Drop in filters- Loss of power?

[Tommy L Garage]

Originally Posted by MNMWMWMN

Can you share a direct link to the dyno results?

SUre - here you go. In the video I forgot that my car had K&N filters.
So essentially, the first runs compare stock for stock, where one has a K&N drop in (mine - manual) and the other one does not....but has a DP on a stock tune. The results are pretty interesting

[6SPD GOD]

Originally Posted by Tommy L Garage

SUre - here you go. In the video I forgot that my car had K&N filters.
So essentially, the first runs compare stock for stock, where one has a K&N drop in (mine - manual) and the other one does not....but has a DP on a stock tune. The results are pretty interesting

Unfortunately, you're comparing 2 different vehicles. If you have the chance, it would be very interesting to compare the difference on HP/TQ on the same vehicle, same dyno, same day, without even hooking it off the dyno. Even a slight change on the securing point could eliminate the constant.

[DanMpower]

Originally Posted by MNMWMWMN

Unfortunately, you're comparing 2 different vehicles. If you have the chance, it would be very interesting to compare the difference on HP/TQ on the same vehicle, same dyno, same day, without even hooking it off the dyno. Even a slight change on the securing point could eliminate the constant.

Also, his car is manual and the other car is DCT. Too many variables.

[6SPD GOD]

Originally Posted by DanIAM3

Also, his car is manual and the other car is DCT. Too many variables.

Correct.

We need

- Same vehicle
- Same dyno
- Same day
- Do not unstrap/unsecure the vehicle
- Continuous Runs


The filters should be the only variable in order to obtain consistent and significant results.

Other than that we are comparing oranges and apples.

[Tommy L Garage]

Originally Posted by MNMWMWMN

Correct.

We need

- Same vehicle
- Same dyno
- Same day
- Do not unstrap/unsecure the vehicle
- Continuous Runs


The filters should be the only variable in order to obtain consistent and significant results.

Other than that we are comparing oranges and apples.

That's the plan one day

[drgmt]

Originally Posted by MNMWMWMN

Correct.

We need

- Same vehicle
- Same dyno
- Same day
- Do not unstrap/unsecure the vehicle
- Continuous Runs


The filters should be the only variable in order to obtain consistent and significant results.

Other than that we are comparing oranges and apples.

From a scientific perspective this is true. However, it's difficult to extrapolate a stock car data to a tuned one with other mods.

[Dr._Who]

Hey,

Maybe it's just (placebo) me, but when I replaced my air filters with the "BMC's", my car got louder!


Cheers!

[overlook637]

Human perception. The drop in filters are as quiet as the oem filter. So when you go full throttle you do not hear the change in sound until higher rpms. So you assume it wasn't making as much power, based on the perception of sound changes.

I highly doubt the power changes + or - were large enough for anybody to accurately measure based on seat of the pants.

Perception.

[tom @ eas]

Originally Posted by Dr._Who

Hey,

Maybe it's just (placebo) me, but when I replaced my air filters with the "BMC's", my car got louder!


Cheers!

Not placebo. The combination of adding BMC filters and removing the charcoal liners will make a slight increase in intake noise.

However, adding one of the many intakes on the market will make the car sound like its having an asthma attack.

[CigarPundit]

I responded to the same question in another thread and posted my before and after dynos comparing before and after BMC on an otherwise bone stock 2018 F80. See response 36. No loss anywhere, and certainly nothing that could be described as a substantial loss in low end that could be felt on a butt dyno.

https://f80.bimmerpost.com/forums/sh...1521278&page=2

[slaughter.mode]

Old thread but I definitely felt slower throttle response with the BMC drop ins I just re-installed (removed an AFE momentum) but top end it was the same. I think the material of the BMC filters are a bit more restrictive vs. the stock paper ones.

I think we all know the stock S55 intake design is incredible from the factory...I don't really see it ever needing any upgrades until you're in the 28+ PSI range.

[hellokitty]

Are the gains primarily from the removal of charcoal filters rather than the actual filter itself? Anyone seen any data comparing the two?

I’d rather run OEM filters with the charcoal liners removed if the gains are from the removal of the charcoal filters themselves

[1000hp]

Originally Posted by hellokitty

Are the gains primarily from the removal of charcoal filters rather than the actual filter itself? Anyone seen any data comparing the two?

I’d rather run OEM filters with the charcoal liners removed if the gains are from the removal of the charcoal filters themselves

I don't think you'll gain anything significant either way, unless you just want more turbo sounds. Not at all worth it if the car feels slower, IMO.

I removed my charcoal filters and felt no change whatsoever. I can hear a little more turbo but nothing big there either.