For those that have attempted this... Can I pick your brain?
I have a 2005 M3 with the MSS54HP. I did a conversion to a CSL Cone using a CSL style airbox, 288/280 cams, stepped headers, open exhaust, GM Map sensor, 93 octane, etc.
The main differences are: I am using the MSS54HP with no H-Bridge. Also, the engine was built with slightly higher 12.0:1 forged pistons. Other internals are stock.
I had been running a custom Alpha-N tune. But I have time on my hands and want to try for something better.
I am now running the modified 0401 CSL software for the non-CSL bootloader. I got it working with a combination of the BimmerGeeks Tools, MSSflasher, Binary Modification Tool, TunerPro, etc. Amazing tools.
Today I went for the first drive. It feels really good. But it has a pretty violent misfire under high load around 3000 and below. At 4000 up it pulls hard and feels smooth. On regular streets under partial load, it's fine. But on the highway attempting a pull in a higher gear, it misfires.
I interpret this as the DME cutting the ignition because it senses something wrong. If it were knock, I would expect it would just retard the timing. It seems to do that well elsewhere. If it were fuel, I would not expect it to feel like that. I know there are about 50 compensation maps in there. But I need an idea where to investigate.
I have an Innovate LM2 logger. But I need to replace the O2 sensor before I can do some logging.
Given I am not the first person to try this, can anyone who has tried give me hint were to look? Has anyone encountered this?
Thanks
I have a 2005 M3 with the MSS54HP. I did a conversion to a CSL Cone using a CSL style airbox, 288/280 cams, stepped headers, open exhaust, GM Map sensor, 93 octane, etc.
The main differences are: I am using the MSS54HP with no H-Bridge. Also, the engine was built with slightly higher 12.0:1 forged pistons. Other internals are stock.
I had been running a custom Alpha-N tune. But I have time on my hands and want to try for something better.
I am now running the modified 0401 CSL software for the non-CSL bootloader. I got it working with a combination of the BimmerGeeks Tools, MSSflasher, Binary Modification Tool, TunerPro, etc. Amazing tools.
Today I went for the first drive. It feels really good. But it has a pretty violent misfire under high load around 3000 and below. At 4000 up it pulls hard and feels smooth. On regular streets under partial load, it's fine. But on the highway attempting a pull in a higher gear, it misfires.
I interpret this as the DME cutting the ignition because it senses something wrong. If it were knock, I would expect it would just retard the timing. It seems to do that well elsewhere. If it were fuel, I would not expect it to feel like that. I know there are about 50 compensation maps in there. But I need an idea where to investigate.
I have an Innovate LM2 logger. But I need to replace the O2 sensor before I can do some logging.
Given I am not the first person to try this, can anyone who has tried give me hint were to look? Has anyone encountered this?
Thanks
Comment