S14 K Const too high?

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apex128
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Joined: Mon May 08, 2017 11:26 am

S14 K Const too high?

Postby apex128 » Mon Jun 12, 2017 1:58 pm

Hello everyone,

I have an issue with tuning my s14. I set the kconst to be stoich of cruise and idle, but when I go in boost its too rich. I emailed Matt about this before my forum account had a chance to be activated, and he told me to fix my load scalers. I now have, and the issue is better, but still occurs. If I try to manually take away fuel on the fuel map, the calculated afr value is in the 12s, but the real afr is 10. I will upload my logs and tune for you guys to look at. Any idea why this is happening?

Thanks

apex128
Posts: 5
Joined: Mon May 08, 2017 11:26 am

Re: S14 K Const too high?

Postby apex128 » Mon Jun 12, 2017 2:07 pm


Matt
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Re: S14 K Const too high?

Postby Matt » Tue Jun 13, 2017 1:52 pm

It is 'estimated AFR' not 'calculated AFR' which is only good for factory setup (injectors)

Once you change injectors or MAF then everything changes... why I want to remove this view from the software because it gets confused too often (but some tuners use it for VQ tuning, so only available in expert view)

ECU only works from pulsewidth, so work with fuel map 'filtered view' instead of 'estimated AFR' view and use your wideband only to determine AFRs for tuning. Flatten the fuel map futher until you get the AFRs you need (ie not in the 10s')

apex128
Posts: 5
Joined: Mon May 08, 2017 11:26 am

Re: S14 K Const too high?

Postby apex128 » Wed Jun 14, 2017 12:47 pm

The thing is that I have lowered the values on the fuel map, but nothing seems to affect the afr when in boost after ~4000 rpm. I had the fuel map raw values at 2 and it was still going < 10 afr :x . Starting to think maybe this isn't a tuning issue... I'm not saying it isn't a tuning issue, but I am definitely beginning to have doubts. Could it be a bad maf or tps? Could it be bad injectors? They seem to work fine for idle and cruise, so idk whats going on here.

Matt
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Re: S14 K Const too high?

Postby Matt » Wed Jun 14, 2017 10:40 pm

Please confirm email address for licence and I can look into it futher

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Re: S14 K Const too high?

Postby Matt » Fri Jun 16, 2017 11:14 am

Thanks for the good logs with AFRs included. I've played back one of the logs today. Also tuning adjustments look good.

What injector size and brand injectors?

At this point since the K constant is almost doubled (from 257 to 467) this doubles the TP (and resulting injection time) which can only be alleviated by dropping the fuel map further

Playback shows going from 11.18 AFR (at 13.64ms) to pegging the wideband at 10:1 AFR at the top end of the map (ECU commanding injection time 14.85 - 20.92ms effectively flooding it)

I would think around 14.85ms injection time should be held through the rest of the map (fuel map values around 17 for the top end of the fuel map - so make the top corner 17's in the fuel map). Set this value, then do another run and see if the injection time stays around 14.85 (as TP rises injection time will also increase, however). After doing the run post the log (or similar screenshot would be easier) to view

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Re: S14 K Const too high?

Postby Matt » Fri Jun 16, 2017 11:15 am

pic

apex128
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Re: S14 K Const too high?

Postby apex128 » Fri Jun 16, 2017 4:07 pm

I'm running 370cc Deatschwerks fuel injectors. I will try reducing those fuel map values tomorrow. I had them set much lower than 17 in the past however, and it was still going rich. I'll let you know how it goes and post up a log.

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Re: S14 K Const too high?

Postby Matt » Mon Jun 19, 2017 9:42 am

Deutchworks = drilled out OEM injectors

Okay we will see if you get a drop in AFRs when your injection time is lowered

apex128
Posts: 5
Joined: Mon May 08, 2017 11:26 am

Re: S14 K Const too high?

Postby apex128 » Thu Jun 22, 2017 12:41 am

Unfortunately the other day I found a fairly large vacuum leak / boost leak. Might take me a while to fix it, but after it's done I can start playing with the map again.


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