On my 2014 GT500 with mods. I am having an issue when I come to a stop it hangs the idle with the clutch pushed in for like 20 seconds at 1500 then to like 1200 and then drops to idle. I grabbed a log of it. Would anyone have any thoughts as to why or what I could adjust?
I don't remember it happening at the end of last year that was the last time the tune was changed. Over the winter I did go to a triple pump system from a dual pump system. I also found the supercharger bolts has loosed up after I swapped the belt the belt this spring. So I don't believe so but that is a good thought that I could try and go back to the tune before this and just check to see if it stays or not. When I was on a cruise this weekend I notice that as long as the car seems to be moving it stays around 1500 and then when you come to a full stop it will drop over about 8 seconds from 1500 to about 1200 then to about 1000 then down to idle.
I went back to the previous tune. The hang is a little better. Doesn't hang as long and lower at about 1200. The throttle is a little more touchy in this on. I did a compare. Several things were changed. I took screen shots of the compare. Any thoughts on what to check. I am thinking maybe the throttle angle but not sure.
Interesting I was putting some of the changes back one at a time. The one that seem to work if I take it out is the spark borderline modifier blew desired RPM vs ECT vs RPM error. Seem to help it is coming down to about 1200. But with that one not in but if I but it seem like if I put any of the other changes in I get the issue to varying degrees. Some of them it comes right back others seem to make it happen when coming to a stop from higher speeds but doesn't at lower speeds. So it doesn't seem to be just the spark borderline modifier one. It seem to be a combo or a different setting that is affecting this.
It is still happening. I have been watching for a pattern and it seems to be related to speed. It will stay around 1500 even if I an rolling for 30 second or more. When I come to almost a stop it drops so like around 5 mph. But then after stopping like I had said it drops. So I am wondering if there is a setting tied to the VSS. Is there a setting with VSS that keeps the idle higher?
You can try this if you'd like. Open it against your file and you'll see some of the idle tables I changed. You had the max setpoint at the same as the current setpoint at 850, and some lower than stock numbers in strange places. The ONLY other change I made was the enrichment rate under the fuel/power enrich tab. It had also been lowered. Let me know how it acts. I love sorting out weird little issues like this.
That didn't seem to work. Also actually a few times it was even higher when coming to a stop it was more like 1700 from like 1500. I recorded to logs. The first one is just coming to the stop. The second was a few minutes longer as a turned around and got back on the interstate for a couple minutes and then got off and come to a stop. So you can see it. Would help if I post all the modes that were done so you can see and get more a picture of things. Oh sorry it took me a few days to get back to you with the log. It has been raining here everyday so this was the first chance I had to get out with the car.
Dude I can't believe I missed your torque tables... they are wonky and will really affect idle and drivability some. I rescaled them for you on this edit. Let me know how this turns out. The file name is the same but changes were made. By the way.. I'd love to know the mods and some numbers if you're willing to share!!
ok. I will give it a try. I have not had it on the dyno yet as I want to wait to get the tune dialed in more first. I modeled it after a youtuber MustangeLifeStyle. He was 1350 to the wheels on E85. I am still on pump gas with boostane. So running about 100 octane at the moment. Here are the mods.
3.73 Gears.
Return Style Fuel system from VMP with some mods
Triple fuel pumps
2000cc FID injectors
Custom Cams from L&M 550 lift 112 intake and 118 exhaust.
VMP Gen 3R supercharger
VMP twin 69mm throttle body
JLT 123 cold air
Oil pump gears
Crankshaft harderned Stud
Upgraded Valves
10% overdrive pulley
Forged Pistons from Diamond and rods from Molar
Cobra hardend crack shaft
Raise the compress with the new pistons to 10.5
Larger radiator
VPM Heat Exchanger
Block has been bored and sleeved from a 2014 5.8L. Bore is now 3.700 which makes it about 5.9L now
ARP studs for everything.
Heads and intake have been ported and different valves from Airflow Solutions
2.8 inch pulley on the supercharger (should make 12-14 pounds of boost)
Has track pack option on that has trans and rearend cooler
Fuel pressure is 55 without vacuum
Long tubes and full 3 inch exhaust from Stainless Works
Lower themostat 170
Hotchkis rear suspension
Build TR-6060 by RPM Trasmissions
Billet aluminum chain guides
Accufab secondary chains and CAM gears
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