Switched to SD

[urmomsaniceguy]

So last night I installed my GM 3 bar MAP sensor. I locked intake temp. and switched to SD. car seemed to idle fine. Car drives great. I do have a few questions or clarifications if you will.


1. Do i absolutely need an IAT?
2. Do i need a WB?

I have a log of it at idle and also i quick 1st gear pull. For some reason I am only at 10lbs of boost in any gear. Maybe i dialed in the WG settings wrong. Any positive feed back will help.

The first log is idle and the 2nd log is a short first gear pull, for some reason the idle was high. please help.

 

[gofer]

1. Running SD with no IAT sensor is possible but the ECU assumes 77* all the time so its unable to adjust as air temperature changes. Of course its going to be more accurate to run SD with an IAT but you can get away without one, just make it temporary. Its just hard to get a good SD tune because as temperature increases you'll start running a richer fuel mixture.
2. YES!
3. A first gear log isn't going to tell you or anyone else what changes in the tune need to be made. Do 3rd gear pulls from 2.5k to 7k (safely of course) and if you start seeing the CEL flashing get off the throttle.
4. Personally I suggest ZERO'ing your fuel and timing sliders and tune solely from your SD VE table and DA OpenLoopMaxOct/TimingMaxOct tables AFTER you get a wideband.

The first thing to check when it starts idling high is sufficient slack on the throttle cable, if its too tight it will open the throttle plate just like your giving it some gas. Your ISCPos is low as well (10-) and it should be right around 30- at idle. To adjust it start a log and pop the hood while your cars idling, adjust the BISS on the throttle body until you get ISCPos to 30-.

 

[urmomsaniceguy]

Tuck. I didn't know about the ISCpos thing. I'm looking for a WB as soon as I Can sell this 16g.

 

[the_mork]

Don't turn your car on again until you've switched back to your previous setup.

Switching to an entirely different air metering system, especially without fully understanding it without a wideband is foolish.

I don't mean to sound harsh here but really you've chosen to do something that could have disastrous consequences for your car if it is not monitored and done correctly. I love running SD but it is in no way worth it to switch without all of the groundwork covered first.