NefMoto

I have a noob question about controling my boost..

On my old 1.8T i have been running an MBC for years and I want to try control my boost via PWM valve instead. I could not find my old N75 in my garage but i found another type of valve that might work.. Its a bleed valve (Pierburg). It has no vent out.  It suits me because i the just replace my MBC with this.

As I understand Me7 controls boost after desired LOAD and then follows Maximum LOAD (LDRXN). But is there not a map where i can just tune Duty Cycle? Or is Duty cycle calculated to give the desired load that is requested

Here a pic on my valve..

LDRPID is what you want to look into, it has a duty cycle feed forward and all the other related maps :)

Just get an N75.

Boost control is described at length on the s4wiki tuning page and all over the place on this very site. I have no idea why you apparently have STILL not read any of it.

Exactly.  Why dick around with anything else?

I mean, if he had ANY understanding of the PID i'd say, sure, go for it, experiment given what you know about boost control. But he hasn't even bothered to try to do any learning whatsoever.

LoL i Work with PID loops every day. Or do you mean Me7 PIDs are diffrent?  I have read the Wiki and as i understand that the PWM signal is feed or adjusted by the P.I.D.  It would be nice though if I just had a Map with duty cycle RPM vs PEDAL position..

My question was can i use this type of valve..  Im just curious how i could use a valve like this. Would it be possible to control it in open loop.. It would be dangerous in certain cases but anyway.

I guess i have to try and error this time aswell.. or get an N75

Simple answer is you can set CWMDAPP to 8 and then KFLDRAPP will be your duty cycle table.

I'm not sure of any effects on the torque model or anything else, I'm just aware it can be done, if I were you I'd research it before using it. There's plenty of info. about it on here.

Edited: Incorrect codeword bit set and duty cycle map name.

My TQ monitoring is disabled.. dont know if that simplify things..

Ok that sounds interesting.. now i have something to search for.

I read that Setting that CWMDAPP to = 1 and then use KFLDRAPP as duty cycle. But u say KFLDRL.

My apologies! KFLDRAPP is correct (I was on a call at work not concentrating properly).

Edited to correct.

Should be 8, not 1.

I was confused.  Thanks..

Are you just bored and you want to tinker around with something?  ??? Because on me7.5 there is already a perfectly fine method of operations to get desired boost dialed in without the need for switching valves and tinkering with an MBC and whatnot... Its all in the maps. LDRXN, KFLDIMX, KFLDRL... Get your load request dialed in then move onto PID. It takes a lot of trial and error but eventually you will find your sweet spot, given your adjusting appropriate maps in a proper fashion.

Experimenting alot with my Me7 cars.. Some ppl might consider that boring i don know.... :)

Not at all, but you're re-inventing the wheel using 2x4's.

If we all thought it was boring me7 wouldnt exist. lol :D

so rock on! boost high and prosper!