BMW 340i xdrive JB4 Map 3 question

zeeshawnabid · 11-27-2020, 09:33 PM

Hey,

I have a 2017 BMW 340i xdrive with the BMS intake and JB4.
I run 93 octane gas as well.

Am I able to run Map 3 with the JB4?
Heard I may need downpipes and would love to confirm.

Thanks

eritF30 · 11-28-2020, 08:34 AM

You can run map 3 without aftermarket downpipe.

Nickski06 · 11-30-2020, 08:03 AM

When I first installed the JB4 on mine, map 2 was smoother, but felt down a bit on power compared to the JB+ I had on it. Map 3 felt powerful, but a bit jerky and laggy and times. After a couple months it felt like the car adjusted and map 2 felt like stock, so I tried map 3 again. Now it felt much better, no more weird shifts or jerkiness. It didn’t feel as smooth as stock, but was pretty good. For the last month or so I decided to try adding a little E85 just to get the octane up for safety, about an E20 blend. I think the car feels even smoother now. Feels like stock but with way more power.

11-27-2020, 09:33 PM	#1
zeeshawnabid New Member 2 Rep 5 Posts Drives: BMW 340i xdrive Join Date: Nov 2020 Location: Minneapolis iTrader: (0)	BMW 340i xdrive JB4 Map 3 question Hey, I have a 2017 BMW 340i xdrive with the BMS intake and JB4. I run 93 octane gas as well. Am I able to run Map 3 with the JB4? Heard I may need downpipes and would love to confirm. Thanks
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11-28-2020, 08:34 AM	#2
eritF30 Enlisted Member 8 Rep 48 Posts Drives: 340i xdrive Join Date: Nov 2020 Location: new jersey iTrader: (0)	You can run map 3 without aftermarket downpipe.
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11-30-2020, 08:03 AM	#3
Nickski06 Private First Class 53 Rep 105 Posts Drives: 2016 340i M-Sport Join Date: Sep 2020 Location: Indiana iTrader: (0)	When I first installed the JB4 on mine, map 2 was smoother, but felt down a bit on power compared to the JB+ I had on it. Map 3 felt powerful, but a bit jerky and laggy and times. After a couple months it felt like the car adjusted and map 2 felt like stock, so I tried map 3 again. Now it felt much better, no more weird shifts or jerkiness. It didn’t feel as smooth as stock, but was pretty good. For the last month or so I decided to try adding a little E85 just to get the octane up for safety, about an E20 blend. I think the car feels even smoother now. Feels like stock but with way more power.
	Appreciate 0 Quote