Cold Start

mustang70

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I'm finally getting down to the small details. The current one is the cold start. For the first start of the day the RPM will fluctuate a bit before settling down. I tried to get that in a log, but it was just a little too warm to hit that part of the WUE table I guess. Once it settles I can let it idle all the way to full warm up with no problem. However, if I try to drive the car before it's fully warmed up it'll bog like crazy and the A/F will go extremely rich. I usually have to rev it to get it to "clear up". Once it's warmed up everything is fine. Is this an accel enrichment thing? Or am I overlooking another table somewhere? Hopefully the issue shows up in the short log I took. I moved it from the street to the driveway.
 

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a91what

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The engine is drowning in fuel, your acceleration enrichments are way off when its cold. I would assume they are also off when it is warm based on some of the settings. I question some of the other settings as well, your ignition table is very flat once you enter boost and you are pulling a very aggressive amount of timing with intake temperatures.

This picture is a comparison of your settings with settings from a tune I did. I am mainly concerned with the settings in the right column to get the cold accel values corrected.
Accel settings for mustang70.PNG
 

mustang70

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Everything is conservative because I'm running 18psi on 91 octane for now. I did recently change to a colder plug after having some knock issues at WOT at higher timing. I've always set up WOT with locked timing. Maybe it's just an old habit from my SCT days.

I tuned the accel by feel. Those setting are what it took to go into accel enrichment. Before the accel indicator would never come up. The rest were done to get the car not to hesitate when going from overrun to back on the throttle. The rest of the curve was to be able to punch it while rolling. It would hesitate bad then take off. What I found showed that's really what it comes to. Maybe I was wrong on that.

Most tuners start pulling timing around 120 degree inlet temps. At least on pump gas. And it doesn't take more than a couple pulls to see 130-140 degree inlet temps. Maybe once I get the knock sensor working I'll play with that more. But for now I'll keep it conservative just to be safe. The wife said if I blow this engine I'll have a garage ornament for a while.

I must be misreading the Full Accel Below. I took it as below that it would give full accel enrichment control. Above that there's no control.

I will say is laid down 603rwhp and 568ft-lbs before we got locked down.
 
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a91what

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Where are you reading intake temps from? I suppose i assumed the sensor sees heat soaked air in the manifold, without a full datalog to view I cannot see what normal intake temps are for this build. 90% of what i have tuned across multiple platforms see more than 140* intake temps full time.
 

mustang70

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The inlet sensor is in the back of the blower base. It's reading the temps after the intercooler. Depending on ambient temps I can see cruising temps between 100-120. On a cold day (70ish degrees) it'll show even lower. I attached a log that I pulled from the SD card a couple weeks ago. It should show more of the MAT temps.

Do those set ups not have an intercooler? I remember with my air to air set up it was never more than a few degrees above ambient.
 

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a91what

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Alot of them do not, most of the sbf stuff you will look at have it in runner #5 and it sees very heat soaked air. Your temp values are what most see if they relocate the sensor into the inlet
 

mustang70

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I'm guessing that's with the intake in the engine bay. Plus an aluminum intake sitting on top of a hot engine while soaking in a hot engine bay doesn't help things.
 

mustang70

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So this is where I talk about my learning process and talk about where I screwed up. I was watching the Accel indicator under Engine State Settings while I was driving. I didn't realize there was a TPS Accel indicator on the main screen. Once I saw that I realized I was in the wrong spot. So I completely revamped my accel enrichment table and things are working a lot better now. One more box checked. I do need to get a datalog with the most current revision to double check a couple things. But overall I'm happy.
 

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