Hi guys, I have a problem with the tune from the AP (from Stage 1 FMIC to Stage 3, running stock there is no problem). Already sent Chris an email with the problem and the log, but maybe someone here already had this problem and found a solution.

Here is a video with the problem, from second 6 to 8, you can hear the diverter valve dumping air, engine from 2,500/3000 rpm to 4,000/4,500 rpm, past that rpm everything is normal. I have this problem 95% of the times, with all gears (haven't tryed in 5 or 6). Not sure if it's normal behavior, but when I don't have the problem the car pull harder.

Video:



Mods in the car Alta FMIC, Alta AP, Alta Spring, Alta Turboback 3" & downpipe and Alta CAI.

 

Hard to tell from the video but did you let off the throttle once it occurred or was that just the loss of boost?

 

Yes video is very bad, will try to get a good camera to record it better. I hit the throttle from second 4 to 15, done in fourth gear.

 

Could be overboosting. Try doing a run and watching the boost pressure. If it goes past 20# or so the ECU will automatically dump boost.

 

Did some runs but on the AP display it looked ok. Here is part of the log, I added some red color in 2,500 rpm to 4,000 rpm. For me looks good, but I'm not an expert, it's my first car with turbo, so my knowledge is zero

http://s14.postimage.org/olpytrtht/bost.jpg

 

Looks like that is what's happening, but I'm no expert. The only reason I bring this up is because the same thing happened to me, and that's what it was. Also, again I'm no expert, it could be your diverter valve. We'll see if someone else chimes in.

 

1400 mBar is about 20 psi correct? I'm no mathematician and if I'm getting this wrong PLEASE say so but MINI cuts boost at 20 psi until it drops to 5psi if I remember right. If the conversion is right it looks like your car is beginning to cut boost at a little after where you've highlighted in red. So at about 2600-2700 rpm it's hitting 20 psi. I think the highest reading on that graph is approximately 22 psi keeping in mind it was logged in mBars. Again I could be way off on all this.

 

Well what is an owner of a 2012 MCS to do? Seems the manufacturer has encoded the ECU to prevent after market modifications? Can I just switch back to a 2010 ECU? pros and cons

Or does your company have a different solution on the horizon?

 

 

It even hits 1600 mbar = 23 psi at 4,663 rpm. By the way, it's the JCW, not sure if that model it's allowed to cut the boost past the 20 psi.

 

As far as I know JCW or MCS, they'll both cut boost at 20 psi.

 

Andres,

Sorry it's taking a while, I'm going to have Jeff check it out and get back to you really soon.

 

No problem Chris, this is the actual anwser from Jeff in case someone in the future have this behavior:

 

Surging. The JCW does not have a 20 psi boost cut.

 

So does it cut boost at all? I could've sworn I've read more than one thread discussing boost cuts involving JCW's at or at least close to 20 psi

 

Data log shows up to 1600 mbar = 23 psi in Stage 1 FMIC or Stage 3, so definitely JCW doesn't cut at 20 psi.

 

I experienced the fluttering too when i installed the stage 1 and was pushing higher rpms. I forgot to post on here, but this is good to know.

Happy T-giving

Sent from my DROID BIONIC using NAMotoring

 

I must be seeing this too then. I was thinking it was related to cuts since I hadn't experienced either in a car before and from reading threads on the issue its all I could see as the possible issue.

It's hard to hear on the video (for me) but when this happens does it feel like the turbo bogs down a bit without totally giving up boost? It's hard to explain the accompanying sound but the best I can describe it is going from a high tone of boost building to a sort of flatlining whirring sound.

 

Just got my AP installed, noticed something pretty quickly..

During shifts, the engine seems to hold revs for a second, or.. even over rev during the shift.

I had one instance where I shifted at 6000rpm, but the tach jumped to 6500 before coming down.

Anyone else experience this?

 

No I've not seen this with my car.

 

Mine does this intermittently. High vacuum decel shifts too.

 

It doesnt seem right. If I was actually shifting hard/fast, I would totally be engaging the clutch before the revs fall again. Its a very slow process/

 

fast shifting hasnt yielded the issue before

 

I did a quick run last night to see if I had that issue, but nothing.

Sent from my DROID BIONIC using NAMotoring

 

I took some datalogs today, pretty obvious, here are some graphs of Throttle position and RPM. Why is RPM spiking after lifting?