[KnighTT]

I am in the break in side of an entire build up of my e92 335is.

For break in, is MHD flashed with stage 0 a good idea or flash it back to stock until a custom tune is put in place? A custom tune is the plan but while I am just breaking in the engine under stock conditions, should I omit MHD or is stage 0 best to keep some CEL at bay? DPs, 3.5tmap, etc.

Some details.

Built block, stg2+ turbos, intakes, outlets, full external PCV system, etc etc.

- I've flashed MHD and Stge 0 so I can check catless DP's and 3.5TMAP.
- I've done a 20min break in(in the garage) from 2-3k RPM.
- Oil change

Now I'm in the phase where I'd like to get out and drive it for next phase break in.

Idle is terrible. Engine is loud and there is enough noises to make it difficult to know if something is wrong. Maybe just the stock flash would ease out the harshness?

Let me know what you think.

[BSM n54iS]

I'm no expert on rebuilding etc just my .02 I would prefer myself to keep everything as stock as possible for first firing up and break in periods. Then after that start 1 by 1 changing either software or the 3.5 and so on. Make sure everything runs as supposed to first.

[KnighTT]

This is a solid point. I just flashed it back to stock and we'll see how the run up goes now. Even with the stock map, I have a feeling I'm going to be troubleshooting what feels like a vacuum problem. When you replace EVERYTHING, that doesn't mean it's smooth on the other end.

[KnighTT]

I got it fired back up but I almost immediately get an engine malfunction due to my 3.5TMAP. I'll have to drop in the original and rewire it. I'll see if that clears it up.

I'll give it another try afterwards tonight.

[iqraceworks]

You want to run a tune that best matches the mods you have.....and with bigger turbos, you probably don't want a stock tune.

Breakin is all about heat cycles on the motor, taking things easy, varying the rpms, and not putting a bunch of power to it for a couple hundred miles until the rings get fully seated in. You do that with your foot..the tune isn't going to affect that.

For the 3.5tmap..just check the box in MHD and be done with it.

[rjahl]

Originally Posted by iqraceworks

You want to run a tune that best matches the mods you have.....and with bigger turbos, you probably don't want a stock tune.

Breakin is all about heat cycles on the motor, taking things easy, varying the rpms, and not putting a bunch of power to it for a couple hundred miles until the rings get fully seated in. You do that with your foot..the tune isn't going to affect that.

For the 3.5tmap..just check the box in MHD and be done with it.

Agreed , how did we ever manage to brake-in motors before had computers?🤔

Process was even in car's owners manual.