Car running 67 maf flow rate lb per min

[kufty]

I’m not a mechanic or know much especially about tuning and datalogging but i’ve been having issues with my car, i’m on a cobra jet setup w a 65mm twinjet tb, long tubes no cats on a gen 1. Datalogging shows about 67 maf flow rate lb per min at around 7800rpm. I’ve already tried a new DW400 fuel pump twice but it didn’t solve the issue so I wanna know what I should look out for or what else can be causing that, If appreciate the help thanks!

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[engineermike]

67 lb/min sounds high for an na car. Are the fuel trims way negative? Could be a bad maf transfer function.

 

[kufty]

67 lb/min sounds high for an na car. Are the fuel trims way negative? Could be a bad maf transfer function.

If you’re referring to lambda, car hits .90 at 7800 which is also bad, but i can’t figure out the issue and it’s remote tuned so I cant really take it in to my tuner

 

[engineermike]

No, the fuel trims.

 

[kufty]

No, the fuel trims.

It sits at +1 on my WOT log

 

[SheepDog]

Datalogging shows about 67 maf flow rate lb per min at around 7800rpm

Not unless you're making 600+ HP.

Has it always been this way, or did the logs recently change?

What are your fuel trims at Idle and cruise, not just WOT

Who tuned your car? Could just be that the MAF Scaling is wrong, for whatever diameter your intake/MAF housing is.

 

[engineermike]

Either it’s making some serious na power or the maf curve is bad along with the injector data (assuming he’s looking at fuel trims correctly).

 

[kufty]

Not unless you're making 600+ HP.

Has it always been this way, or did the logs recently change?

What are your fuel trims at Idle and cruise, not just WOT

Who tuned your car? Could just be that the MAF Scaling is wrong, for whatever diameter your intake/MAF housing is.

It’s been like this since I put on the cobra jet setup, before that car was stock no tune, when i’m cruising at like 60mph 2500rpm the fuel trims are 1.0-1.10, i don’t have any recent idle logs, this is all on e85

 

[kufty]

Either it’s making some serious na power or the maf curve is bad along with the injector data (assuming he’s looking at fuel trims correctly).

I don’t know if it’s making all the power it should, my 60-130 is around 9.4 seconds (i don’t know if that’s good or bad for the setup i have)

 

[kufty]

Not unless you're making 600+ HP.

Has it always been this way, or did the logs recently change?

What are your fuel trims at Idle and cruise, not just WOT

Who tuned your car? Could just be that the MAF Scaling is wrong, for whatever diameter your intake/MAF housing is.

Sorry i forgot to say but it’s tuned by Tricky

 

[Pistol_91]

I don't understand what the problem is here you're trying to fix.

 

[kufty]

Either it’s making some serious na power or the maf curve is bad along with the injector data (assuming he’s looking at fuel trims correctly).

I just checked for codes, p0507 popped up because the car was idling weird jumping to 1k, is this a separate issue or can it be connected to the car running with too much air?

 

[engineermike]

Unlikely.

 

[tdstuart]

I have seen this issue with a tuner I used where the car looked like it was using enough air and fuel to make 900hp but I am n/a.

If the injector data and airflow data are both off it could produce the results you are seeing.

I am not sure if the tuner I was using was messing with injector data. I don't see why he would, I think there was another set of parameters he was changing as he was having an issue tuning the car due to the cams. I would have to pull his tune to know for sure. I feel like he was doing something with the torque calculations but I remember it resulted in a really high injector usage and duty cycle that wasn't real.

Tricky should have the right injector data for your injectors so if the fuel trims look good your airflow should be right, but 67lbs is not right unless you are max max effort an.

What injectors do you have?

 

[markmurfie]

Flex fuel tune?

The adaptive stoich logic can trip up even the best tuners, espeaclialy if they are remote and are not thinking about what E% the car actually has in the fuel tank.

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