static_set

I'd like to introduce everyone to a weird issue I've been tracking with the car so far this year and get some opinions on it.

This past April I had my car tuned again to account for the different mods I installed and everything was fine on the dyno. Car made good power, barely touched 28psi, zero knock, everything was (and still is) great.

I granny drive this car and rarely get on the throttle like I'm supposed to so it took me by surprise one day when I high tailed it around a corner on my way home and was immediately thrown into the belts as the car cut the power and threw up the overboost code. I immediately checked the boost gauge and saw the car had registered 31psi.

This made me interested to find out what was going on so the next day on my way home I did the same thing around that specific corner: second gear/3500rpm/stompedWOT and achieved the same results. I made mental notes of the conditions and went on my way. Did it a few more times over the course of the following weeks and could accurately make it cut every time.

Two things had changed since my tune: 1) I installed a deflector plate from YR Advance and 2) I had installed an inlet just above it on the bumper. I use these in conjunction with the piece from APR in an attempt to make ambient temps available to the intake box. In light of these additions, what are the chances that the cars dynamic environment differs to such an extent that sitting still on a dyno would not be able to accurately replicate it? I have no way of monitoring IATs or logging info so it's just a conjecture really - so I'm just here looking for opinions I guess.

A few weeks ago i remembered about an Agency Power half downpipe sitting around that I had never bothered to install so I found the box and installed it *without* getting a retune. Did my usual granny driving for several days and then set the camera on the gauges and monitored a few solid 4th gear pulls so i could correlate the RPM/AFR/Boost variations. Satisfied that the car was still operating within safe limits I left it installed. The problem of the car killing the power has since disappeared but I still hit 30psi which leads me to believe it's a gradual creep rather than a sudden instance like before.

Anyone have thoughts on this? Sorry for the long post - just trying to be as informative as I can.
-asher

LetsGetThisDone

iTrader: (1)

Who tuned it? Even 28psi is a lot for pump gas.

RazorLab

iTrader: (8)

It's not because it's now "moving". It sounds like the dyno didn't replicate street loads or the tuner didn't put the car through the proper paces and now the car is seeing varied load and varied boost.

static_set

It is - Kasey Harris at DynoTime SpeedWorks has done the last two tunes on this car. It runs great. He was pretty adamant about not having any knock counts allowed.

The first time he tuned the car this past winter there was quite a bit wrong with it. The prior shop [wont be named here but they're located in downtown Charlotte and use a rooster for their logo] couldn't even adjust the tune properly for the 214A cams... He spent close to two hours with the car working on the driveability from the ground up before it was even set on the dyno the first time. I do trust his work.

I've also noticed that it's more prone to going over 28 if the car is screaming up or down a hill which leads me to believe you might be somewhat correct. Sometime I just thought about is the road he did all the driveability stuff on is pretty flat. How would I go about confirming that this is what's going on?

-asher

static_set

So I'm bringing this back from the dead because the car found boost cut again.

Yesterday I downshifted into 4th at highway speed and found the cut at 32psi.

Car will consistently touch 28psi for a couple hundred RPM while on the dyno.

-asher

RazorLab

iTrader: (8)

So have you talked to your tuner yet?

static_set

I have. He has said he factored in higher load levels, less timing, and more fuel so the car would be able to operate safely. I'm no tuner so the only thing I have to go off of is "it was tuned at 28 and constantly see's 31+"


I've recorded pulls in the past on video and the car never runs lean at any point so I know it's operating okay - just throws me for a loop when the car is running as strong as it is when everything I read says it shouldn't be.

-asher

LetsGetThisDone

iTrader: (1)

You should not be making that much boost. Maybe its time for a new tuner.

static_set

I'm tempted to try another, but there aren't any within driving distance that I would actually trust other than the guy I'm using.

Chef-j

iTrader: (16)

So he doesnt know why you are overboosting?

Well buy tactrix and time for Etune.

static_set

This guy/shop isn't a noobie and has been successfully tuning evos for at least twelve years. He knows what he's doing and could be considered one of the best in the country... That's why I honestly don't think it's the software making the car do this.

I'm very tempted to buy a Tactrix cable just so I can get some logs of what the car is seeing. I wouldn't have the first clue about what I'd be looking at, but the capability of logging some info on my own would be handy.

On an updated note:

Over the weekend him and I logged a few pulls. He adjusted the boost levels and now the car will not go over 27 regardless of what I do. Downhills, uphills, straight and level, downshifting to WOT around a corner, sudden WOT to vacuum back to WOT - and it's great. He noticed a couple spots where the car was running a tad rich and pulled fuel to smooth out the curve. The car feels a little better than it did before.


I'm keeping a close eye on it for sure.
-ash

static_set

Well guys,

It's back up to it's usual 30psi consistently. Looks like I'm gonna need to haul it up to CBRD for a good jam session because I've just about had enough of this drama.

-ash

4b11slayer

Maybe you have a controller issue or guage issue.