Tuning question

[91dime]

Im trying to help a guy out with a tune for his truck and need advice on a starter bin. I haven't touched this stuff in a couple years and im pretty rusty on it. He says its a z71 350 bored 40 over with an RV type cam, i can post specs if needed. He has a BJYL prom running the truck at the moment. Advice on where to start?

[Stokes1114]

Is BJYL the stock bin that came in truck? If so definitely start with that and go straight to the VE tables. After you get the fueling table close, jump to spark and add timing conservatively and watch for knock counts/retard.

[Six_Shooter]

I agree, start with the current or stock BIN and tune from that.

[91dime]

Actually now that I think about it, he said he replaced the computer and the current computer running it is a 7427 with the bjyl prom. Its a 93 and I'm not sure what computer came out of it.

[Stokes1114]

If its a 93 and has a 4L60e it came with a 16168625 and ran $E6 code. The computer and code is pretty much identical to 16197427 $OD. I have a 93 and Im currently running $OD with a swapped 7427. It runs the same as did with the factory pcm and $E6. I would def keep using BJYL and go from there.