How much can LTFT's vary between bank 1 and bank 2?

[vettenuts]

My LTFT's seem to be consistantly different, with bank 1 showing about 1-2% different than bank 2. Is this normal?

[TAQuickness]

1-2% should be ok. then again, i haven't run in cl in a very long time

[SSpdDmon]

Yes it's normal

[Joel_SS]

Mine does the same thing.. they are about 1-2% apart.

[joecar]

1-2 is normal (consider this: the exhaust paths from each bank have slightly different lengths).

I occasionally run CLSD to see if I have leaks.

[ringram]

Yes, mine was the same. 2-3% thats why I went open loop so they both got same fuel. Now I dont know :)

Im about to do the same as Joecar as Ive just got a new exahust piece put in.

[SSpdDmon]

Yes, mine was the same. 2-3% thats why I went open loop so they both got same fuel. Now I dont know :)

Im about to do the same as Joecar as Ive just got a new exahust piece put in.
I was about to switch to OL too, but.... I kept noticing the passenger side O2 reading a consistent 10~20mV higher than the driver side under WOT. Fuel trims are always taking more out of that side too. The O2's sit in the same spot in the exhaust on my car since I have long tubes. That's why I started believing the fueling is right in closed loop. My explanation was...I think the passenger side of the motor doesn't get the same amount of airflow as the drivers side due to the intake design. The bank 2 cylinders are offset behind the bank 1 cylinders because the rods can't attach to the crank in the same spot, right? So, it's almost like the passenger side of the motor is getting sloppy seconds when it comes to airflow in the intake. In other words, the first cylinder in bank one is closest to the fresh air coming in...then the first in bank two....then the second in bank 1...and so on. The last cylinder in bank two has it worst of all. I wonder if we had dual throttle bodies sync'd up (one for each bank that sat inbetween the 2nd and 3rd piston) if this issue would go away.?.?

[joecar]

On F-body LT's, the RHS primary bundle has a shallow angle to the bottom, where as the LHS primary bundle has a 90 degree bend at the bottom;

so even if they're equal length primary pipes, the bends/angles account for some differences between banks.

[TAQuickness]

then there's the Coriolis effect to consider... Kicked my arse for a good long while.

[SSpdDmon]

then there's the Coriolis effect to consider...

say what? :nixweiss:

[joecar]

lol, affects the flux density... :D

[SSpdDmon]

Is that like the flux capacitor?

[ringram]

Yeah, but only kicks in during solar flares.