Close

Page 1 of 2 12 LastLast
Results 1 to 25 of 35
  1. #1
    Join Date
    Nov 2009
    Location
    Simi Valley, CA
    Posts
    8,220
    Rep Points
    9,376.5
    Mentioned
    656 Post(s)
    Rep Power
    94


    1 out of 1 members liked this post. Yes Reputation No

    "Hot air intake" myth testing -- Revisited

    Hey guys,

    It's been around three years (!) since we did our first intake air temperature testing which showed open element intakes do not result in higher air intake temperatures or "heat soak" as many assumed it would. But back then when we did the original testing the car had a larger intercooler which many felt skewed the results and the testing was done with an OBDII tool which was a little difficult to read. We also omitted the critical "stuck in traffic" test.

    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 safe private road) to evaluate the intake temperature increases throughout the run. Secondly an 8 minute (limit of JB4 logs) driveway 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 in the driveway soaking up all that engine heat. :popcorn

    First up: Stock intake system

    Click here to enlarge

    Click here to enlarge

    Click here to enlarge


    Next up: BMS Dual Cone Intake

    Click here to enlarge

    Click here to enlarge

    Click here to enlarge

    Results:

    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. I should also add it's certainly possible modifying your OEM airbox with an extra filter might offer minimal gains over a dual cone intake assuming you don't mind up cutting up your factory airbox but don't expect much. We've tested this as well with no significant performance gain over a DCI in 40-120mph VBOX times. 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...

  2. #2
    Join Date
    Dec 2010
    Posts
    804
    Rep Points
    607.0
    Mentioned
    2 Post(s)
    Rep Power
    7


    Yes Reputation No
    Very interesting results. It's worth mentioning that Procharger also uses an open element filter under the hood of their 5th gen Camaro centri kits. I always thought it was strange, but they obviously find it to work well and your tests show this kind of application works well on the 135I.

    That said, Kenne Bell basically hangs their hat on the theory that underhood filters rob power because of higher intake temps. Seems like a good topic for debate. But, clearly, you can't argue with your logs.

  3. #3
    Join Date
    Sep 2010
    Location
    Mildenhall, UK
    Posts
    749
    Rep Points
    681.0
    Mentioned
    4 Post(s)
    Rep Power
    7


    Yes Reputation No
    Nice stuff Terry, thanks for reconfirming the results. Now if only people on other boards will believe the results and let this argument die.
    2010 335i Coupe Le Mans Blue
    *JB4 Powered*

  4. #4
    Join Date
    Nov 2010
    Location
    Netherlands
    Posts
    6,303
    Rep Points
    6,878.8
    Mentioned
    81 Post(s)
    Rep Power
    69


    Yes Reputation No
    One drawback of an DCI is the noise.
    It is loud as $#@! on WOT.
    That is why I will not even considder it on my 135i.
    There are two theories to arguing with women. Neither one works

  5. #5
    Join Date
    Mar 2010
    Location
    www.bootmod3.com
    Posts
    6,693
    Rep Points
    3,352.2
    Mentioned
    227 Post(s)
    Rep Power
    34


    Yes Reputation No
    Noise is actually the reason I'm going with the mr. 5 design, should be a bit quieter and from testing others have done it performs at least as good as a DCI setup if not a touch better
    Click here to enlarge

  6. #6
    Join Date
    Nov 2009
    Location
    Miami, FL.
    Posts
    1,836
    Rep Points
    771.0
    Mentioned
    9 Post(s)
    Rep Power
    8


    Yes Reputation No
    im happy with my closed intake but thanks for the testing terry, this is helpful to people on the fence
    Click here to enlarge
    2007 335i Coupe
    Mods: Check the Garage

  7. #7
    Join Date
    Jul 2011
    Posts
    2
    Rep Points
    18.0
    Mentioned
    0 Post(s)
    Rep Power
    0


    Yes Reputation No
    Why did timing drop with the DCI?

  8. #8
    Join Date
    Nov 2010
    Posts
    937
    Rep Points
    562.7
    Mentioned
    52 Post(s)
    Rep Power
    6


    Yes Reputation No
    How about WGDC, what's your estimate on reduction with DCI at higher boost in the top(maybe 15psi at 6000rpm)?

  9. #9
    Join Date
    Nov 2009
    Location
    Simi Valley, CA
    Posts
    8,220
    Rep Points
    9,376.5
    Mentioned
    656 Post(s)
    Rep Power
    94



    Yes Reputation No
    Click here to enlarge Originally Posted by JoshBoody Click here to enlarge
    How about WGDC, what's your estimate on reduction with DCI at higher boost in the top(maybe 15psi at 6000rpm)?
    Duty cycle was 2-3% lower (which is where the performance gains come from) but I don't have a clean log to show you of it from the above testing, I hijacked those fields for something else we're working on.

