Thanks for the input.

I got the same advice from a guy that rebuilt my motor for the suburban i have. he also said he could get the megasquirt 2 with a better starting point to start to tune.
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I have a 383 in a 78 chevy that I wanted to put EFI on it. I modified a LT1 intake manifold to work with it and got megasquirt to start the motor.

I bought a 1999 suburban with a bad motor and...