View Single Post
Terry @ BMS's Avatar
Terry @ BMS Terry @ BMS is offline
Posts: 28,700
Join Date: Jan 2008
Default DCI Hot Air Myth Testing - 03-25-2014, 04:33 PM

Repost from 2012:

So for this round of testing we used our 135i which happens to be 100% stock at the moment aside from the JB4 using 91 octane + NOS octane booster (~93 octane). I've been testing map 2 with a default CPS offset lately so kept that all the same between both tests.

The two sets of tests were performed within 20 minutes of each other under identical conditions. First I did a 40-110mph sprint (on a private track) to evaluate the intake temperature increases throughout the run. Secondly an 8 minute (limit of JB4 logs) idle test simply logging the car with the hood down and AC on to monitor intake temperatures at rest.

According to "hot air" conspiracy theorists the dual cone intake should result in higher intake temperatures during the wide open throttle run, no power gains, and heat up dramatically sitting at idle soaking up all that engine heat.

First up: Stock intake system

Next up: BMS Dual Cone Intake


I hate to say it again but the results were exactly as expected. The DCI did not produce higher air intake temperatures at wide open throttle, did not heat soak more sitting at a standstill for 8 minutes, and all around felt faster.

The primary reason for this is that the filter inlet temps have a very minimal effect on the engine inlet temps. At idle the low air volume circles around the hot turbo/manifold, and across an intercooler with no airflow, resulting in increasing temperatures regardless of the inlet temperature. At full throttle air in the engine bay is full consumed by the engine every few seconds, the heat at full throttle comes from the compression within the turbocharger and then is offset by the intercooler. Again the filter inlet temperatures have very little effect on the engine inlet temperatures. But the turbo able to draw air in more with less restriction efficiently increases boost and in itself offsets any filter inlet temperature difference.

You have a lot of options for intakes but three+ years later the tried and true DCI is still the intake of choice for those of us who are serious about performance...

Burger Motorsports
Home of the Worlds fastest N20s, N54s, N55s, S55s, N63s, and S63s!

It is the sole responsibility of the purchaser and installer of any BMS part to employ the correct installation techniques required to ensure the proper operation of BMS parts, and BMS disclaims any and all liability for any part failure due to improper installation or use. It is the sole responsibility of the customer to verify that the use of their vehicle and items purchased comply with federal, state and local regulations. BMS claims no legal federal, state or local certification concerning pollution controlled motor vehicles or mandated emissions requirements. BMS products labeled for use only in competition racing vehicles may only be used on competition racing vehicles operated exclusively on a closed course in conjunction with a sanctioned racing event, in accordance with all federal and state laws, and may never be operated on public roads/highways. Please click here for more information on legal requirements related to use of BMS parts.
Reply With Quote