  10. #10
    Join Date
    Nov 2009
    Location
    Simi Valley, CA
    Posts
    8,220
    Rep Points
    9,376.5
    Mentioned
    656 Post(s)
    Rep Power
    94



    Yes Reputation No
    Click here to enlarge Originally Posted by 2nr1 Click here to enlarge
    Why did timing drop with the DCI?
    I'm running the car overly aggressively for some testing so cylinder1 timing isn't as stable as it would be on say map 1. The drop in 4th gear with the DCI is no more related to the intake than the lower timing at the bottom of 3rd with the stock airbox was.

  11. #11
    Join Date
    Sep 2011
    Location
    Raleigh, NC
    Posts
    148
    Rep Points
    196.6
    Mentioned
    1 Post(s)
    Rep Power
    2


    Yes Reputation No
    Hey Terry! Thanks for posting This up. Do you happen to have any testing data, like this, when it's a bit hotter outside? I see your runs were done when it's 52 degrees (is that correct?). That is great in the winter (in NC), but in the summer here we are 90-95 degrees. I'd be really interested in seeing both the idle test and the runs when the ambient air is much higher.

    Thanks for taking the time to post these!
    2008 BMW 535iA | Cobb Stg2+ | FBO | Meth

  12. #12
    Join Date
    Nov 2009
    Location
    Simi Valley, CA
    Posts
    8,220
    Rep Points
    9,376.5
    Mentioned
    656 Post(s)
    Rep Power
    94



    Yes Reputation No
    Click here to enlarge Originally Posted by xclone Click here to enlarge
    Hey Terry! Thanks for posting This up. Do you happen to have any testing data, like this, when it's a bit hotter outside? I see your runs were done when it's 52 degrees (is that correct?). That is great in the winter (in NC), but in the summer here we are 90-95 degrees. I'd be really interested in seeing both the idle test and the runs when the ambient air is much higher.

    Thanks for taking the time to post these!
    It was around 72 degrees out for this testing. Next time we have an upper 90s degree day I'll retest but have done that test before and the results were similar.

  13. #13
    Join Date
    Sep 2011
    Location
    Raleigh, NC
    Posts
    148
    Rep Points
    196.6
    Mentioned
    1 Post(s)
    Rep Power
    2


    Yes Reputation No
    Thanks Terry. I've got the DCI's already and swapped my stock airbox back on to compare the differences. My main concern is if the "heat soak" differences are linear when the ambient temps are higher or is there a compounding affect when the outside temperature is already high (95 degrees or higher).

    FWIW I liked the DCI's but don't have the knowledge/time at this point to do alot of in depth testing on the performance of both the stock airbox and DCI's in hot weather.

    Again, thanks - much appreciated!
    2008 BMW 535iA | Cobb Stg2+ | FBO | Meth

  14. #14
    Join Date
    Nov 2009
    Location
    Simi Valley, CA
    Posts
    8,220
    Rep Points
    9,376.5
    Mentioned
    656 Post(s)
    Rep Power
    94



    Yes Reputation No
    The idle test is really easy to recreate. Just start a JB4 log and let the car idle 8+ minutes, and see how high IAT goes. Then recreate with DCI. You can even monitor IAT in dash if you're too lazy to get the laptop out. Click here to enlarge

  15. #15
    Join Date
    Sep 2011
    Location
    Raleigh, NC
    Posts
    148
    Rep Points
    196.6
    Mentioned
    1 Post(s)
    Rep Power
    2


    Yes Reputation No
    Click here to enlarge Originally Posted by Terry@BMS Click here to enlarge
    The idle test is really easy to recreate. Just start a JB4 log and let the car idle 8+ minutes, and see how high IAT goes. Then recreate with DCI. You can even monitor IAT in dash if you're too lazy to get the laptop out. Click here to enlarge
    I'll do that with my cobb. Of course, now we are having seasonal temps so I will try and do that when we get into a really hot day. Thanks Terry!
    2008 BMW 535iA | Cobb Stg2+ | FBO | Meth

  16. #16
    Join Date
    Jul 2011
    Posts
    5
    Mentioned
    0 Post(s)
    Rep Power
    0


    0 out of 1 members liked this post. Yes Reputation No
    woooow

  17. #17
    Join Date
    Feb 2010
    Location
    NJ
    Posts
    13,426
    Rep Points
    58.0
    Mentioned
    318 Post(s)
    Rep Power
    0


    Yes Reputation No
    I appreciate the time put into this, but it must be frustrating to have to go in circle everytime a new newb comes on scene. I'd much rather see new features, like the dtc off option coming around.

