When you guys change the spark tables and VE tables, do you tend to change the whole table the same amount (i.e. +/- every value the same amount) or do you change the actual pattern of the graphs for these tables? Basically what I'm asking is does GM have a good pattern to follow as far as the load vs. rpm graphs and they just made them conservative, or does the pattern need to be altered also? I'm probably going to do full exhaust on my TPI 305 as well as open up the air boxes (already have K&N's) and probably an air foil. I want to tweak the computer to optimize it for these changes and learn about prom burning for when my 385 is done. Since I'm not changing the cam or even the TPI parts themselves I assume I could just take the patterns already in the ECM and make them a little more aggressive.

Also, what's the name of the BIN for a '90 TPI 305? I don't have the G92 package, whence the smaller cam, but I don't think that really matters right?

Thanks.

 

Come on guys, need a little help here. Can you also tell me the file name for a BIN of a stock motor, then one that's been modified for that same motor so I can get a better idea of how changes effect performance?

 

When I started with stock software for my 355 with intake and exhaust mods, I started by modding the whole VE table for the first few tuning sessions. After about 3 of these, I started tuning individual RPM/KPA cells as the ALDL data showed they needed. Graphing my VE and spark tables now versus the stock settings shows very little resemblance, either in the individual data points or in the overall curves.

You'll need to get ALDL data on your engine, no way you can mathematically calculate the changes needed without seeing exactly what's happening in the BLM and knock retard data.

Answering the stock bin part of your question, you have a few options depending on what trans (manual or auto) you're running:

AXYB is a 1990 305 with manual trans
AXXD and AXXC are a 1992 305 " " and different gear ratios

There's a more complete list of software broadcast codes (BCCs) at https://www.thirdgen.org/newdesign/faq/thirdgen.shtml

 

Thanks Kevin. Those were they type of answers I was looking for. Sorry I forgot to include manual tranny. Thanks again.