[randomserious]

what mods are a must for otherwise stock m340i when going for a stage2 tune to keep it reliable? any optional mods that will amplify power?

[GA/\/\/\/\A_CT]

Downpipe is pretty mandatory

You may want to look at IAT gauges, or cooling mods like larger heat exchanger or intercooler; especially if you plan to drive aggressively for extended periods.

[randomserious]

Originally Posted by GA/\/\/\/\A_CT

Downpipe is pretty mandatory

You may want to look at IAT gauges, or cooling mods like larger heat exchanger or intercooler; especially if you plan to drive aggressively for extended periods.

I don't want catless and not looking to make my car louder, does something like a VRSF Catted downpipe work? would like to keep cost below $500

[jpowers36]

You’ll throw a CEL with that one. Other owners have reported it. Any aftermarket downpipe will make it louder.

Active Autowerke is the best option for catted downpipe. No CEL guarantee and I’ve yet to see anyone get one. MST has one but some recent cases came up with it throwing a CEL.

I love my AA downpipe. Got a great deal on a barely used one. Keep an eye out on in the classifieds.

[GA/\/\/\/\A_CT]

I have AA catted downpipe, too. It’s the gold standard for this mod.

[jpowers36]

Originally Posted by GA/\/\/\/\A_CT

I have AA catted downpipe, too. It’s the gold standard for this mod.

100%. Gotta pay to play.

[RTPenland]

Originally Posted by bray

not looking to make my car louder

Do not change the downpipe then, even a high flow catted aftermarket DP will make your stock exhaust nearly as loud as an aftermarket exhaust with stock DP in place. The change in sound volume is significant.

Based on everything you shared I would simply flash and enjoy the car, you will be just fine

[Jnasratyar]

Originally Posted by bray

what mods are a must for otherwise stock m340i when going for a stage2 tune to keep it reliable? any optional mods that will amplify power?

You need a aftermarket downpipe to run stage 2, without your limited to stage 1. You can upgrade your spark plugs as a precautionary measure, but for stage 1 stocks will do just fine. If your worried about the cel from the downpipe (you shouldn’t be) if your tuned you can simply disable cat monitoring and there will be no cel regardless of what downpipe yu run.

[randomserious]

Originally Posted by RTPenland

Do not change the downpipe then, even a high flow catted aftermarket DP will make your stock exhaust nearly as loud as an aftermarket exhaust with stock DP in place. The change in sound volume is significant.

Based on everything you shared I would simply flash and enjoy the car, you will be just fine

too late AA catted downpipe on the way. what i was trying to say is if i have two options i'll pick the quieter one. i do like burbles, though, but just upping the volume i don't need.

[RTPenland]

Originally Posted by bray

too late AA catted downpipe on the way. what i was trying to say is if i have two options i'll pick the quieter one. i do like burbles, though, but just upping the volume i don't need.

cool, looking forward to your feedback. Loved my catted DP but it was certainly louder (but to me in a good way) AA mighty fine product