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Message: [QUOTE="907DAVE, post: 355212, member: 672"] Okay guys, I am going skip way ahead and start with the fun stuff. This is most people are scared of, timing! I am going to throw up a few examples of what not to do. These next few maps will be from a PMT1 split shot file. **Disclaimer** I do not claim to be a professional tuner so do don't take my words as gospel. If anyone feels I am incorrect or left something out, please say so. Here's what a stock base start of injection (SOI) map looks like. [ATTACH=full]88324[/ATTACH] The vertical numbers are degree's, bottom left is Mass Fuel Desired (MFD) and bottom right is RPM's. MFD is a calculation the PCM makes that is based off Accelerator Pedal Position (APP) and RPM. This a stock SOI Delay Map. [ATTACH=full]88325[/ATTACH] This map uses engine oil temp (EOT) on the bottom right and injection control pressure (ICP) rated in Mpa on the bottom left to decide what to do (advance SOI in milli seconds (MS)). This is why its unique, as it is based off time and not crank angle like the base map is. I believe the purpose of this map is to adjust for cold sluggish oil, but many tuners use it as a limiter or adder to keep timing low until EOT reaches normal operating temperature. This map can really get you into trouble if not treated properly. Now the ugly. Here is a Base SOI map that has been attributed to numerous engine failures. It is overlaying a stock map for effect. [ATTACH=full]88326[/ATTACH] And a SOI delay map that looks like this doesn't help any. [ATTACH=full]88327[/ATTACH] Lets do a quick calculation of the max commanded SOI. First we will look at the max MFD and RPM from the base map. It turns out to be 14 deg. advance, which necessarily is not too bad. Now if you look at the delay map in a similar situation its roughly 1.58 ms. I have a handy spreadsheet that takes all the work out of figuring crank angles from MS, if anyone would like to have it let me know. At 3400 RPM (WOT shift) 1.58 ms comes out to 32.2 degrees advance. Stack that base 14 deg. on top and you are at 46 deg. advance. Yummy. Discuss. [/QUOTE]