Switching to stock Chip, with minor overboost problems?

[Syclone#1992]

I am going to switch from ATR Pitbull to the Stocker to see if this cures some of my knock issues. Can I do this if I am pulling 15.2 pounds of boost. I want to lower it but don't know how. I just put the ATR SS Cat on that is why I am getting more boost, Will I get an Overboost code if I install the stocker back in?

Does anyone have a detailed diagram or picture of how to switch chips. I just wanna know what I am getting into. I know that the ECM is inside the glove box. Do you think switching to the stock chip will help with the knock issue?

 

[nick041881]

the ecm is underneath the dash behind the glove box. you have to access it from underneath. take it out and there are 2 little screws that hold on an access plate. remove them and you will see the chip.

took mine out today...took me no longer than 10 min start to finish....
good luck 8)

 

[Richme]

First of all it is not in the glove box, but under it. You should take out the kick panel on the right, then the panel under the glove box. After that I could not explain in words, and I don't know where there is a diagram except for the manual, which you should have to start any kind of project like this. Get Opie's CD manual for $35, and I'm sure it will help you.

Secondly, I would believe the stock chip will not help much anyway. You might just try adjusting the wastegate arm. See if that helps.

Get a manual. :roll:

 

[Eluding]

Well I tried the ATR Pitbull and I now have the stock chip. I can tell that that the Pitbull commands a leaner air/fuel ratio at wide open throttle than my stock chip. Leaner equals a greater tendency to detonate. My 91 Syclone stock chip has a target air/fuel ratio of 11.8 to 1(rich). The street-version Pitbull has a target air/fuel ratio of 13 to 1(lean). I have stock chip wide open throttle oxygen sensor values of around the .930s. The WOT Pitbull O2 sensor values were in the .840 range. I thought the Pitbull was scary lean. I currently have the stock chip in the truck.

 

[Syclone#1992]

Thank you for that info,
I will definately be taking that chip out.

Anyone know the air/fuel ratio on the ultimate?

 

[smeagol]

Yes I do, but I'm not gonna post it, because you guys are misinterpreting it.

I could make changes that show your AFR at 15:1 on a scan tool, yet it'd still run richer than either chip.

The AFR at WOT in the chip & on the scan tool is a value that is entered in a table. It will add or remove fuel as a fueling multiplier, but there are other tables that can add/remove fuel as well. Point is, relying on that value is pointless, it has no bearing on comparisons as you are making. The AFR reading on scan tools is not a sensor read value, it is just a value that is a 'desired' AFR for whatever condition (startup you want richer, warmed up you want 14.7:1, at WOT you'd want 11-12:1,etc). The computer makes no changes/adjustments to correct to that AFR unless it is in closed loop, like idle/cruising.

The ATR chip runs more boost, in open loop boost control mode, with more timing as well. So timing, fueling, or too high a boost level could cause detonation.

 

[Syclone#1992]

Update!!

Update!!

I switched the ATR Chip out for the Stocker :lol: !!! Great Results :wink: I also put 25 dollars of 110 octane in too. Onlg 3.59 a gallon :roll:


But anyways, I am now only geting 1-3 degrees of knock at 15.4 PSI. Wooo hoo :wink: I am so happy!!! At one point it went to 6 but disapeared right away. I still need to hotwire the IC and check the timing.

I am glad I took the Shitbul out of it. I lowered my knock count from 15 degrees to 1-3.
I am going for no knock at all. Changing the chip is simple for all you newbies out there.

 

[InvisiBill]

Did you run on the stock chip with regular gas? Or did you do the chip and 110 at the same time?

 

[Syclone#1992]

I did it at the same time!

 

[Eluding]

Brian I understand what you're saying about the scantool-displayed commanded air/fuel ratio. But my WOT O2 values did drop from the .930s with the stock chip to the .840s with the Pitbull chip. Can't misinterpret that. It indicates a leaner condition. How much leaner I don't know since I didn't wideband O2 test it. But I figure why take the chance running lean I burning a piston. I tossed the Pitbull.