fantastic! It's a bit late to try them tonight, but I'll give those values a go tomorrow! Thanks a lot for your help!

I'll let you know how I faired.

Thanks to everyone for your help so far!

I would have to go back through it, but that table is different to the graph, when i was adjusting it both those tables were there, but the afm graph one has a heap more points in it. the other one is a correction to the graph, not sure what the actual difference would be in how the car would run though.

  • 5 months later...
Unfortunately I am located up in Darwin and I can't say there are many R34 GTR's running around and I doubt there are many tuning places with Powerfc software or equivalent. Which would lead me to believe I will need to purchase the Datalogit kit from NZ then head to the dyno to set it up.

Cant say fer sure bout the others but HiTech Tuning Definitley have datalogit and experience tuning powerfc

Pretty sure you will find most do even in Darwin!!!!!!!!!!!!

Hey mate, I'm in Darwin also and I've got an R34 GTR too. I just put z32's about two weeks ago and had a lot of problems getting them to work. "noone" is right, take it to Dave at HiTech, he's got the datalogic software so you don't have to purchase it as well as experience building and tuning RB26's. Good Luck mate, by the way what colour is your beast???

Edited by full_stick

Thanks for everyones help. I finally got them fitted and tuned by Dave, it did require the datalogit software to make them work correctly. Car runs perfectly now.

full_stick - it's the silver vspec II with R34 GTR plates.

  • 11 months later...
Thats a interesting way of doing it :blink:

Bumping an old thread here but care to elaborate on this comment?

Is it because the Z32 values should be entered as they are the same internally?

EDIT : Just tried mine, set to VG30 all voltages standard @ 100% starts and dies, changed the first 2 voltage settings and it ran for a bit longer but died again, guessing if i change them all it'll run....

But - i'm now wondering where these extra values added on that chart sav man put up - are they the percentages (or are they only able to be entered with a datalogit)

Edited by endless
Bumping an old thread here but care to elaborate on this comment?

Is it because the Z32 values should be entered as they are the same internally?

EDIT : Just tried mine, set to VG30 all voltages standard @ 100% starts and dies, changed the first 2 voltage settings and it ran for a bit longer but died again, guessing if i change them all it'll run....

But - i'm now wondering where these extra values added on that chart sav man put up - are they the percentages (or are they only able to be entered with a datalogit)

best bet is to use a calibrated voltage curve and leave those % all @ 100%. I really dont like seeing adjustments over 2-3% in those compensation tables...

if you send me a pm i will remember to post up a properly calibrated nismo AFm curve

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

    • Please ignore I found the right way of installing it thanks
    • There are advantages, and disadvantages to remapping the factory.   The factory runs billions of different maps, to account for sooooo many variables, especially when you bring in things like constantly variable cams etc. By remapping all those maps appropriately, you can get the car to drive so damn nicely, and very much so like it does from the factory. This means it can utilise a LOT of weird things in the maps, to alter how it drives in situations like cruise on a freeway, and how that will get your fuel economy right down.   I haven't seen an aftermarket ECU that truly has THAT MANY adjustable parameters. EG, the VAG ECUs are somewhere around 2,000 different tables for it to work out what to do at any one point in time. So for a vehicle being daily driven etc, I see this as a great advantage, but it does mean spending a bit more time, and with a tuner who really knows that ECU.   On the flip side, an aftermarket ECU, in something like a weekender, or a proper race car, torque based tuning IMO doesn't make that much sense. In those scenarios you're not out there hunting down stuff like "the best way to minimise fuel usage at minor power so that we can go from 8L/100km to 7.3L/100km. You're more worried about it being ready to make as much freaking power as possible when you step back on the loud pedal as you come out of turn 2, not waiting the extra 100ms for all the cams to adjust etc. So in this scenario, realistically you tune the motor to make power, based on the load. People will then play with things like throttle response, and drive by wire mapping to get it more "driveable".   Funnily enough, I was watching something Finnegans Garage, and he has a huge blown Hemi in a 9 second 1955 Chev that is road registered. To make it more driveable on the road recently, they started testing blocking up the intake with kids footballs, to effectively reduce air flow when they're on the road, and make the throttle less touchy and more driveable. Plus some other weird shit the yankee aftermarket ECUs do. Made me think of Kinks R34...
    • I do this, I also don't get the joke  
    • Return flow cooler will be killing you I reckon. You can certainly push more through a low mount setup but they're good numbers for a stock looking engine bay.  Mine made 345rwkw (hub) at 22psi on 98 with a "highflow" on a stock manifold but it's a long way from a normal high flow or standard engine. I used one of those Turbosmart IWG-75's and it was great with the Motec running closed loop boost with pressure being applied to both sides of the diaphragm. 
    • Hey man do you have pic of adaptor plate by any chance I need to match up the bolt holes as my gearbox adaptor plate ones are way off the only bolts of starter motor are matching thanks 
×
×
  • Create New...