  18. #18
    Join Date
    Nov 2010
    Location
    USA
    Posts
    1,923
    Rep Points
    1,825.9
    Mentioned
    11 Post(s)
    Rep Power
    19


    Yes Reputation No
    Thanks for the tests Terry. I will stay with my DCI's Click here to enlarge

  19. #19
    Join Date
    Nov 2009
    Location
    Simi Valley, CA
    Posts
    8,220
    Rep Points
    9,376.5
    Mentioned
    656 Post(s)
    Rep Power
    94



    Yes Reputation No
    Click here to enlarge Originally Posted by LostMarine Click here to enlarge
    I appreciate the time put into this, but it must be frustrating to have to go in circle everytime a new newb comes on scene. I'd much rather see new features, like the dtc off option coming around.
    I hear you... Fortunately testing like this is pretty simple. The nay-sayers had a valid point about the testing three years ago involving an intercooler so it made sense to devote another hour or two to a follow up thread. That DTC off option and menu 9 boost additive adjustment are both ready for beta testing. Just drop me a note if you want to try them out. Click here to enlarge

  20. #20
    Join Date
    Feb 2010
    Location
    NJ
    Posts
    13,426
    Rep Points
    58.0
    Mentioned
    318 Post(s)
    Rep Power
    0


    Yes Reputation No
    I'm away until Saturday and my car is out of the bodyshop on friday, I still gotta install the FSB, and update from 7/20 firmware, so I have a lot of catching up to do.. and i think there is an MIR rental coming up quick. So u know I'm down to get some logs and try a few things to run the elusive sub10 sec 1/4 Click here to enlarge

  21. #21
    Join Date
    Nov 2009
    Location
    Miami, FL.
    Posts
    1,836
    Rep Points
    771.0
    Mentioned
    9 Post(s)
    Rep Power
    8


    Yes Reputation No
    Click here to enlarge Originally Posted by LostMarine Click here to enlarge
    run the elusive sub10 sec 1/4
    you mean sub11, sub 10 would mean 9's Click here to enlarge but good luck LM, you're the closest n54 so far!
    Click here to enlarge
    2007 335i Coupe
    Mods: Check the Garage

  22. #22
    Join Date
    Nov 2009
    Location
    Simi Valley, CA
    Posts
    8,220
    Rep Points
    9,376.5
    Mentioned
    656 Post(s)
    Rep Power
    94



    Yes Reputation No
    Click here to enlarge Originally Posted by LostMarine Click here to enlarge
    I'm away until Saturday and my car is out of the bodyshop on friday, I still gotta install the FSB, and update from 7/20 firmware, so I have a lot of catching up to do.. and i think there is an MIR rental coming up quick. So u know I'm down to get some logs and try a few things to run the elusive sub10 sec 1/4 Click here to enlarge
    Sounds good. I hope the trans can hold up!

  23. #23
    Join Date
    May 2010
    Location
    canada
    Posts
    522
    Rep Points
    122.9
    Mentioned
    2 Post(s)
    Rep Power
    2


    Yes Reputation No
    that's a significant IAT rise during the road test, no? intercooler not up to par?

  24. #24
    Join Date
    Nov 2009
    Location
    Simi Valley, CA
    Posts
    8,220
    Rep Points
    9,376.5
    Mentioned
    656 Post(s)
    Rep Power
    94



    Yes Reputation No
    The factory intercooler does OK. Certainly a few HP to be gained going to a larger one (like the CPE or Helix we carry) with less of a pressure drop and better cooling. But it is what it is and many run 11s on the stock intercooler.

  25. #25
    Join Date
    Feb 2010
    Posts
    325
    Rep Points
    467.6
    Mentioned
    8 Post(s)
    Rep Power
    5


    Yes Reputation No
    I remain unconvinced. When I tested the dci vs the stock box and stock filter the dci did worse. The mr. 5 intake is the only intake that I've seen an improvement from.

    Dci vs stock:
    http://www.bimmerboost.com/showthread.php?15476-My-Mr.-5-intake-with-logs

    Stock vs mr. 5:
    http://www.bimmerboost.com/showthread.php?15476-My-Mr.-5-intake-with-logs


    And, oh god please let lostmarine come to MIR on the 7th. I'll pay for your race gas.

Page 1 of 2 12 LastLast

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •