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Build Thread?


GunMetalGrey

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So from yesterdays conversation.

There are two places where intake temps can cause a lean condition which may affect your idle. It probably isnt the reason your idle is hunting but its something to be aware of

 

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^^This one mostly depends on the type of temp. sensor you have, or you can use it to manipulate the signal to make things work how you want them to while disregarding its actual purpose (a last resort on some builds where heatsoaked sensors are unavoidable)

 

 

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^^ This theoretically should stay at 100%, I have mine set to 70 and it works quite nicely. If i drove my car all 4 seasons then I would want it set to 100 but my intake temperature range only varies between 60 to 100 during the year (rather than -15 to 100)

 

 

I believe low-Z injectors are supposed to provide better idle characteristics when using large injectors. Id try refining the idle portion of the VE table a little more. 

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I will look into the MAT correction, when it revs up on idle it cuts fuel and hits a 22.4 AFR and then drops back down and does it again. 
I am running High-Z injectors now, and boy are they big.... I know the VE Table is all relevant to Req Fuel but my Req Fuel is 3.3 and my idle values in the VE table are around 30, I think I have enough overhead for more power...
I am trying to get it on the road as much as possible to get the tuning knocked out to hopefully make it to a meet! 

Side note, my stealthy-ness didn't work. The car is loud, the turbo is amazingly loud, and so is the BOV. Went past Jason's (forum browser, Dinan M5) house yesterday and let it spool up a bit, he mentioned that I could have left my intercooler black because "I'm not fooling anybody". Oh well. Always room for a muffler if I feel the need.

 

Snap: What IAT sensor are you using?

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I would strongly suggest relocating the IAT sensor. 
How you would use that table for Ideal Gas Law correction is, with a properly tuned VE table, you will log data under normal conditions and expect to see the fuel adders (gair/ gego etc) stay at or very near 100% Then while driving in a different temperature, log again (low speed, in town, hot day type driving) , if your mixture is lean  because gair is something other than 100% and all other fuel adders are at or near 100% then you would reduce the effect of the ideal gas law in the fueling equation  (drag the blue node down at the corresponding MAT) if it is for some reason richer than it should be you would drag the node up. 

 

If there is a default setting that came with the firmware I would probably leave it at that and worry more about the IAT sensor location, but if you think the sensor is in a decent location then plug away at logging until the fuel adders  until gego is at 100%.   

 

if gair is at 100% then that means the ideal gas law consideration is being ignored completely, you should only have gair at 100% near ~75F (standard temperature and pressure from chemistry class)    gair can be ___% at a different temperature, and as long as gego is 100% then you are setup right and in good hands. 

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That is all good and dandy and easy enough to mess around with but obviously my base issue is heat soak. So that being said I may investigate getting the IAT sensor into the plastic manifold (less thermal conductivity) and then create a small heat shield for the sensor. I will play with some MS settings for now to attempt to "put a band aid" on the problem. 

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I am not sure, tuning is not as easy as I thought and finding someone to drive while I tune has proven to be tricky, mix in the fact that I get high oil temps and need to get that under control makes me think that it won't be there. Which saddens me.

Edit: straight from the Holset Book of goodness. MAX oil temp under any condition: 248F or 120C
I am getting oil temps a bit past that so I don't want to risk ruining the turbo as it is oil cooled.

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  • 3 weeks later...

Alas I have retired the car for the season again, but this time in a heated shop were it is more likely that I will work on it very frequently!
The oil temp issues got the best of me and I am unable to fork over all of the cash required to put one in, along with the diff dumping a lot of oil I decided it was time again. Start build.
Took off the front again in order to start fitting the oil cooler, forgot how much I hate having hoods on when working on cars. Took that off promptly and I am always annoyed by the hood hinge being half painted and dirty underneath, so I pulled all of that out and cleaned it real nice!
IMG_20141017_175519_834_zpsf7ef906e.jpg

Much better
Started looking at the engine bay and was trying to figure out what I wanted to do with it. I have a few patches of mismatched paint from previous repair and some rust that I would like to replace by the ABS unit, luckily I can still buy the sheet metal that goes under the abs new from bmw for a price that is well worth it!
IMG_20141017_175526_397_zps42e653c1.jpg

IMG_20141017_175537_161_zps84095212.jpg

Well, might as well do my annual engine pull and do things right! 
Started prepping the motor for pulling again and decided that I will do some bay shave and tuck followed by a respray so it will actually match my exterior! I also want to paint the core support because it is not really painted and it is visible from the outside of the car. 

IMG_20141017_175618_191_zpsf8bc6e0f.jpg

The lowest cross beam in that picture, and most of the core support will be painted black.
Goals
Tuck this

IMG_20141017_175548_873_zps386010b6.jpg

Catch can this
IMG_20141017_175742_962_zps59fdf669.jpg

Delete ABS and remove lines, make a better looking and more stealth brake fluid reservoir 
IMG_20141017_175746_815_zps686a1c11.jpg

 

Also contemplating putting the fuse box in the cabin and running the engine harness straight into the firewall and not over the top of the engine.
There, major details, I want to do some small stuff as well, like add a strut bar, replace my strut tops and whatnot, but those are short little projects!

IMG_20141017_175605_227_zps74478882.jpg

Picture of half of the shop for the kids 

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