Close

Results 1 to 16 of 16
  1. #1
    Join Date
    Apr 2012
    Posts
    79
    Rep Points
    194.0
    Mentioned
    9 Post(s)
    Rep Power
    2


    2 out of 2 members liked this post. Reputation: Yes | No

    Nitrous VS Supercharged Dyno comparison...

    Hey guys. I ended up selling my Ess kit a while back, and I would be lying if I said I didn't miss the extra 200whp. I just installed a 150 shot of nitrous to help me with my obsession with speed. The dyno graph shows the drastic difference in power bands between the two setups. The supercharger graph demonstrates the wonderful linear power progression that a centrifugal blower provides. The nitrous graph is an example of a big kick in the ass when it's time to go fast. I don't consider the nitrous setup to be an equal rival to a supercharged car, so don't misunderstand me. Just wanted to share the results with the community.

    Click here to enlarge

    Click here to enlarge

  2. #2
    Join Date
    Jan 2010
    Location
    SoCal
    Posts
    117,824
    Rep Points
    31,567.1
    Mentioned
    2065 Post(s)
    Rep Power
    316


    Reputation: Yes | No
    That's a huge instant torque gain but it drops off hard toward redline...

    Good post!

  3. #3
    Join Date
    Jan 2012
    Posts
    979
    Rep Points
    2,200.8
    Mentioned
    69 Post(s)
    Rep Power
    23


    Reputation: Yes | No

  4. #4
    Join Date
    May 2010
    Location
    PEI, Canada
    Posts
    1,123
    Rep Points
    1,665.0
    Mentioned
    30 Post(s)
    Rep Power
    17


    Reputation: Yes | No
    Interesting comparison....but that nitrous installation scares the heck out of me!
    Rep Points > Posts since 2010

  5. #5
    Join Date
    Jan 2010
    Location
    SoCal
    Posts
    117,824
    Rep Points
    31,567.1
    Mentioned
    2065 Post(s)
    Rep Power
    316


    Reputation: Yes | No
    Click here to enlarge Originally Posted by PEI330Ci Click here to enlarge
    but that nitrous installation scares the heck out of me!
    Please share why?

  6. #6
    Join Date
    May 2010
    Location
    PEI, Canada
    Posts
    1,123
    Rep Points
    1,665.0
    Mentioned
    30 Post(s)
    Rep Power
    17


    1 out of 1 members liked this post. Reputation: Yes | No
    Click here to enlarge Originally Posted by Sticky Click here to enlarge
    Please share why?
    There is a massive difference in nitrous feed line length between the nozzles; this will give different activation and de-activation for each cylinder bank. My preference would be to have a pair of solenoids for each nozzle, and keeping the line lengths short and exactly the same on each side.

    That massive torque spike you see on the dyno graph....I've done that before....and it corresponded with a massive lean spike. You'd think that it was related to the fuel side not keeping up to the nitrous velocity...and this is partially right...but what's actually going on needs to be seen with a fuel pressure sensor. Opening the fuel solenoid into empty fuel lines before the injection nozzles causes the fuel rail pressure to drop. I've tried to compensate for this by adding fuel to the fuel injectors...but in the end the most solid solution was to add a stand alone fuel system for the nitrous side.

    Oh...and regarding the power drop off: That's what happens with nitrous....you have a constant flow rate that gets divided by RPM. The higher the RPM, the less nitrous per combustion event. You can counter this by ramping the nitrous flow with progressive control....but you need a fairly complex control strategy to do it right...and a lot of flow potential. For 150hp for example...you really need about 320hp of flow to keep the torque flat.
    Rep Points > Posts since 2010

  7. #7
    Join Date
    Jan 2010
    Location
    SoCal
    Posts
    117,824
    Rep Points
    31,567.1
    Mentioned
    2065 Post(s)
    Rep Power
    316


    Reputation: Yes | No
    Click here to enlarge Originally Posted by PEI330Ci Click here to enlarge
    There is a massive difference in nitrous feed line length between the nozzles; this will give different activation and de-activation for each cylinder bank. My preference would be to have a pair of solenoids for each nozzle, and keeping the line lengths short and exactly the same on each side.

