Title: Not meeting req. boost on dyno Post by: Beaviz on June 20, 2014, 01:13:28 PM Had the car on a dyno the other day. Powerwise the result was fine, but the log shows me that the actual boost is far from the requested (see attached image).
Until now I have just been logging on the road and here the boost have always been spot on. I did not change much in the PID control - actually only KFLDIMX (am still running stock turbo+actuator). Unfortunately I only had one chance of logging on the dyno and did not log the N75 duty cycle. Did I miss something essential here or what am I doing wrong (attached KFLDIMX org. and mod)? Title: Re: Not meeting req. boost on dyno Post by: nyet on June 20, 2014, 03:46:20 PM 1) i would not run near the MAP limit w/o the 5120 hack.
2) post full logs Title: Re: Not meeting req. boost on dyno Post by: ddillenger on June 20, 2014, 04:11:41 PM 1) i would not run near the MAP limit w/o the 5120 hack. We've been doing this for years. I don't see the issue if it's setup properly. I still ride the map limit on a lot of cars. As for not meeting requested boost, sounds like the dyno wasn't loaded properly. Title: Re: Not meeting req. boost on dyno Post by: tjwasiak on June 20, 2014, 06:57:59 PM IMHO it is not wise idea to run on limit as you are not aware of any boost spikes which does not have to mean it is improperly tuned - hardware may fail sometime...
@Beaviz - IMHO the load on the dyno was to small but it showed your boost control is not that good as you thought it was - you should have logged N75 duty cycle and compare it with a pull on the road where you have desired boost level. Title: Re: Not meeting req. boost on dyno Post by: nyet on June 20, 2014, 08:07:56 PM We've been doing this for years. I don't see the issue if it's setup properly. I still ride the map limit on a lot of cars. agreed but there are a lot of random things to be aware of when running req literally *at* the limit... DSLOFS, I adaptation, etc. Title: Re: Not meeting req. boost on dyno Post by: Beaviz on June 21, 2014, 12:22:06 PM 1) i would not run near the MAP limit w/o the 5120 hack. 2) post full logs It is an MED9 ECU, and I have not been looking into how the 5120 hack could be applied here. I guess that it would require quite a lot of disassembling? That also means that I am limited to logging with VCDS which has a limit of 12 parameters at once. I was cheap and only got one "shot" on the dyno, so I only have one log of 12 parameters. I have attached it anyway. :) I do however have a 3bar MAP sensor added, so I can see if the actual boost spikes any higher than the original MAP sensor could measure. I can see that more of you guys are suggesting that the dyno was not loaded properly. I will ask the guy that owns the dyno how it was set up - because personally I have no idea. Maybe I should go again to get a better log since I also have to make a few other changes to the file. |