Magnuson Supercharger, Valve Train and other supporting mods. 2007-2013, 5.3L Chevy Tahoe

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Chrismnj

Chrismnj

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thats not lean? are you using a stand alone gauge or reading whatever is logged?

if your just cruising afr should be close to 14.7, wide open throttle with power enrichment (not sure if BBT has boost enrichment set up, not really needed) should be low 11s afrs

what did you end up doing for injectors?
Agree 14.7 at cruising around town and highway throughout all gears , but not 11 cruising on the highway on higher gears. I didn’t even go WOT yet, and yes it is stand alone gauge, as far as fuel injectors they are what ever came on SC not sure how big, but from my research most people change them to bigger. Which is always possibility, if you know what i mean lol

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Just to be clear I am at 11 cruising on highway maybe at 30% throttle, no boost, I am most certain at wot A/F should be at 16+ to the end of the scale and vice versa. But please correct me if I am wrong.
 
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randeez

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Nah..lower number is less air to fuel (rich). If bbt is still updating tune 11afr is plenty safe wot, theres prob some transient fueling trying to nail down. Better to be safe.

Naturally aspirated you can get away with a lean cruise 15.2-.4 , and it does help mpg but I wouldnt do it with any kind of FI, ecm wont correct fueling a crack of the throttle fast enough.

I think I have mine set up power enrichment 12.5 afr (out of boost), and a tapered transition to boost enrichment 11.5afr around 5psi.
 
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Chrismnj

Chrismnj

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damn it I did say 11 was lean, lol. Must be on something
 

randeez

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All good, just want to make sure you're relaying correct info to bbt. You tell him its cruising lean, he going to keep adding fuel making it "more lean" lol.

Usually when the afr doesnt match the commanded it's injector scaling if all else is correct or grabbing commanded value from a different table. Ecm will use fuel for other functions seamlessly with the stock tune but when you start making changes they adversely effect other tables and cause some random stuff, it's a lot of fun. :banghead:
 
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Chrismnj

Chrismnj

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Weird situation, took the truck for a ride, highway and city driving no more codes.
 

bottomline2000

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Weird situation, took the truck for a ride, highway and city driving no more codes.
The ECM could be adjusting. Do you have anyway to datalog your a/f ratios? I have mine tied into my EGR port. BB should be able to adjust the tune and like I said they are conservative on the initial tune especially with a blown engine. Its definitely going into power enrichment early if its showing 11xx at 30% throttle with no boost..its in bypass mode..but hey I'm just an internet expert lol..

Sent from my SM-G975U using Tapatalk
 

97audia4

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I would take back and get it Dyno tuned , that will correct any drivability concerns
 
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Chrismnj

Chrismnj

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Waiting for BB to review my driving log and make his corrections
 
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Chrismnj

Chrismnj

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Planning on re-doing my front end suspension, should I go AC Delco or there is much better aftermarket solution?
 

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