Lund Flex Tune - E85 looks odd, Thoughts?

[Demon Coyote]

My brother was having false knock issues as well with his 14 GT with 47# injectors and Steeda intake, and GT500 axle backs on the flex fuel tune from Lund. We couldn't figure out where it was coming from. So we ended up adjusting the exhaust and steeda intake and still had no luck because whenever I looked at his logs it was always showing knock up top after about 5k rpm. My brother had taken the car to ford before for an exhaust leak where the H-pipe connects to the headers and turns out that was the culprit. After he got a new stock h-pipe and replaced the old one we checked everything once more and I looked at his logs and the knock was gone. He checked with Lund after and everything looked good.

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[venumous]

My brother was having false knock issues as well with his 14 GT with 47# injectors and Steeda intake, and GT500 axle backs on the flex fuel tune from Lund. We couldn't figure out where it was coming from. So we ended up adjusting the exhaust and steeda intake and still had no luck because whenever I looked at his logs it was always showing knock up top after about 5k rpm. My brother had taken the car to ford before for an exhaust leak where the H-pipe connects to the headers and turns out that was the culprit. After he got a new stock h-pipe and replaced the old one we checked everything once more and I looked at his logs and the knock was gone. He checked with Lund after and everything looked good.

Thanks man!

 

[venumous]

None of my lund tunes have ever seen positive knock at WOT. I did get some when I had a BAMA tune, but that was from false knock. Header was contacting the ac bracket bolt. Once I fixed that, no issues again. Like I said, the fact that it's knocking on E85 at 30ish and pulling that much timing leads me to believe that it's fuel quality, or false knock.

I'll have him test the E85 but last year at this time it was E85+ when I had my STI running on it (same pump).

 

[dubster99]

My vote is false knock somewhere. But it's a good idea to test periodically....even though the flex tune should adjust either way.

 

[Obsol3te]

OP
I was originally tuned with Lund when I was N/A
I went and did my header swap and had my tune revision handy and loaded it right up.
Went to dyno the car within a few days and it showed barely a 10whp increase.
Looked further into it and I was showing positive knock. I notified Lund and they ran me through the same BS. Check for Exhaust rubbing somewhere, buy an oil catch can, try torco etc.
Did it all as per their request. Same results, lots of positive knock.
End result, I bitched to lund saying nothing I've done on my end has improved this PLEASE look at your tune. They finally did and the knock was gone.
Long story short, its probably Lund.

 

[dubster99]

What in the tune would make it see that much knock and pull that much timing? It's not commanding anything crazy or out of the ordinary. I was running 31* on E85 all the way up. His looked to be commanding around 30* based on what the KS pulled and what the timing fell to. I'm just not sure what in the tune would cause that, but I'm not a tuner.

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