305 TBI Conversion - Need Tuning Help

[halljam70]

Long story short. 86 1/2 ton chevy pickup. Swapped from carb to TBI setup. Engine has 416 casting heads, factory TBI intake, 204/214 @050, 112 lc cam, 350 injectors (305 injectors were too lean), 7747 computer w/ zif socket. My ve tables are all over the place, and when I graph, it looks like a mountain range. Any suggestions would be appreciated.


One log from this weekend attached along with the program loaded on the chip. Lockout kicking in and out was due to a miss-wire (fixed today).

[Fast355]

Long story short. 86 1/2 ton chevy pickup. Swapped from carb to TBI setup. Engine has 416 casting heads, factory TBI intake, 204/214 @050, 112 lc cam, 350 injectors (305 injectors were too lean), 7747 computer w/ zif socket. My ve tables are all over the place, and when I graph, it looks like a mountain range. Any suggestions would be appreciated.


One log from this weekend attached along with the program loaded on the chip. Lockout kicking in and out was due to a miss-wire (fixed today).

I may still have a .BIN file kicking around that can help you. I had a 1983 G20 van with a practically identical cam and 14022601 heads that I converted to TBI and used the spark map out of the E4ME feedback Q-Jet computer. I had the TBI system from a 1992 G20 350 Van on it but mostly used the 87-91 7747 ECM.

[halljam70]

Thanks Fast. I've read a lot of your posts from this site and over on 3rdgen. Really appreciate the wealth of knowledge you've posted over the years.