Interesting fuel issue- any thoughts?

encasedmetal

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So I recently swapped out my procharged f1a setup for a kenne bell 2.6h setup. nothing in the fuel system changed except for the fuel rails. I also changed the maf to a SCTBA2600 (not fuel system related). When I confirmed all vacuum leaks were addressed (first start idled at 1700rpm), the car would not fire anymore. soaked plugs and strong fuel fumes led me to pull fuel out of the maf table.
When I started the tuning for the new setup I used two different tunes to weed out solutions- one tune was from that of a car using this exact setup and went 9.xx's so it should've been really close to what I needed. The other tune was a startup tune I put together. both tunes required me to pull 35% fuel out of the maf table for the car to fire- and it still idles at 11.4-11.7 afr. Something is going on and I don't know what it is. I shouldn't have to pull that much fuel out. adaptive is turned off, and I set fuel pressure at 39psi without a vacuum source, and it reads 30 psi with the vacuum reattached. any thoughts? I have a datalog of it idling but it's not attaching in it's csv file format.
 

01yellercobra

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I'm wondering if that's your issue. Since you had to load a different tune for the MAF. When I first installed my 80's I had to pull 25% fuel just to get the car to fire up. It wasn't happy during that start either. I wanted to say I pulled in the neighborhood of 50% to get the idle close to stoic. That was on my big bore set up too. I imagine it's worse on a 4.6.
 

01yellercobra

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I had to pull fuel all the way up. When I first started doing WOT tuning it was so rich it pegged my wideband and left a black cloud behind me. A good wideband on a dyno showed my A/F in the 9's. It's just the data for these injectors isn't the greatest. That's why they take some work to get to run correctly.
 

01yellercobra

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Check the minimum pulse width. I remember having to lower mine to get better idle control. I made mine the same as the 60's.
 

lowranger96

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Specs for the 80s:

Low Slope 101.459 (0.0281830555555556)
High Slope 75.157 (0.0208769444444444)
Breakpoint 0.00002421

Min PW set to 0 so that you don't clip it
 

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