[Mike@N54Tuning.com]

I know there has been a lot of interest recently in comparing the output and performance of the JB4 when compared to the new kid on the block (COBB) so BMS went over to the dyno and did some testing, so I thought I would share the results with community as its very topical.

Hey guys,

Headed back to the dyno to retest the Stage2 maps. Since last round I've added CPE downpipes and an OEM N55 midpipe to the car. It's still running the stock intercooler and 135i muffler back, still on 93 octane, etc.

The main purpose was just to test the JB4 map 2 vs. the Cobb Stage2 map. But while it was strapped down for kicks I tested the Cobb Stage2+ map and did a few runs working on a JB4 map 6 to test some "more aggressive" type JB4 settings.

As last time I have tons of data to sort though but as a general rule the Cobb ran more boost, more fuel, and less advance compared to the JB4. The Stage2+ map is definitely much more aggressive with a peak of 18.5psi compared to JB4 map 2's peak of only 14.5psi, but the JB4 runs a lot more advance and is actually very close in terms of power output from 5000rpm+. The range you'll be operating in during a race.

The JB4 map 6 is just something I was playing around with. I was able to get the boost and advance close to where I wanted it but didn't have time to work on the fueling end. So for the moment it's just a work in progress. But, it was very competitive in terms of power output.