    That massive torque spike you see on the dyno graph....I've done that before....and it corresponded with a massive lean spike. You'd think that it was related to the fuel side not keeping up to the nitrous velocity...and this is partially right...but what's actually going on needs to be seen with a fuel pressure sensor. Opening the fuel solenoid into empty fuel lines before the injection nozzles causes the fuel rail pressure to drop. I've tried to compensate for this by adding fuel to the fuel injectors...but in the end the most solid solution was to add a stand alone fuel system for the nitrous side.

    Oh...and regarding the power drop off: That's what happens with nitrous....you have a constant flow rate that gets divided by RPM. The higher the RPM, the less nitrous per combustion event. You can counter this by ramping the nitrous flow with progressive control....but you need a fairly complex control strategy to do it right...and a lot of flow potential. For 150hp for example...you really need about 320hp of flow to keep the torque flat.
    This is explained very well, thanks.

    Going to look into progressive controllers for fun now.

  8. #8
    Join Date
    May 2010
    Location
    PEI, Canada
    Posts
    1,123
    Rep Points
    1,665.0
    Mentioned
    30 Post(s)
    Rep Power
    17


    Reputation: Yes | No
    Click here to enlarge Originally Posted by Sticky Click here to enlarge
    This is explained very well, thanks.

    Going to look into progressive controllers for fun now.
    While it's a better solution than simply on-off....I'm not a big fan of progressive controllers. (I have a $300 one at my shop, and a $1000 one. The more expensive one is really nice...but lacks full integration with engine management) Stand alone ECUs are the way to go...and there a few newer options that do nitrous very very well. Syvecs is my current favourite....

    Edit: Sorry to the OP to take your thread so far off track. I love nitrous....
    Rep Points > Posts since 2010

  9. #9
    Join Date
    Apr 2012
    Posts
    79
    Rep Points
    194.0
    Mentioned
    9 Post(s)
    Rep Power
    2



    Reputation: Yes | No
    Click here to enlarge Originally Posted by PEI330Ci Click here to enlarge
    There is a massive difference in nitrous feed line length between the nozzles; this will give different activation and de-activation for each cylinder bank. My preference would be to have a pair of solenoids for each nozzle, and keeping the line lengths short and exactly the same on each side.
    I agree with equal length lines being ideal. This orientation was acceptable to me only because after thinking about for a while, I believed that the difference in line length is matched by the fuel line lengths. The difference in either intake tube's initial nitrous/fuel mixture is quickly equalized once the intake charge enters the plenum. And of course with that design there is no strict division of air flow between banks. I felt I could get away with it on this size shot, since the afr curve was within a safe range throughout the peak torque curve. Would surely have a direct port setup on anything larger. The fuel curve on this particular dyno graph tapered to becoming overly rich above 5000 rpm. This past weekend I ran the car again with different fuel jets and was able to achieve a nice air/fuel curve. The car made 475/601 and was able to hold power into the upper rpm's much better. I will post the graph tomorrow.
    I must say that it requires a lot of self-control to keep it at a certain size shot and not give in to the temptation to up the shot just a little more. Always want more...

  10. #10
    Join Date
    Jun 2012
    Location
    NJ
    Posts
    4,199
    Rep Points
    1,800.3
    Mentioned
    102 Post(s)
    Rep Power
    19


    Reputation: Yes | No
    Click here to enlarge Originally Posted by PEI330Ci Click here to enlarge
    Syvecs is my current favourite....
    Why Syvecs?? Just wondering cause it seems fairly new (compared to more established options like the MoTeC, ProEFI, Haltech, AEM, etc etc), but has gained a reasonable amount of respect with some tuners working specifically with the GTR & 996/997 Turbos.
    COBB AP ProTune by Bren of ///Bren Tuning
    Akrapovic DP | Helix FMIC | Alpina TCM Flash | Walbro 450LPH Fuel Pump


    "The moment money becomes your motivation, you are immediately not as good as someone who is motivated by passion and internal will." -A. Senna

  11. #11
    Join Date
    May 2010
    Location
    PEI, Canada
    Posts
    1,123
    Rep Points
    1,665.0
    Mentioned
    30 Post(s)
    Rep Power
    17


    Reputation: Yes | No
    Click here to enlarge Originally Posted by Omni Click here to enlarge
    I agree with equal length lines being ideal. This orientation was acceptable to me only because after thinking about for a while, I believed that the difference in line length is matched by the fuel line lengths. The difference in either intake tube's initial nitrous/fuel mixture is quickly equalized once the intake charge enters the plenum. And of course with that design there is no strict division of air flow between banks. I felt I could get away with it on this size shot, since the afr curve was within a safe range throughout the peak torque curve. Would surely have a direct port setup on anything larger. The fuel curve on this particular dyno graph tapered to becoming overly rich above 5000 rpm. This past weekend I ran the car again with different fuel jets and was able to achieve a nice air/fuel curve. The car made 475/601 and was able to hold power into the upper rpm's much better. I will post the graph tomorrow.
    I must say that it requires a lot of self-control to keep it at a certain size shot and not give in to the temptation to up the shot just a little more. Always want more...
    The other temptation is to lower the activation point to increase torque/response.

