NefMoto

Hi Guys.  I'm hoping a few veterans might be willing to share their best known strategy for dialing in injectors.

I've been attempting to dial in a set of ev14 550s on my 1.8t.  It's all factory hardware, OEM fuel pump maf wideband etc.  I used the manufacturers TVUB specs from the EV14 migration thread and calculated a theoretical KRKTE value from masterj's excel wizard as a jumping off point.  I also set FKKVS and KFKHFM to all 1's.

No idle or drive-ability issues but the trims suggest a rich condition at idle and partial, but WOT suggests a slightly lean condition.

My gut says I should tune KRKTE to iron out the trims and then tune KFKHFM to iron out WOT but I don't know if that's an ideal approach considering I'm around -18% LTFT.  I'm not fond of the idea of swaying from the manufacturers latency specs but I'm not closed off to the idea either, more-so just leery on how to go about making adjustments.  I'm not looking for hand holding, but a couple jumping off points would be appreciated. 

Thanks!

Use guitar24t's FKKVS fixer to fix the non linearity of the injectors :)

http://nefariousmotorsports.com/forum/index.php?topic=6005.0

I was under the impression that I should be more dialed in before using the fixer but I'm certainly open to it.

Drop the krkte number down until you get ltft closer to zero, then do the fkkvs fixer if you need it.

If it's factory hardware then I would just use the Tvub from the manufacture and KRKTE to 0.55. leave the FKKVS and KFKHFM as stock and go from there, if your trims are going out then just adjust the KRKTE until you get to around 3-5% and then should be more than fine for pretty much anything you throw at a set of 550's. No real need to start messing with the other maps imho .

My strategy was to use a calculated KRKTE that matched the flow of the injectors, injector specific TVUB

Then I set FKKVS to all 1's and ran the fixer on 3 consecutive 30 min logs and my LTFT are 0 now STFT vary 5% at either side of 0 when I give it a hard time :)

I'm not saying what I did is the best/correct way, but it worked great for me :)

Best way, get your injectors flow tested before fitting and don't assume they flow 550cc

Absolutely, or buy flow matched injectors with data sheets :)

There's a reason why I said what I said... and once Gin+  has results if he/she engages his/hers brain they will be able to change just krkte and have ltft around -3%

Thanks for the replies!

Turns out LTFT trim is fine now that I learned that the factory fuel pressure is 4 bar instead of 3.  Set KFKHFM back to stock.  I'll log for the FKVVS fixer when I get a chance.