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Fuel New Build Running Lean

  • Thread starter Thread starter mustang 88
  • Start date Start date Nov 16, 2017
M

mustang 88

Member
Oct 21, 2012
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cleveland ga
Nov 16, 2017
#1
  • Nov 16, 2017
  • #1
Please HELP i'm at wits end. I have a boss block 363 with custom grind cam, afr 205 heads, 78 lb fuel injectors, pro m 98 mass air meter, trick flow type R intake, A-1000 fuel pump, 1.75 hooker headers, and i'm using the pro m efi computer that replaces the entire factory computer, vortech v-7 ysi with pulley that came with kit. Once I start the car it take about 2 mins for the headers to start glowing at a idle. I have retarded timing advanced timing and end up with same results. I made a injector cleaner and used carb cleaner to run through injectors, not sure if that could hurt them? I'll take any advice and thank you all i advance.
 

jrichker

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Nov 16, 2017
#2
  • Nov 16, 2017
  • #2
Where's your wideband Air/ fuel ratio indicator? ??

The color or heat coming from the exhaust headers is not a useable indication for air/fuel ratio. You spent $$$ on the engine ,where's the money to spend on instrumentation to get it to run properly?
 
Reactions: General karthief
M

mustang 88

Member
Oct 21, 2012
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cleveland ga
Nov 16, 2017
#3
  • Nov 16, 2017
  • #3
i forgot to post wide band reading, 15.2 should be 14.7
 

General karthief

wonder how much it would cost to ship you a pair
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#4
  • Nov 16, 2017
  • #4
Can you hook it to a lap top and run data on it?
From what little I've read it's tunable.
 
M

mustang 88

Member
Oct 21, 2012
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cleveland ga
Nov 17, 2017
#5
  • Nov 17, 2017
  • #5
Yes you can but it came pre tuned specific to my build.
 

Steel1

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Aug 18, 2017
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Nov 17, 2017
#6
  • Nov 17, 2017
  • #6
I would make a call to Chris at Pro M, I've dealt with him in the past and he has always been very helpful.
 

FastDriver

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Nov 20, 2017
#7
  • Nov 20, 2017
  • #7
Sequential or Batch fire?

Idling in the 15.2 range is not a problem, and definitely shouldn't cause glowing headers. Do you have 2 widebands or just 1? If two, do the readings match? If only one, have you tried swapping over to the other bank to see what kind of AFR you're seeing there?

Next, what is your idle timing set to? If it's too retarded, you might be sending a lot of unburned fuel mixture into the exhaust, which would have the effect you're seeing. Can you datalog and post it, here?
 
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