So how does DCIs compare to stock and modified air boxes…the results are in

[pbondar]

For those not following the other thread on airbox discussions here’s the abridged version..

All on an E89 35is running TTE500 turbos on 99 RON fuel..

So here’s the answer to ‘well how does it compare to DCIs?’…

Today’s dyno runs..

The chart with 3 lines is tune V17 (iteration 19) which has been tweaked to reduce timing corrections and improve spool..peak power is slightly down on the earlier v13+..torque up..two versions one with the Mr.5 mod and one using DCIs…compared to v13+ with the Mr.5 mod…

The chart with 5 lines is version 6 of the tune ..revisited twice..once with a Mr.5 mod and one with DCIs

 

[CantSitStill]

Great to see some actual tests on the dyno mate. So looks like the DCI's are flowing more in the mid range (25HP more!!), do you have a log for these runs by any chance? Do you taper boost up top considerably as Mr 5 and DCI seem to be equal at higher RPM's which is surprising if the DCI is providing more air/power mid range

 

[pbondar]

Great to see some actual tests on the dyno mate. So looks like the DCI's are flowing more in the mid range (25HP more!!), do you have a log for these runs by any chance? Do you taper boost up top considerably as Mr 5 and DCI seem to be equal at higher RPM's which is surprising if the DCI is providing more air/power mid range

I do have the logs as I left the MHD data logger running for the whole dyno session..I’ll try and find the relevant ones and post them..given that this behaviour on the DCIs is relatively consistent across several tunes and configs I surmise that the primary reason for their strong mid range torque increase is the removal of destructive interference effects caused by pulses from the inlets merging and interacting in the airbox..there is not enough physical volume to allow these pulses to dissipate without interfering with each other..in the engine bay the DCIs can dissipate these pulses in part through their construction and in part due to venting into a much larger volume..

You see a modest similar effect when you remove the air filter or change it to a foam filter..peak torque increases a bit but high end power not much…