I had been running stage 2 for the past month or so and I decided to install the ebcs and intake yesterday and flash the stage 3 map. The car is running well and there's no apparent leaks in any of the vacuum lines but the car will not come anywhere near target boost, which is 26.5psi +/- 1.5psi. I have notice a small amount of flutter but its very intermittent and I cant seem to make it happen on demand. In second gear I have only been able to hit around 22.5psi. Anyone have any suggestions as to what could be causing the issue?

 

Using the COBB EBCS? I have Grimspeed and its making too much boost

 

http://www.evoxforums.com/forums/att...3&d=1226120607

Try that. Be careful, you can overdo it. I would only hit 21-22 psi until I increased the preload by 1 turn. Now, I am 26.5-27psi.

Also, triple check that all intercooler connectors are tight. It is possible your stock BOV can be leaking, so you may want to try a crush. This will give you an idea of how.


And this link has info on what do to.
https://www.evolutionm.net/forums/ev...asy-works.html

 

Now Im more confused, Ive started hitting around 25.3 on an irregular basis. For the most part though, I still cant get over 23. I have noticed that I get a significant amount of flutter during wot in 5th gear, has anyone else noticed this with stage 3? It seems that it only happens in 5th gear.

 

Yes. That will happen. I have altered the map on the Tip Out Enleanment to be progressively less pulse width in the lower RPMs (cruising RPMs) to help keep this from happening. I also VTA, so not only would I flutter, I would get bucking.

Do you hit that higher boost in lower (2-3) gears in cooler weather? Maybe with a punch of the throttle rather than a roll on?

What downpipe/cat are you running?

 

I was able to reach 25.5psi today in second gear from a slow roll, it does seem to be in the higher gears that I am unable to reach target boost. And Im running the cobb testpipe and catback, still have the stock downpipe though.

 

I would do the wastegate mod and watch knock on your AP. Also, having stock downpipe will affect boost in higher gears. Don't waste your $$$ on the Cobb or any other "short" downpipe. Save up and get a full downpipe like a ETS or MAP. I personally run the MAP recirculated.

 

Im thinking about trying the waste gate mod but the only thing that worries me is that I will from time to time hit ~25psi. If I do the waste gate mod do you think that this could lead to over-boosting issues bc you said that one turn of the clevis resulted in a 5psi increase. Im starting to wonder if there is a boost leak but I cant imagine where it would be, I haven't disconnected and high pressure lines besides where the ic piping meets the turbo and Ive made sure that it is sealed.

 

Yes. I initially did 2.5 turns and hit 30psi on a cold day. Backed off and now I am steady at 26.5-27.5psi at WOT with almost no knock (some noise).

 

With the Stage II OTS map I was over boosting/boost spiking on WOT from the low 3ks all the way to redline. Added the Cobb EBCS, loaded the Stage III map and It just hits 23 psi, and doesn't start to build until 3800. When it's colder (40-60 F), I can get a good 25 psi and a 500 rpm sooner build. I'm used to the lag and my data seems fine, though I would love to have it tuned right.

A friend has the same mods with a pro tune from Plano and he starts building boost with gobs of torque in the low 3k rpms and the power band is tremendous. Seems to be large gap between the OTS and Dyno tuned maps.

 

That makes me feel a little better, I plan on making it out to AMS this summer at some point so I was more concerned that there may be some sort of leak or other issue that might arise while getting tuned. If its just the way the OTS maps run, I can live with it until I get tuned.

 

Oh absolutely. Calvin (Pro tuner at Plano) is a bad a$$. I am getting floors installed in my house this week, then he's doing a ProTune for me. I'm on the fence about dropping for injectors. ProTune from Cobb is $400 for single fuel, $600 for dual fuel/E85. Hmmmm.