BM3 + JB4 meth - N54Tech.com

jamesmurray · **BM3 + JB4 meth -** 07-07-2020, 01:59 PM

Hi, I've been running a stage 2 BM3 flash on my M240i for the past few months and in the never ending quest for more speed I thought I'd best put my old BMS meth kit to good use (previously fitted to my N54 335). I bought a used JB4 with EWG and have just fitted it today. I would like to run the JB4 either as a standalone meth controller or use map 7 if possible with a small boost additive.

I've been reading through many of the posts on the forum, but I'm not entirely clear of the settings I would need to run for either setup. Could anybody help with the most up-to-date settings that I could use?

I've added a Map 0 log (traction issues in 3rd!) for reference before I start installing the meth kit.

Thanks

james

Terry @ BMS · 07-07-2020, 05:50 PM

I'd suggest using map7 so boost is increased over the flash target as a function of meth flow. Start with a 65 additive and we can evaluate from there!

jamesmurray · 07-08-2020, 04:46 AM

Thanks for the reply Terry. I guess I leave both meth safety and trigger set to 0?

Terry @ BMS · 07-09-2020, 04:38 PM

Yes to start, the default settings

jamesmurray · 07-20-2020, 01:47 PM

So after a bit of a delay, I've managed to install the meth system into the car. For initial testing I'm using a cm7 nozzle (but I've got additional nozzles to upgrade to) with a 65 additive. It looks like that's too high from the logs as it's causing some timing issues and the hpfp to dip. Shall I lower the additive and increase to dual cm7 nozzles? Are there any other adjustments I need to make? Also it seems that the meth flow is dropping over the course of a pull. The tank is a little low so it may be that.

Thanks for all of the help so far.

James

Terry @ BMS · 07-20-2020, 03:24 PM

I'd try getting the meth levels up with dual nozzles and/or a stronger mix to evaluate.

jamesmurray · 07-21-2020, 06:12 AM

Thanks for the help Terry. I've fitted the extra nozzle so I'm now running dual cm7's, although I think there might be some air in the line as it's still falling off up top. Is there a way to bleed the air out other than using the purge button? Can I use the gas pedal method like in the n54's?

Here's the log from earlier, I started with a 45add and then went up to 55 towards the end of the log. Traction is now becoming a problem in 3rd, so it's time for better tires!

Thanks

James

Terry @ BMS · 07-21-2020, 02:06 PM

Looks generally good to me here. Anything over 60 on meth flow is full flow so not too bad up top.

jamesmurray · 07-21-2020, 02:41 PM

That's good to hear Terry, thanks for your help.

James