Hey guys, got something going on I can't seem to figure out, was hoping some of you might be able to point me in a direction before I just start buying parts.

First off, I was just tuned about a month ago at National Speed in Wilmington, NC. Those guys are great, and really made me feel like I was at home. They have continued trying to help me through emails after the fact, and I plan to stick with them for future work. I made 342whp and left the boost set at 23lbs.

With that being said, here's a list of my mods and the issue in question.

2005 GSR, stock turbo, forge wastegate actuator, synapse recirc. valve, IC pipes, IC, turbo back exhaust, spoolin' up coils, few other odds and ins.

While being tuned, the tuner noted that my boost was going up and down up and down, and after driving it and full boosting it, I can see what he meant when he was pointing at his laptop. When under WOT, at full boost, there is not a constant spool sound, but rather a fluctuating up and down whistle sound, as if the fan is bouncing back and forth between moving faster and slower....WHISHwhishWHISHwhishWHISHwhishWHISH(best I can do lol).

What's weird is the boost gauge doesn't seem to read the fluctuation. It doesn't jump around, just shows me full boosting at 23 lbs. While approaching 130 mph I looked down and my boost gauge hit 31 lbs! I immediately backed off. Car runs fine, just as before, nothing blown, everythings normal, but I certainly have something crazy going on, two issues, possibly linked?

The previous owner of the vehicle installed a perrin electronic boost controller. I was advised to buy a hallman pro and go with that, as well as check the spring on the waste gate actuator, although i'm at stock boost levels so that shouldn't be the issue.

Help?

 

Can you take a video and post it?

Check the line going from the ebcs to the wastegate. Make sure that it is hooked up correctly. I would guess that your boost tables and correction tables are not setup correctly for the 3-port (which is why they suggested to run an mbc as they don't know how to setup a 3-port).

 

please do not talk about street racing on this forum

 

get rid of the EBC and go manual or ecu controlled GM 3 port--that whooshing sound your hearing is bleed of of boost but not in a consistent linear manor as you will get with those options mentioned. GL

 

The perrin is an ebcs, not an ebc.

 

The 3rd port on the Perrin is not being used. Only one line coming in from the intake manifold and the line going out is routed to the wastegate actuator. A MBC seems to be the most simple fix.

 

^^This. If your tuner prefers tuning on a MBC, there is probably a reason why. I would say take the advice and get a MCB and get it re-tuned or i would go with a 3-port and have another tuner redo the tune. keep us posted! good luck.

 

Also, improper set up of a 3-port boost solenoid will cause the huge boost spike.(not a good thing).

 

Let me check the hoses real quick...

 

kyoo: I did not once mention "street racing."

http://bit.ly/MDxf9N
^^^

Everyone else: Hoses appear to be fine. And thanks for the help, I believe I will go with the Hallman after all. So if I switch to the mbc, I will need a re-tune? Yikes

Also, there is an electrical connector coming off the ebcs running to a factory harness, this can't be used with the hallman. Do you just let it hang? What's the deal with that one?

 

my fault, i meant illegal street activity. thanks.

 

No prob brother. Anyways, just ordered a hallman pro, when it comes in i'll throw it in and update this with my findings in case it helps someone else out with similar issues. In the meantime, can someone educate me why I would need a re-tune if I switch to a mbc, as I won't be going any higher than the boost I was tuned for previously?

 

WELL........!!!

So my Hallman came in, and today my buddy and I installed it and did a few pulls, adjusted the forge wg actuator rod, needed to dial down the preload so that I could build back up with the controller. Now something else weird is going on...

After installing the controller, and before adjusting the wg, it was hitting 25lbs right off the bat(how we were led to adjusting the wg) but anyways it was building boost just as quick as ever. So AFTER we adjust wg down, on my way home, and driving through town, I noticed it is now building boost noticeably slower. Is that a symptom of messing around with the wg?? What's going on with that.......somebody must have experienced this before...i'm hoping lol.

I was told by forge that I have the 19-25 lb range spring. After adjusting wg rod, I'm wondering if it's just too loose now? And should I replace the spring I have with a lower spring, and then build boost with my controller? Would this fix the slow spool rate??

 

Bueller......Bueller...........

lol