S55 K&N, Maximum PSI, and BMS intake testing on 6MT BMW F80 M3 with JB4 tune, Status Gruppe downpipes, and RPI exhaust - 538 rwhp

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Early this year BimmerBoost posted an article regarding how restrictive the S55 intake system in the F80 M3 and F82 M4 is. That article was focused on gains Maximum PSI claimed for their front mount air intake system. Well, now we have more testing of the S55 air intake system in various configurations.

Here are the specs on the test car a 6MT F80 M3:

6MT, 4th gear dyno runs
JB4 on map 2
93 and E85 blend
Status Gruppe downpipes
RPI exhaust

Now let's get to the test results:

The car was brought to us with the fuel blend already in it. I would have preferred straight 93, but we worked with what we had. We installed oem intakes and filters and drove the car around so it could adapt a bit. We then strapped it down and began filming/testing. The test was done on our dynojet. We made all of the pulls on map 2, fans on, hood closed, 4th gear, starting from 2k rpm. There was a ~5 min period between each run, and the car was running except when I swapped the different parts.

3 runs - OEM intakes/filters/carbon filters
6 runs - K&N drop-in filters, carbon filters removed
3 runs - BMS intakes
7 runs - Maximum PSI intakes
1 run - Maximum PSI intakes, map 7

It is interesting to note the K&N filter makes similar peak power to the BMS S55 intake but the BMS intake makes more torque. All of these options are picking up power and torque on the stock intake and filter though.

It is interesting to note the bottom graph is from a different Dynojet and it reads higher than the Maximum PSI Dynojet.

Regardless, with the Maximum PSI front mount intake system and a more aggressive JB4 map it is possible to go well over 500 wheel horsepower on a blend of 93 and E85. It would have been nice to see 93 octane only results but the fuel the car had is the fuel the car had.

What we learn is the S55 intake can be improved considerably.