lets start off with a little about my setup. its a 92 k1500, 350 tbi with vortec heads and rpm dual plane intake, i have a comp XE256 cam and midlength headers. it had a 700r4 with a 7747 ecm for awile, and it ran its butt off. i could hammer it and i would just smoke the tires. when my transmission went up i put in a 4l60E and a 7427 pcm. ever since that swap ive had no power. no matter what i do. ive tried more timing, less timing it doesnt help. my WBO2 reads 11.6 on the guage and 12.5 in tunerpro. im not sure wich one is right. if i lean it out i get knock counts. im really lost now. any suggestions?

BTW it has a stock tbi with tbi mods and 24psi on 350 injectors. i have a 454 tbi on the way with 90 lb/hr injectors but im sure that isnt the solution to my problem

 

Off the top of my head, check the data log and see wha thte spark timing is doing. It may be that it isn't as much as it should be. There is torque management routines that will reduce the SA.

Another item is cat-con protection. That can cause the engine to run rich as it tries to protect the cat. Can set the two temperature thresholds high to disable the protection logic.

RBob.

 

thanks Rbob i have zeroed out the TQ management already. my spark timing reads 4 deg less in the logs. (4 deg initial advance). i havnt messed with CAT CON, but i will take a look. im just horrified to add so much timing. ive been running it at 29 deg at WOT with success but im afraid to add anymore. mabe i will