Trying to Understand BMWs VANOS for E46 M3

Hello there,

So I am used to working with non m vanos units, which go based off centerline. For example, intake cam has max retard of 126 degrees (rest) and max advance of 86 degrees. So tables have varying degrees, 117, 110, etc etc. Similar for exhaust which has max advance of -105 and max retard of -80.

I know most ecus don't function this way, they function purely on degrees advance or retard from rest (0).

If my understanding is correct, MAJORITY of the time, 0 on intake VVT system, is max retard, any number positive on that table advance the cam x degrees. While for exhaust, 0 is max advance, any positive number is retarding the cam x degrees. PLEASE CORRECT ME IF I AM WRONG.

Now, while looking at the E46 M3 Vanos tables. The mid range is 0... max retard?? shouldn't 0, max retard be in lower and higher rpm, and positive numbers, for more advance, be in the mid range? relatively speaking? I had a decent understanding before hand but I guess I have now just confused myself a bunch haha.

I will provide screenshots so you guys can have an idea of what I am talking about.

Pardon the ignorance, thank you in advance.

Positive or negative will depend entirely upon what ECU and software you are using. While you give us a lot of information, that critical piece is missing.

Sorry, I thought I mentioned it. The ECU is MSS54/MSS54HP. Currently using Renovelo ByteTuner but you can also see the same thing while using TunerPro; handled the same.

did you ever get anywhere with this? from what I understand 0 is max retard on the intake cam and any increase on those tables is advance... but yes the stock tables look a bit weird.

based on catcams sheet

catcams m3 e46 stock cams

both cams are advanced through vanos, see valve lift @ TDC

high rpm intake advance (60 is the max value) is not about tdc relative timing but for more overlap, which i think you can do it with 0 values in exhaust map and keeping the intake in retarded state (40?)

stock CSL map runs @ 50 degrees

i am afraid only way to tell is the dyno...