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Brain MS3X Idle 'Issues' (Idles at 3k)

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Old 04-28-2017, 12:05 PM
  #181  
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I started off with this ignition map. It knocks everywhere even at low loads. So unless you use E85 or race fuel be careful.
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Old 04-28-2017, 12:29 PM
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Originally Posted by yossi126
I started off with this ignition map. It knocks everywhere even at low loads. So unless you use E85 or race fuel be careful.
'This ignition map'? Did you mean 'his ignition map' referring to brains?
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Old 04-28-2017, 12:42 PM
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Way more than your meds school debt. Reduce the timing one degree in the area of the map and see it goes away, like Aidan said.
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Old 04-28-2017, 12:52 PM
  #184  
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Got it. I'll look at the VE table and spark table while going through the log and pull timing there.

Thanks folks!
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Old 04-28-2017, 12:59 PM
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there's a lot less timing on my NB map in low loads than my NA map (first knock complaint ive heard in hundreds of installs)

the NA map I load is what I actually ran on my car for years.
the NB map is based of Y8s map, which is based of the Hydra map.

Listened to both on a few setups using detcans, never knock.




I just don't see you really knocking with this map...
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Old 04-28-2017, 01:26 PM
  #186  
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You're running about 3º more (~33º) than I do (~30º) at 5500rpm and 99kpa. My tune is fairly conservative too. Brains standard NA map also runs a little less timing at 5500rpm and 99kpa when compared to his NB map. I really, really doubt you're knocking there, but if you want to be absolutely sure, just reduce timing by 3º, as Aidan already suggested, and run it again.
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Old 04-28-2017, 01:27 PM
  #187  
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I'm not certain I'm knocking, but I have that 25% spike in all the logs I've looked at where I'm in WOT. My fueling there isn't the best, but it's been getting better. I'm just trying to figure out what's going on and if this is something to worry about.

Stefanst, I'll try that next time I'm in the car and see what happens during a WOT pull.
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Old 04-28-2017, 01:58 PM
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your knock threshold is 60% btw, you're seeing about 25% on some noise spikes. I dont think you're close to the % needed to think that youre close to knock. and those numbers are typical from what ive seen on logs.

looking at, i would say that map is actually a little aggressive for n/a. I'd prefer the 110 row to be the 99 row.



what i dont understand is your AFR in your logs as you approach redline... at 6800 on every log, your AFR goes full lean -- despite having same pw and spark advance. that is your soft limiter number, but im not seeing in the logs the timing or fuel being pulled.
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Old 04-28-2017, 02:04 PM
  #189  
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Originally Posted by Braineack
what i dont understand is your AFR in your logs as you approach redline...
He has soft limit on rev limiter set to 6800rpm
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Old 04-28-2017, 02:08 PM
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Originally Posted by stefanst
He has soft limit on rev limiter set to 6800rpm
but nothing is being cut:



but that does appear to be whats happening, since the rpms slow up.
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Old 04-28-2017, 02:15 PM
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Brain, the rev limit is set at 7200 with a 400 rpm hysteresis. So it's 'soft' cutting as far as I know. It definitely doesn't feel like railing into the limiter with the stop ecu.

The image you posted also captures the 'knock spike'.

Last edited by ridethecliche; 04-28-2017 at 02:29 PM.
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Old 04-28-2017, 02:16 PM
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yeha i know it starts to cut fuel to each clyinder until you hit the redline, im just surpised it didnt show up in the logs...

still, i dont think youre seeing knock. you see 25% "knock" on decel with no load.
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Old 04-28-2017, 02:18 PM
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It's the progressive fuel-cut feature if I understand it properly. It starts cutting of fueling events as soon as you hit the soft-land limit. So PW is unaffected, spark is fine, but we're still getting air int he exhaust.
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Old 04-28-2017, 02:19 PM
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i just would have expected to see the pw on each cylinder start to drop off, but yeah i understand that's how it works.
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Old 04-28-2017, 02:30 PM
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Originally Posted by Braineack
your knock threshold is 60% btw, you're seeing about 25% on some noise spikes. I dont think you're close to the % needed to think that youre close to knock. and those numbers are typical from what ive seen on logs.

looking at, i would say that map is actually a little aggressive for n/a. I'd prefer the 110 row to be the 99 row.
I'm probably going to be installing the turbo stuff over the next month or two, so no need to go nuts with the changes, but I can definitely save the current timing map and make that change and then change back to the current map when I get the boosty stuff done. I can talk to you via email about a basemap for bewst, but looking at the ranges in this map it seems like its set up to handle some of that ish as well.

Also, that means that any 'real' knock I'll see will be closer to or past the 60% threshold, correct?
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Old 04-28-2017, 02:33 PM
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when you add boost your youll see a rise in the noise. when you get real knock, youll see it spike up pretty significantly. you want the threshold to be high enough it filters out noise, but low enough it'll catch real knock.
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Old 04-28-2017, 02:50 PM
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Thanks Brain.
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Old 04-29-2017, 09:43 AM
  #198  
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Originally Posted by Braineack
there's a lot less timing on my NB map in low loads than my NA map (first knock complaint ive heard in hundreds of installs)

the NA map I load is what I actually ran on my car for years.
the NB map is based of Y8s map, which is based of the Hydra map.

Listened to both on a few setups using detcans, never knock.




I just don't see you really knocking with this map...
:like cat: for posting differentiation of Spark for NA vs NB. From the looks of it, I'm guessing there is more going on than just the Compression Ratio. So often in discussions on timing, important variables, like CR are left out of the conversation.

Were these developed for 93 Octane fueling?

Why the step at 35kPa and 4800 RPM?
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Old 04-29-2017, 04:14 PM
  #199  
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I think he does the step at 35 and 4800 since those are usually low load states that you'll see during vacuum when you let off the gas. You're going to be there for less than a split second if you're giving it any gas at that point and you'd jump way up in load right away.
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Old 05-01-2017, 01:59 AM
  #200  
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Update!

Got my car running on the mustang injectors with the FF kit. Things run pretty well!

Except at idle...

It idles totally fine off the bat, but tries to die at every stop light. At times at start up, it'll settle into an rpm, then jump up and come back down again with no throttle input.

The good log I have was too big, but this log is similar. It leans out around value 350 and tries to stall. I've tried adding more fuel to the VE cells in the lower ranges, but it didn't seem to help things much. I'm going to try adding even more tomorrow. Any advice would be much appreciated.

Re: installing injectors
I changed the dead time to 1.1 and scaled reqfuel by using 630 for the new injector size. I want to set a new dead time curve, but the values on the force flow site are in absolute numbers and TS is in percents. Does one just covert and go from there?

And brain. still haven't figured out the noise. Its been happening intermittently now. I keep forgetting to change the idle valve setting.
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