Reading Cobb logs

[Mikey135]

I have almost no experience with reading these logs and understanding exactly what is going on. I am hoping you all might be able to educate me a little bit on what I need to look for. I am pulling all the info that Cobb suggests. In a few pulls I get some timming correction ( only ever in 1 cyl at a time) I hve read thatanything under 3.38 isn't to much to worry about. In onepull I hit-3.38 in cyl 4 and in another pull I hit -3.75 in cyl 1. how bad is that? What other numbers are important to look at and what are ranges I would want them to be in? Basically any info on exactly what to look for and be worried about is greatly appreciated.

[brusk]

1. Find a safe place to log and try to make runs as long as you can while being safe. Whether that's a full 3rd gear pull or maybe a partial 3rd and then into 4th to get as much load and heat on the engine as you can.
2. It's usually a good idea to discard the data that isn't during WOT Accel Ped. Pos 99.61 (whatever yours might be) as non WOT logs can have normal timing corrections that have nothing to do with tuning.
3. Next you want to look at the request load and actual load as well as the request boost and the boost to make sure you aren't going over your requested numbers. If you are the DME will close the throttle and you will get bad data to go off of.
4. Look at the Cylinder timing corrections. If you only have a few cylinders complaining that is ok. Advance timing a little at a time until all cylinders have just a little timing correction. From there you can either back off until all cylinders are clean (if possible) or you can back off the timing until most of the cylinders are running clean and only have minimal corrections.

Keep in mind that the DME is very good at keeping things safe and from what I see you can run pretty good advance and the DME will pull back what it needs. In a typical tuning fashion you don't want that but take the JB4 for example that only has access to read cylinder 1 and typically does nothing with the timing and lets the DME pull as much timing back that's needed and people swear by it.

[Mikey135]

Thanks for the help.