Tune after Upgrading afm and injectors

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kostjazz
Posts: 6
Joined: Fri Feb 01, 2013 7:51 pm

Tune after Upgrading afm and injectors

Post by kostjazz » Tue Jun 18, 2019 9:59 pm

Hi guys,

I realise its a noob question, but I think I read every doc on the net multiple times and still cannot figure out whats going on.

I have S15 with feature pack ecu.

Recently Ive upgraded AFM to Z32 and stock 480cc injectors to 1000cc Xspurt.

As for the tuning I went and resized AFM and Injectors, then adjusted TIM at 2000 RPM to achieve ~0 trims then adjusted Injectors latency and and K value to make sure I'm using the whole map.

Now the issue Im having is that under load it's running super rich(AFR is around 9), while filtered values in last columns are 10. And that's on the same boost of around 1 bar.

Before injectors/Maf change AFRs were 11.5 and values in last 2 columns were 31.

Now I knew that fuel map was going to get flatter, but that much?

That doesn't seem to leave much for adjustment. Is there anything else I can look into?
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Screen Shot 2019-06-18 at 8.55.14 pm.png (472.29 KiB) Viewed 223 times

Matt
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Re: Tune after Upgrading afm and injectors

Post by Matt » Wed Jun 19, 2019 12:36 pm

Sounds like base fueling wasn't setup properly after adjusting K for load

If you lifted the whole map up +13 to get rid of the negative values, and then readjusted TIM (removing fuel) your top end would then be 23 values

Yes 1000CC result in quite a flat fuel map, since there is less trimming of base fuel values (calculated from MAF) required)

That big spike around idle should be rectified with fixing up latency (about 1150us for 1000CC)

kostjazz
Posts: 6
Joined: Fri Feb 01, 2013 7:51 pm

Re: Tune after Upgrading afm and injectors

Post by kostjazz » Wed Jun 19, 2019 1:21 pm

Cool thanks for the prompt answer.

I wonder why reputable tuner went negative originally. It's not a common practice isn't it?

Matt
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Re: Tune after Upgrading afm and injectors

Post by Matt » Wed Jun 26, 2019 10:37 am

not normally, but tuners go between so many different tuning packages that they just try to get the job done

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