Just dropped a new LSX 454 crate engine into my 62 vette restomod. Its stock with LS7 intake/injectors. It has headers. Using E38 ECM with LS7 tune and after bumping cranking airflow and idle airflow and bumping spark to 16 from 13, it starts and idles reasonably well at 900 rpm. Using a card style MAF and all other stock sensors.
Does anyone have a tune for the LSX 454? I didn't see one in tune repository.
It presently undershoots idle, on coastdown mostly, sometimes stalling. There is also an off idle stumble. LTFTs are close to zero
I'll get it dyno tuned at some point.

LSX_05_28_16_0000.ctzLSX_05_28_16_0000.ctz
Thanks very much!

LSX454 TECH SPEC

Cam:
Valve Lift (in.):
0.648 intake / 0.648 exhaust
Camshaft Duration (@.050 in.):
236