Need help with MAF upgrade

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CHIEFAPONTE
 

Posts: 23
Joined: Tue Nov 10, 2015 5:13 pm
Location: Sasebo, Japan

Need help with MAF upgrade

Post by CHIEFAPONTE »

I recently upgraded my injectors to HKS 600 cc injectors and a set of z32 MAFs.

My car is a 1991 R32 GTR. with the following mods

R34 N1 turboes
pomcams 260 cams
catless 3 inch exhaust
NISTUNE FP ECU

on the injector install, I followed the menu on the nistune software to include the adjustment on the cranking tables, max load limit and TIM. After the injector resize the car ran well. minor adjustments to TIM got the AFRs very close to the target.

The problem I have is with the MAF resize. Once the Z32 MAFs are installed and I go through the change MAF utility on NISTUNE, the car would not start. I then changed the values on the "MAF VOLTAGE QUANTIFIER [RAW]" to reflect the same values of the stock R32 MAFs and the car ran fairly well but rich.

I then adjusted Kconstant down and TIM up(see attached BIN) and the car misses just a bit on initial acceleration, but I am concerned that my adjustments of K and TIM may be too much.

Can anyone look at the attached file and give me some advise?
what do you think about me having to replace the MAF VOLTAGE QUANTIFIER [RAW] values for the original values?
Attachments
1991 bnr32 600cc hks inj z32 maf.bin
(32 KiB) Downloaded 104 times
Last edited by CHIEFAPONTE on Thu Jan 05, 2017 2:43 pm, edited 1 time in total.
CHIEFAPONTE
 

Posts: 23
Joined: Tue Nov 10, 2015 5:13 pm
Location: Sasebo, Japan

Re: Need help with MAF upgrade

Post by CHIEFAPONTE »

Update. I decided to use the vq transfer generator and using the data for the hpx n1 maf and scaled to 33% i got the car running and accelerating well. The only issue is that the AFRs are a bit rich.
Matt
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Re: Need help with MAF upgrade

Post by Matt »

Make sure the 'R32 GTR' MAF tickbox is selected when doing the MAF resize (adjusts the K constant differently)


The K constant needs to be adjusted with twin MAFs when doing this resize. What you can do is resize again to the Z32 MAFs and then adjust the K constant afterwards until car starts and runs again

If you have feature pack, adjust K constant until load reaches the end of the fuel map (adjust the Total Injection multiplier) to adjust your fueling to be back to normal
CHIEFAPONTE
 

Posts: 23
Joined: Tue Nov 10, 2015 5:13 pm
Location: Sasebo, Japan

Re: Need help with MAF upgrade

Post by CHIEFAPONTE »

Thanks Matt. I do have a FP board.

what does it mean when you say "adjust until it reaches the end of the fuel map"?

Should I adjust only TIM? Or K constant only? should I tick the "auto TIM" as I adjust Kcont?

how much of a split on my MAFs is too much? my logs show an average of .2 to .5 volts

please explain and thanks a gain for your patience and help
Attachments
600cc inj stock maf 20dec16_3.csv
(185.12 KiB) Downloaded 95 times
CHIEFAPONTE
 

Posts: 23
Joined: Tue Nov 10, 2015 5:13 pm
Location: Sasebo, Japan

Re: Need help with MAF upgrade(PROBLEM SOLVED)

Post by CHIEFAPONTE »

Matt. my MAF resize issue has been resolved. I believe the issue with my maf resize was that the option named "Z32 VG30DETT (GTR ECU)" was bad. I re-did the procress using the option named "Z32 VG30DETT" which worked fine.

attached is my bin file.

Thanks for the help
Attachments
1991 BNR32 GOOD TUNE MODIFIED FOR Z32 MAFS 05JAN17 600 CC INJ.bin
(32 KiB) Downloaded 119 times
Matt
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Re: Need help with MAF upgrade

Post by Matt »

That item is only so that after doing resize it will show as Z32 VG30DETT (GTR) ... perhaps I should remove it since it is causing confusion. Instead it will show as 'unknown' however
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