BMW B58 BM3 Tuning Guide – Info & Horsepower Gains
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.
Though bootmod3 (bm3) is a newer flash tuning option they have quickly become one of the most popular BMW tunes. Pro Tuning Freaks bm3 offers a web interface and mobile apps for simple flash tuning. Bootmod3 also offers a handful of off-the-shelf flash maps loaded with cool features. If you’re in the market for a B58 tune the bm3 should definitely be in the discussion. In this guide, we will cover B58 bm3 tunes, maps, supporting mods, horsepower gains and more.
About bm3 Flash Tunes
Bm3 offers off-the-shelf (OTS) flash tunes for the BMW B58 engine. Their OTS tunes are extensively tested and highly proven on the B58 platform. Additionally, bm3 flash tunes are easy to install and affordable. A quick breakdown of costs:
- $595 software license
- $50 map pack
The software license must be purchased in order to flash any bm3 B58 tunes. With the license is purchase you receive 1 OTS map of your choice. For an additional $50 bm3 offers a map pack bundle which includes ALL OTS maps available. If you’re planning to simply flash one tune and go then the software license and 1 map will suffice. However, we recommend buying the map pack bundle up-front or at least expecting to purchase it down the road.
Bootmod3 B58 Maps:
- Stage 1. (91 octane, 93 octane, E30)
- Stage 2. (91 octane, 93 octane, E30, racegas)
- Stage 2+ (91 octane, 93 octane, E30)
Throughout the remainder of this post we will discuss the above B58 bm3 stages and recommended supporting mods for each. We will also provide rough horsepower estimates for each stage dependent upon fueling.
*We recommend replacing B58 spark plugs prior to flashing bm3 tunes, especially if your spark plugs are 25,000+ miles old.
**All B58 horsepower numbers are estimates. We’re also basing the horsepower off the recommended supporting mods we state. Therefore, extra mods we don’t mention (such as meth injection) may result in extra power.
B58 bm3 Stage 1 HP Gains & Mods
Mods Recommended: Intake
Horsepower gains from the intake on a conservative stage 1 tune is questionable. The B58 stock airbox is pretty efficient. However, you may pick up a few extra horsepower from the addition of an intake. If not for the small power gains, we’re including the intake since we love it for sounds alone.
Anyways, bootmod3 stage 1 tunes are the least aggressive OTS option from bm3. We recommend the intake, however no mods are absolutely required. You can simply flash these bm3 stage 1 tunes and go.
Bm3 Stage 1 Horsepower
91 octane: 360-380whp
93 octane: 370-390whp
Expect B58 bm3 stage 1 horsepower figures in the ballpark of 360-410whp. As indicated with the above hp numbers, power increases with fuel quality. 91 octane is poor fueling, especially ACN91 (AZ, CA, NV). 93 octane is standard in some states and picks up about 10-20whp more than 91 octane. Finally, those with access to E85 fueling – for an E30 mix – will likely show the best results. If E85 is available in your area we highly recommend E30 fueling. Anyways, ~400whp is pretty darn impressive on a conservative stage 1 tune.
B58 bm3 Stage 2 HP Gains & Mods
Mods Recommended: Intake + Catless DP
Bm3 stage 2 tunes provide a decept bump when compared to stage 1; the tunes are a bit more aggressive. All else constant, stage 2 maps will run a couple PSI more than the stage 1 maps. However, a catless downpipe is going to provide a decent chunk of the benefits. Not only does it provide a good bump in power, but a catless downpipe also helps reduce turbo lag.
Bm3 Stage 2 Horsepower
91 octane: 390-410whp
93 octane: 400-420whp
Race gas: 410-430whp
Bm3 B58 stage 2 tunes come in with horsepower around 390-440whp. Again, expect higher boost targets and power on better fuels. Again, we highly recommend opting for a catless DP with this stage. Reducing back-pressure will make the turbos job a bit easier. You’ll also appreciate the quicker spool and extra power.
B58 bm3 Stage 2+ HP Gains & Mods
Mods Recommended: Intake + Catless DP + HPFP
Finally, we’re moving onto the most aggressive OTS option from bootmod3. Stage 2+ bm3 tunes roll in some extra boost in order to gain power over the stage 2 options. However, stage 2+ tunes aren’t the most common. Bm3 states these B58 tunes require an upgraded HPFP (or the pump from the B58TU). If you’re dropping money on an upgraded HPFP chances are a custom tune is going to be your best bet. However, these bm3 stage 2+ are definitely capable of some very impressive performance.
Bm3 Stage 2+ Horsepower
91 octane: 410-430whp
93 octane: 420-440whp
Horsepower comes in around 410-470whp depending on fueling. These are very promising numbers. There’s no question the B58 turbo can move some air. However, if you’re looking to push your B58 this far you may be best suited to custom tuning. Custom tuned B58’s with meth injection and E30 are capable of nearing or surpassing 500whp. Bm3 allows the ability to flash custom tunes, however custom tuning would come at an extra cost.
Time will tell if the B58 stock turbo can be pushed much further. However, consider turbo longevity if you’re really looking to push ~20psi and 470+whp. Nonetheless, the B58 stock turbo numbers are already matching the twin turbo N54. Additionally, the B58 stock turbo holds the power better up top.
B58 Bootmod3 Flash Tune Summary
There is no question the stock B58 leaves a ton of power and torque on the table. As such, many look to tunes and simple bolt-ons to take the B58 to the next level. Bootmod3 is a relatively new offering in the BMW OTS flash tuning world. However, they quickly became one of – if not – the most popular B58 flash tunes. Bm3 offers stage 1, 2, and 2+ OTS tunes for the B58 engine.
Stage 1 tunes are basic, entry level tunes with no other mods required – simply flash and go. However, we recommend opting for an upgraded intake. Moving onto stage 2 tunes it is recommended to run an upgraded B58 intake and downpipe. Finally, bm3 stage 2+ tunes require an upgraded HPFP. However, with the assistance of additional fuel flow these tunes are capable of 450+whp with E30 fuel. Very impressive numbers for an OTS tune.
Anyone looking to push any further may consider meth injection and a custom tune. A few B58’s already eclipsed 500whp on the stock turbo and we suspect that will become a more common goal. However, turbo longevity at that power and boost is still a question mark. Nonetheless, the B58 tuning capabilities are already amazing and look no further than bm3 to help meet your tuning needs.
Can I run a 200 cell high flow downpipe with stage 2 or do I NEED the catless?
you can run the high flow and everything will be fine
Looking into upgraded my hpfp to a TU. At this point with 93ron I can expect to push between 420-440whp but if I go custom I can get more out of it?