I already called Shiv to discuss and I'm waiting for the call back, but I figured I'd post here and see if there are any other bright ideas while I wait for the man himself to call me back.

I had Shiv install and tune the XEDE/Flash/SMART set-up on my Evo IX RS a couple of weeks ago. Car already had a turbo-back exhaust and Injen intercooler and plumbing. During the tune we ran into a problem -- the car would not get above stock boost. It hits 19lbs and simply won't go beyond that. The dyno numbers were poor (270whp, but dead consistent), and the area under the curve was also poor. Very disappointing for a IX.

Shiv thought it was caused by the Injen intercooler or a boost leak. So, we called it a night and decided to reschedule until after I could chase down why it wasn't boosting.

So, at Shiv's suggestion I swapped the intercooler back to stock and no dice. The car still won't boost beyond the stock limit. We checked for leaks again, and also no issues there. Nothing we could do could get it to go beyond the stock limits.

Finally, we plumbed in a manual boost controller and -- lo and behold -- the car will boost as much as we want. What the heck is going on here? I'm not an engineer, but it looks like whatever is going on with the boost is electronic.

Any suggestions?

 

Was the xede in control of the boost? That’s weird that it could not boost beyond 19 psi.

 

I think I recall reading in some previous threads something about needing to add something in-line with one of the boost lines from the boost control solenoid and taking out the pill... if you have not already done that. Please correct if I am wrong.

 

For some reason the Xede box is not controlling boost. Have Shiv swap a different Xede unit and see if that works. Something in the unit is malfunctioning. If it still does not work, then swap a new harness and see if that is the problem.

 

the injen pipe set up makes no difference ive had both stock and injen and logged with both. AFR was nearly the same 11.0 stock all the way through richening up at the high RPM range and about 11.2 with the injen with the same curve as stock box. I would guess that SMART really works.


I've had issues with boost the day I bought my Xede, I posted he with my problem and for weeks people kept telling me I used the wrong light green wire so I quit posting and talked to Dustin myselfand he was very helpful. I finally convinced them to take a look at my Xede harness (no output to boost sol when commanded from Xede)however I've yet to send it in BECAUSE I'M HAVING A NEW BABY BOY!!!! So Dustin if you read this thats why you haven't gotten it yet


Thanks to Dustin and Vishnu for your patience

 

That's an interesting hypothesis. The current boost pattern is so damn close to the stock behavior that it very well could be something that simple.

Shiv got back to me and I'm trying to find a day when I can bring the car back so we can sort this out. I'll ask him about the potential for a bad XEDE unit and see if he can bring a spare.

Incidentally, since we need to get back on the dyno to do this, I plan to install a set of Cosworth cams before the dyno day. Should be nice to see what kind of performance we get out of them.