Advanced Tuning Discussion - Vanos

[Brakbro]

I've been tuning for a small amount of time 700 ish revisions on my own car as I continue to learn and I'm ready to step into tuning my VANOS which is a set of tables I've never really needed to touch to get results. However, I know that there are benefits to tuning VANOS, I found this old thread for N54 https://www.spoolstreet.com/threads/vanos-tuning.2189/ .

To increase spool do I increase or decrease the intake table by 5% and what is the VANOS table limit before I start doing harm? I read that I can adjust the exhaust VANOS to deal with some timing corrections as well but that is in a post for the N54 and I just wanted to make sure it was applicable to the B58.

Finally the valve overlap table X axis is confusing, why does it only go to 260rpm.... I don't plan to touch that table unless I get advice otherwise. Thanks in advance to anyone who replies!

-Brakbro

 

[Klos]

Sorry just out of curiosity what software is that?

 

[Brakbro]

Sorry just out of curiosity what software is that?

Bootmod3

 

[Klos]

Bootmod3

Where can you download it? Looks much nicer than Tuner Pro RT

 

[135boost]

Hello again, been "sleeping"all long winter and got first road tests done yesterday with my 135.
to topic.

it seems to be some kind of dark matter level of wichcraft tuning these vanos things so i did some amount of
background digging on these on multiple platforms snd forums.

without copying anything and believing it`s holy grail thing, from small twins with quite much backpressure to big g40 1150 these all has some main basic principles on tuning intake and exhaust vanos.

on idle, smooth idle is arcieved with very much cam separation, eg. intake degreed at some 125 and exhaust at some 130, that is good starting point to all these.

Then it`s little to do with how much you guys want egr effect, on light load you can go to quite much overlap, eg 75-80 degree on intake and 80-85 on exhaust, that is more to do with fuel saving than performance but then come the important part of vanos tuning.

wot from 2500 all way up to redline you can log those cells where it touch, on small twins, it goes trough map to that right side to 160-240 loads in very low rpm`s, prox 2000-2500 and on huge turbos (like mine) it goes trough map at wot on prox 120 at 3000, 150 at 4000, 200 at 5000 and so on ( rescaled load and rpm) but at wot uou should target intake and exhaust cam to follow your boost curve.

idea is something like this

if boost start to build at wot from 2500, and full boost at 4500, start with some 80 degree intake cam timing at 2500 and 108 at 4500 and exhaust cam from 85 at 2500 and 108 at 4000, then follow those close to max hp rpm.

after max hp rpm if you have stock awful flowing head, or turbos with much back pressure, you have to compensate those with cam timing pulling intake cam timing even more to 116-120 levels and exhaust to 112 levels.

there is logic behind cam timing, not just "copy these values" and it work.

those vanos timing is follow powerband and boost curve at most with intake following some 3-400 rpm behind exhaust until max boost setting is reached.

^^^^^^^^^^
disclaimer, this is not including any scientific exact values, you have to test and tune your own vanos timing with your setup, this was just
to get some idea what you are lucking for and to eyeopening heireka moment why copying vanos maps from different setups is not
working so well.

^^^^^^^^^


sorry, it`s not so easy to explain but just figure out that from example there.
that same fundamental rules goes trough all other platforms too with deviation caused from
better or worse head flow, bigger or smaller turbos with different back pressures etc

https://www.jb4tech.com/forum/model-specific-engine-tuning-modification-discussion/n54/7618-