Hello everyone!

After installing a MAP UICP and grimmspeed 3-port, I noticed that when under load there is a fluttering sound. The fluttering spool occurs in 3rd and 4th gear, and above 3k rpms. The fluttering occurs when 50% throttle is applied. The spool sounds normal in the beginning, but after ~16psi is when the fluttering occurs. The sound only occurs when I am on the throttle.

The fluttering doesn't seem to be affecting performance. There is no compression surge, and my max boost is around 23-24psi.

I thought it was the UICP leaking. I re-tightened everything, but the fluttering is still there. I have done some research, and it seem like wastegate fluttering is commonly heard with 3-ports.

Here are my current mods:
2012 EVO X GSR
HFC
Catback exhaust
Cobb SF intake w/ Perrin turbo inlet
UICP
3-Port
Cobb AP w/ 93oct stage 2 SF + CBCS

Before anyone says anything about not being tuned, I am running a Cobb OTS map that supports the Cobb 3-port. The grimmspeed 3-port is the same as the cobb's 3-port. Of course the OTS maps are not as good as custom tunes, but the OTS maps are all I have right now. A pro-tune will come later on, so please do not just say "get a pro-tune."

I have attached a log and virtual dyno results.

I just wanted to make sure that what I am hearing is normal, and the wastegate fluttering doesn't harm my turbo or engine? I do not mind the sound, but it just sounds really...intense haha.

Thanks!

 

I had a similar thing happen and I have similar mods.
AMS intake, UICP, IC, Cobb TBE, 3 port and custom tune with AP.

 

Your boost curve looks aiiight, nothing terrible or catastrophic.. Just by glancing your VD plot.. Probably just need to adjust the WGDC % tables, aka you're going to need a tune for the best results. The OTS tunes doesn't react well to a mix / match of parts, as I'm sure you know. Regardless if the parts are "similar" in design, they may perform completely different.

I wish I could see your log file.. I could of helped more. Be sure the knock is within reasonable levels. If there's a lot of knock activity, turn the boost down.

 

If you hear it at the top of the pull thats the turbo running out of puff I'm on HKS panel, GS 3port, upper hard pipe, 3in single catback, and tune at 23psi 337HP/349TQ and I get the same sound kinda like fuf fuf fuf fuf while on wot at the end of the rev range. If it was surg you would be getting a different sound plus large vibrations from the engine bay this is caused by makeing more boost then the engine can handle which mostly happens with bigger turbo's or running a lot of boost. Looks like the next upgrade should be the turbo any thing else at this point won't make much gains with the stocker maxing out.

 

Have anyone figured out anything about it? I just had the grimspeed ebc installed and a tune from a reputable shop in my area. What is it?

 

You have a boost leak.
I had the same thing happening to me, blamed my Diverter valve.
I completely disassembled my entire pipes. Re-installed everything and its gone.

Maybe you don't have a boost leak, but when I had this issue, that's what it had to have been.

 

It's the way an EBCS works. If you had an open dump for the wastegate, you would very clearly hear it open and close as the wastegate cycled during spool up.