Benefits of adjusting turbo vanes?

[LBZoom]

Hey guys,
Me and some of the guys have been discussing boost related issues an the thread "ins and outs of MPG tunes" and I was wondering what the benefits of adjusting the vane position tables might be? I know I can increase boost via desired boost....so would vane position just help spool faster or what? Anyone that can offer info and help for properly adjusting these tables would be greatly appreciated. I know a couple other guys that are wondering the same thing besides myself. In the meantime I'll keep searching on dieselplace.com or maybe someone can post a link to a specific thread on there. Thanks!

[bballer182]

What happens is when you have the stock or a poorly modified (vanes not matching boost) vane table the ECM calls up the vane position for a given instance and adjust for what the table is telling it. then when the ecm realizes that the vanes position is incorrect then in has to adjust the vanes accordingly to achieve the boost requested. Mind you this all happens in the blink of an eye. so what dialing in the vane tables does, is it eliminates the ecm from having to hunt for the correct position when you don't have the tables dialed in. I have spent quite a few hours dialing them in, and it have helped the quickness of the turbo to produce the boost requested.

Within the EFI section of the diesleplace forum there are some sticky's one of which was made by nick from duramaxtuner.com and there are several video tutorials that he has made. One of which happens to be on this very subject.

[LBZoom]

I believe all of the video links are now open only to those who've purchased the tune library access...which is fine I wouldn't expect Nick to hand out his knowledge for free of course. : )

[justin123]

is there maybe a calculator for vane position like there is for timing??? if not then if it were possible maybe someone a good bit smarter than me could make one. id make one and give it out if i just knew how

[bballer182]

I would highly doubt that would be possible. Because there are way to many variables that dictate the position of the vanes to make a certain boost pressure.
IAT
main timing
pilot timing
post timing
main amount
pilot amount
post amount
RPM
altitude (barometric pressure)
mods done to the truck (exhaust, intake, down pipe, cat, muffler, egr)

There's just no way to make an accurate calculation based on all of that.

[justin123]

o well just a thought guess u cant always have it all. lol. i guess then the best way to do it would be to just adjust and log until u seem minimum movement between the programmed pos and the ecm adj. pos. thats probably gonna take a while

[bballer182]

Yes there is a certain way. and i was hoping that nick didn't delete the vids from his site but he has moved them to the payed customers section.

So... I'm assuming that you don't know how to use the MAPs within the scan tool?

Well I am self taught so I'm still learning some of the finer points haha. I never have messed with those maps within the scan tool, but after you mentioned that I went in a made a map for vane position with RPM and main fuel flow rate just like the tables in the ecm. But I'm not sure what to do with the data now that it's on the map....I did a log cruising up to 70 mph and a 0-70 takeoff.

Ah very good you figured it out! now what you need to do is drive a lot. I mean every kind of driving situation you can think of. (make sure you are at temp though) you'll make bad data! Lug it stomp on it cruise it everything. Use the map you made and copy the vane position from the map to the desired vane position map. and that's it. What i have done was once i copied the date in, i would smooth the map once or twice to fill in the cells that you didn't hit. then take it out and drive it some more and repeat the step like ten times or until you see that the new data you keep putting it is really close to what is already there.

Then BAM you just dialed in your vanes.

Make sure you have your EGR turned off and are using the EGR OFF table.

this is a hint on how to do it quickly.