I had installed a used stock 420hp LS3 a customer's 68 Firebird. I had to do minimal work to the MAF to get it running properly.
From day one that engine made lifter noise and ended up spinning 2 rod bearings.
We agreed it was more cost effective to put a crate engine in and decided on a 495hp LS3 for just a few hundred dollars more than the lower hp version.
Well, I am not well versed in E38's (I know 0411 well).
My issues are around idle and cold start. Unfortunately I can not get the car to come to cold start idle without a little throttle so the log starts with me helping it with some pedal.
AFR starts of "ok" not perfect, but as it warms it is creeping leaner and leaner.
I believe I have all most if not all adaptive spark and throttle tables locked.
I'm not sure where to go from here.
I want to get this car back to the customer ASAP so he can enjoy summer in the convertible.