B48 Bootmod3 Tuning Guide

BMW B48 BM3 Tuning Guide – Info & Horsepower Gains

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Meet Zach

Zach is a BMW enthusiast with a passion for performance. With over 10 years of experience modifying and performing DIY work on BMWs, he’s developed a deep understanding of virtually every BMW engine. He’s also the proud owner of a 600whp N54 with upgraded twin turbos and an E30 325i drift car and has a particular affinity for the S58 engine. Zach is highly knowledgeable about all things BMW, but his expertise in tuning and performance mods sets him apart. His experience as an enthusiast, combined with his technical knowledge, makes him an essential resource for anyone looking to improve the performance of their BMW.

Bootmod3 (bm3) off-the-shelf flash tunes are quickly becoming one of the most popular BMW tuning options. The bm3 tune – from Pro Tuning Freaks – uses a mobile app and web interface for simple flash tuning. Their B48 tunes also offer a good selection of OTS flash maps loaded with great features. B48 owners in the market for a tune should definitely consider bm3. In this guide, we will discuss B48 bm3 tunes, maps, supporting mods, power gains, and more.


About B48 bm3 Flash Tunes

Bm3 offers off-the-shelf (OTS) flash tunes for the BMW B48 engine. These tunes are extensively tested and highly proven on the newer B series engines. It’s also easy to install, reasonably priced, and loaded with great features. Just a few of the reasons bm3 tunes are so popular on the B48. The bootmod3 costs for the B48 are:

  • $595 flash license
  • $50 map pack

The flash license is essentially purchasing the basic software to flash your BMW. However, the license also includes 1 OTS map of your choice. Those going this route should select the map that best suits their supporting mods and goals. Bm3 also offers a map pack for $50 which includes ALL off-the-shelf maps available for the B48. We recommend purchasing the map pack if you intend to continue adding bolt-ons in the future. It’s also a great option for those who want the flexibility of switching maps. You can also just get the license and one map up-front and purchase the map pack down the road.

Bootmod3 B48 Flash Maps

The B48 OTS maps include the following:

  • Stage 1
  • Stage 2

Currently, there are only two stages for the B48 engine. Each stage has different maps within dependent upon fueling. These include 91 octane, 93 octane, and E30. Per Pro Tuning Freaks website they are also working on releasing race gas maps. In the remainder of this post we will discuss the two B48 bm3 stages and recommend supporting mods for each. Additionally, we’ll provide horsepower estimates for each stage and fueling option. A few quick notes prior to diving into the fun stuff.

*We highly recommend replacing your B48 spark plugs prior to flashing tunes. This is especially true if your spark plugs are 25,000+ miles old. You may also consider replacing ignition coils. However, old spark plugs are usually the main culprit of misfires after tuning.

B48 Spark Plugs

B48 Ignition Coils

**The B48 horsepower numbers we mention below are estimates. Additionally, we’re basing the power gains off the recommended supporting mods we reference. Mods we don’t mention may result in additional power.

B48 bm3 Stage 1 HP Gains & Mods

Mods Recommended: Intake

Power gains from a B48 intake could be debated, especially on a modest tune like the bm3 stage 1. The stock airbox holds up well on the B48. Although, an aftermarket intake may help pick up a few extra horsepower. We love the sound of open intakes, so we’re including an intake for the sounds alone – if not for the small potential power gains.

Bootmod3 B48 stage 1 tunes do not have any supporting mod requirements at all. You can simply flash these stage 1 maps and go. They’re pretty conservative tunes, but pick up respectable power gains.

Bm3 Stage 1 Horsepower

91 octane: 245-255whp

93 octane: 250-260whp

E30: 255-265whp

B48 30i models typically dyno in the ballpark of 225-230whp in stock form. As evidenced by the bm3 stage 1 horsepower it’s a pretty modest tune. Dependent upon fueling, you might only pick up about 15-30whp over stock. However, 20i models will see much more impressive power gains as they have a lower starting point. Power for 20i and 30i B48 models will end up in a similar ballpark.

Again, the stage 1 tune is a conservative option. It will be interesting to see if these tunes become a bit more aggressive in the future. It’s obviously still early for the B48 and there may be lingering concerns about pushing things too far. If you’re not excited for the stage 1 tunes then you may consider upgrading your downpipe and opting for the stage 2 options.

B48 bm3 Stage 2 HP Gains & Mods

Mods Recommended: Intake + DP

The stage 2 B48 tunes are more aggressive overall and target higher boost. Additionally, a high-flow catted or catless downpipe is highly recommended. An upgraded B48 downpipe will help reduce back-pressure and make the turbos job easier. A downpipe alone provides pretty solid power gains of roughly 10-20whp. It will also help the turbo spool faster, which the butt-dyno will approve of.

Bm3 Stage 2 Horsepower

91 octane: 265-275whp

93 octane: 275-285whp

E30: 285-295whp

B48 Bm3 Dyno

Expected power with the bm3 stage 2 tune comes in around 265-295whp. Higher octane fuels and E30 will provide bigger benefits on this stage as compared to stage 1. These are pretty solid gains overall for basic mods. Again, it will be interesting to see if these stages become more aggressive in the future. Maybe bm3 will also roll out stage 2+ maps in the future. The N20 didn’t earn a reputation for being a strong motor so there may be some lingering concerns with the B48, too. It should be a stronger engine, but it will take time and more modded B48’s to see how much further OTS tunes can go.

BMW B48 bm3 Flash Tunes Summary

Bootmod3 offers some excellent off-the-shelf flash tuning options for the B46 and B48 engines. Currently, bm3 offers stage 1 and stage 2 tunes for 91, 93, and E30 fueling. They’re also working on some race gas maps. Stage 1 tunes offer considerable power gains for 20i models with a lower starting point. However, 30i owners may find the stage 1 power gains underwhelming.

Stage 2 OTS maps offer power up to nearly 300whp with an upgraded downpipe and intake only. The B48 likely has a bit more left in it and there may be some more aggressive OTS options in the future. For now, those looking for additional power may look towards meth injection or custom bm3 tuning options.

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  1. I want to confirm whether the 325li in China can be flashed the stage 1, My car has remote starting engine function, thank you

  2. Do they support 95 or 98 octance on stage 1 ? in norway the standard is 95 octane but we can find 98 Octane fuel some places but its more expensive so I’m asking if 95 fuel is safe.

  3. I.have a B48B20A (320i M pack) with E25 by factory (Brazil fueling spec).
    It s a stage 1 flash, very conservative, and I m using 104 RON Premium gasoline. No problem, att all. Logs are perfect.
    Boost = 17psi (stock 10psi)
    Power = 250whp
    Tork = 420Nm (stock 300)

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