Evo8RLK

iTrader: (1)

Well friends.. I have a bit of a probem.. as the title says i finally got the urge to try out the ecu controlled boost with the grimmspeed solenoid. I followed all the instructions and got all the tables pretty well figured out and now just started to get my boost curve dialed in at 22 psi.

On the first drive when i start to log from 2000 rpm to 7000 rpm, I am pretty sure Im getting compressor surge at WOT between 3500 to 4200 rpm ish constant and then it is perfectly fine througout the rest of the rpm range. I tried to dial back the boost in that rpm range because of the thought of the engine couldn't handle that much pressure.. and it sounds like it doesnt surge as much but its still there.. driving normaly as in if i start out in first and mash it and i go through the gears it doesn't surge once.

Im sure you have all heard this many of times and i've been sick of reading about alot of threads about compressor surges but i couldnt find the answer that i am looking for.

What makes most sense for me is that the problem would lie in getting the boost tuned correctly. If so does anyone have any tips to get rid of the surge? Or at least to set me on the right path on to getting this new set up tuned correctly. Thanks in advance!

bassnuker

iTrader: (14)

I have an 06 MR with the Grimmspeed and I was having the same issue, especially in 5th and 6th gears. I would be on the freeway and give it a little gas and let off and the car would shudder. I still use the Grimmspeed but did get a new tune, along with a new turbo, manifold, O2 housing, and intercooler and no longer have the surge. I am pretty sure the tune was what fixed the problem but it could have been the turbo. My old turbo had over 160k miles on it and it had never been rebuilt.

Evo8RLK

iTrader: (1)

Well when you let off that probably has to do with bov and somewhat with the wastegate. I did some more reading and most likely the flutter is caused by the wastegate. With it opening and closing rapidly at that rpm range (which could the ecu be bleeding off the boost to prevent it from overboosting?). This only happened when I changed to the grimmspeed. My aem truboost never had this problem so I come to believe that this problem lies in the tuning of the grimmspeed. which I looked the other day and I was totally off on some tables. I had my atmosphereic pressure number way lower than it should have been. I changed them now so all I have to do is flash it and see what happens. I'll keep you posted.

Evo8RLK

iTrader: (1)

I changed the settings but nothing really changed as much as I had hoped. I guess ill tune it to get the boost dead on and then ill go from there with the flutter.