spark tuning

[deepblack ss]

Going to be switching to e85 and was wondering if anyone could supply a method for adding in spark. Should I add spark everywhere? only certain parts of the table? If someone could outline a good process for me it would be much appreciated.

[CarsonTech]

MBT tuning on the dyno is the only correct way.

If you don't have access to a dyno, you could perform the following, potentially damaging, method... Increase timing in the areas that you are at when a WOT, unitl you see KR kick in, then decrease the spark in that cell a degree or two, or more fueling to add ignition lead. This is not a great method, sometimes you can overshoot MBT way before you reach any knock, which can be a waste. But if you don't have a dyno, I am not sure of any mothods besides these

[CarsonTech]

Oh, and don't forget to read the plugs after you make a pull. Make sure you at gapped right and have good plugs as well.

[InfraRedline]

On E85 you will not see knock so dont keep raising the timing in hopes to see KR then back it down. It is a great method for pump gas but you will start wasting your rod bearings after a certain point of timing on E85. What car is this on? I am going to assume an lsj judging by your name. If thats the case dont go over 25* or so in the WOT region of your table, and ramp it up to 25, dont just flatline the table

[CarsonTech]

Good point. Thats why the non-dyno method sucks if your not used tuning spark with E85.

[roderick]

max a lsj should run is 25 degrees timing.

[deepblack ss]

Thanks for all your help roderick ; )