Quote Originally Posted by spfautsch View Post
With all the accessory equipment on the odd bank I felt like I was herding cats trying to get reliable temps with the IR gun. It was even a "fancy" one with a laser aperture indicator.
I've tried that several times. If i hold the gun upside down i can get upto 100Degrees C higher.

The balance test showed that 1, 2 & 3 are overall the weakest, with 1 showing nearly 20% lower #s than the strongest holes (5 & 8). I know 1 & 2 are usually weaker on smallblocks with this type of intake plenum. But doesn't #1 also has the smallest idle air feed hole? I have to assume GMs engineers did this for a valid reason, but wonder if making them all the same size would do any good.
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The Balance test also seems to vary from day to day.
The front cylinders are set to have more fuel and the rear less in the cylinders in the stock tune.
Drilling the manifold idle hole out makes no difference at all as far as i've seen, although the drillings on the Edelbrock LT4 manifold is a bit crap to start with.
Splits move around & seem to come & go on a whim.
Idle timing changes, I have seen affect the timing on the injector BPW which i would expect to increase the BLM splits. As the timing increases the bpw drops but more on one side than the other.

[QOUTE]I might have a touch of OCD so I take this statement as a challenge.
Me too. I want to know it's right.

I know what you're saying, and I've read posts where you mention disabling the part-throttle individual trims. When I was running speed density to tune VE I noticed my cell 16 split was always lean on the even bank by +15-20, but the adjoining part-throttle cells (5,6,8 & 9) always had the odd bank showing lean. I was starting to wonder if I had accidentally plugged the post-cat O2 sensor into the primary connector.
I suspect the Mac midlength headers for some of it.
The 02's seem to be sat in 1 pipe rather than reading an average in the collector so I think playing with the fueling doesn't really show up on the other 3 cylinders the same.

Strangely, after I buttoned up my VE tuning and turned the MAF back on with no other changes to the tune the splits all but disappeared. Cell 16 split is averaging 1, and the worst tip-in cells (5 & 8) are 6. I'm starting to wonder if I can't use the part throttle cylinder trims to try and tweak this out. With a sloppy cam like this you can use every ounce of torque you can develop in those low airflow ranges.

Whatever the case, I'm baffled as to where the split "disappeared" to.
Haven't got around to putting the MAF back in yet.
I went SD with some success but the wideband & narrowbands don't quite match up. Wideband ran really well but i felt was too rich.
The narrow bands feel a little light.
Since I've dropped the timing down loads again the car is much more relaxed than before.

If it's happy & it runs it will be fine.

HTH
Mitch