    Click here to enlarge Originally Posted by benzy89 Click here to enlarge
    Why Syvecs?? Just wondering cause it seems fairly new (compared to more established options like the MoTeC, ProEFI, Haltech, AEM, etc etc), but has gained a reasonable amount of respect with some tuners working specifically with the GTR & 996/997 Turbos.
    You need to go back a decade in motorsports to see where Syvecs has come from. Pi > Pectel > Life Racing > Syvecs

    When you look at the top end of motorsports, you see Pi/Pectel and Life Racing. (Along with Bosch Motorsports, and Magneti Marelli) Before the F1 Engine freeze, and Mclaren SECU in 2006, these are the companies you would find on an F1 car. (And also in LMP/Le Mans cars)

    So while Motec is a high-end ECU, and can be found in most motorsports, it does not have a history of being at the top level of motorsports. The reason is pretty simple: Top level racing requires bespoke hardware and software, which is not Motec's aim. Pi/Pectel, and Life Racing specialize in this.

    Life Racing = Syvecs

    Syvecs is the "tuner" product support.

    Why is Syvecs my choice for nitrous control? Pretty simple: They have developed the best Nitrous control strategy I have found across all commercially available ECU products. (This includes stand-alone nitrous controllers)

    But....in the coming year we will see software support for user-definable control strategies from AEM for the Infinity product line, and from Motec for the M1 product line. These will offer the ability for even better control strategies, but will require a fairly high level of understanding of ECU logic functions.
    Rep Points > Posts since 2010

  12. #12
    Join Date
    Apr 2012
    Posts
    79
    Rep Points
    194.0
    Mentioned
    9 Post(s)
    Rep Power
    2



    Reputation: Yes | No
    Here is a more recent graph with the fuel mixture tuned...


    Click here to enlarge

  13. #13
    Join Date
    Jan 2010
    Location
    SoCal
    Posts
    117,824
    Rep Points
    31,567.1
    Mentioned
    2065 Post(s)
    Rep Power
    316


    Reputation: Yes | No
    Do you have a larger graph? It's pretty small.

  14. #14
    Join Date
    May 2010
    Location
    PEI, Canada
    Posts
    1,123
    Rep Points
    1,665.0
    Mentioned
    30 Post(s)
    Rep Power
    17


    Reputation: Yes | No
    Click here to enlarge Originally Posted by Omni Click here to enlarge
    Here is a more recent graph with the fuel mixture tuned...


    http://www.germanboost.com/images/im...14d52cf6-1.jpg
    Do you have the DRF file for that?
    Rep Points > Posts since 2010

  15. #15
    Join Date
    Apr 2012
    Posts
    79
    Rep Points
    194.0
    Mentioned
    9 Post(s)
    Rep Power
    2



    Reputation: Yes | No
    Click here to enlarge Originally Posted by PEI330Ci Click here to enlarge
    Do you have the DRF file for that?
    yea i can get it tomorrow.

    The afr curve early in this run was smooth and did not fluctuate in sync with the wavering power curve up till ~5000 rpm. No detonation, but i can see the ignition advance was dancing back and forth, reacting to the nitrous.
    Attached Images Attached Images  

  16. #16
    Join Date
    May 2010
    Location
    PEI, Canada
    Posts
    1,123
    Rep Points
    1,665.0
    Mentioned
    30 Post(s)
    Rep Power
    17


    Reputation: Yes | No
    Click here to enlarge Originally Posted by Omni Click here to enlarge
    yea i can get it tomorrow.

    The afr curve early in this run was smooth and did not fluctuate in sync with the wavering power curve up till ~5000 rpm. No detonation, but i can see the ignition advance was dancing back and forth, reacting to the nitrous.
    Do you have the .drf file?
    Rep Points > Posts since 2010

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
  •