Close

    • Rob Beck N54 (335/135) Turbos Dyno'd at 5500ft altitude

      As a lot of you know I live in Johannesburg South Africa which is 5500ft above sea level. Tuning of the car is a work in progress but I got a opportunity today to give the car a run on a dyno just to see where I am at with my "street" map. Runs where done with 93 and meth (CM10) and the temp was 30 degrees celsius with no cooling of the car. We have not touched the tuning much above 6000rpm as we had to make sure we had the fueling waxed at lower high torque rpms. Boost pressure was set at 19psi and tapered to 15psi at the higher rpm. The timing is also very conservative and I am confident to say that we can push 475whp in race trim comfortably. So far Chip Logic does not seem to have hit any barriers in the tuning of larger turbos using flash software.

      A ten percent gain should be added for coastal figures.

      The comparative graph is of the same car without the turbos and exhaust. A stock 335 makes 245-255whp on this same dyno so we looking at a full 200whp gain currently at this altitude. It would be nice to hear from some people who have done tests at high altitude to see how they compare.

      The next step is to pour some race fuel and run the 19psi to redline and see how it reflects.


      This article was originally published in forum thread: RB Turbos Dyno at 5500ft altitude started by George Smooth View original post
      Comments 26 Comments
      1. Sticky's Avatar
        Sticky -
        Promoted to front page.

        Great stuff George!

        If we could get a larger graph that would be great.
      1. fundahl's Avatar
        fundahl -
        The low and mid-range torque that the 3.0L N54 makes with the right parts puts a lot of V8's to shame!

        Based on what you have said it seems you were getting knock activity without the 19-15psi taper on 93 and CM10 (what pressure?). Is this true or are you just not wanting to test less taper yet on pump/meth combo?

        Thanks for the update and dyno chart, and I look forward to your race gas testing!
      1. enrita's Avatar
        enrita -
        Click here to enlargeClick here to enlargeClick here to enlarge
        nice will soon do one as well to compaire.

        Any chance you could disclose the AFR throughtout the rpm range?
      1. George Smooth's Avatar
        George Smooth -
        Click here to enlarge Originally Posted by 654 Click here to enlarge
        Good stuff. It seems that despite of the bigger turbos, you don't have the typical big turbo dyno graph staying lower than stock until higher revs. Actually I'm positively surprised that at 2500 RPM the RB turbos seem to be way stronger than stockers! Looks like that they might be stronger all the way from idle.
        I was also highly surprised with spool up.

        Click here to enlarge Originally Posted by SlicktopTTZ Click here to enlarge
        The low and mid-range torque that the 3.0L N54 makes with the right parts puts a lot of V8's to shame!

        Based on what you have said it seems you were getting knock activity without the 19-15psi taper on 93 and CM10 (what pressure?). Is this true or are you just not wanting to test less taper yet on pump/meth combo?

        Thanks for the update and dyno chart, and I look forward to your race gas testing!
        We have two maps we working on, one is for the street and another which is track specific and race gas. This was on the street map with very conservative timing. We left the boost tapered as we where still working on midrange tuning and fueling at the top without taking to much risk before increasing the boost. The main testing was done by loading the car at various increments and making sure the fueling is more than adequate. Ultimately the line can stay straight and now that the fueling is figured and the knock threshold we will clean the top up with much more boost and timing.

        Click here to enlarge Originally Posted by enrita Click here to enlarge
        Click here to enlargeClick here to enlargeClick here to enlarge
        nice will soon do one as well to compaire.

        Any chance you could disclose the AFR throughtout the rpm range?
        In this run the AFR in various increments are: 3000rpm 13.4 3600rpm 12.8 4400rpm 12.5 4800rpm 12.2 5200rpm 11.9 5500rpm 11.7
      1. RLSinCO's Avatar
        RLSinCO -
        Interesting reading, as I also live 5,000 feet above sea level, and drive quite often at altitudes 10,000 feet above sea level.
      1. fundahl's Avatar
        fundahl -
        So this is more of a test/tuning run, as you are playing with A/F ratios and did not rev it out all the way?

        Did you hold that 11.7:1 to redline? That is pretty rich, but I'd rather be safe than sorry! Click here to enlarge
      1. 654's Avatar
        654 -
        Are you able to measure or adjust the AFRs for each cylinder separately?
      1. George Smooth's Avatar
        George Smooth -
        Click here to enlarge Originally Posted by SlicktopTTZ Click here to enlarge
        So this is more of a test/tuning run, as you are playing with A/F ratios and did not rev it out all the way?

        Did you hold that 11.7:1 to redline? That is pretty rich, but I'd rather be safe than sorry! Click here to enlarge
        The run was just a screw around run. The AF at the point it gets rich is due to the methanol as we are not finished the flash meth failsafe and are still experimenting with solutions. With the meth off its around 12.2 right through.

        Click here to enlarge Originally Posted by 654 Click here to enlarge
        Are you able to measure or adjust the AFRs for each cylinder separately?
        Cannot measure the AFR's and I cannot imagine needing to do each cylinder seperate as the DI Injectors differences are pre programmed when they get installed.
      1. enrita's Avatar
        enrita -
        thanks for sharing the info ! think is important to share AFR so that everybody has a start point or at least knows they are safe running those on certain levels of boost, octane etc.
      1. fundahl's Avatar
        fundahl -
        Yeah the ECU will throw a code and tell you if one cylinder A/F ratio is off by too much anyway.

        This is a very smart car.
      1. enrita's Avatar
        enrita -
        by the way George if you have access to a Vbox/Pbox would be great if you could do some runs from 60 mph up to compare with mine (19 psi and meth)
        Attachment 4586
      1. Sticky's Avatar
        Sticky -
        Sorry, I don't remember Enrita, did you run a 60-130?
      1. 654's Avatar
        654 -
        Click here to enlarge Originally Posted by George Smooth Click here to enlarge
        Cannot measure the AFR's and I cannot imagine needing to do each cylinder seperate as the DI Injectors differences are pre programmed when they get installed.
        What do you mean by this?

        I've been following Procede logs that show AFRs for both banks, might be for one cylinder in each bank, and several logs that I've seen show very different AFR values for the banks.

        I've figured there is a problem in either Procede or in N54 cylinder AFR variances in general.
      1. enrita's Avatar
        enrita -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Sorry, I don't remember Enrita, did you run a 60-130?
        nope otherwise i would have posted them.

        Concerning AFR for both banks those should be equal and not differentiate.
      1. LostMarine's Avatar
        LostMarine -
        RB FTW!! Nice job george. i realize this is all just part of the tuning, thats what my dyno session was as well. Id have to say, that you have no reason not to crack the 5xx hp mark, and smash my personal best. with better controlling these suckers have really proven to be even better than i initially realized. the power under the curve is just amazing. Good job and keep it up.. it will motivate me to get back on the dyno as well
      1. George Smooth's Avatar
        George Smooth -
        Click here to enlarge Originally Posted by 654 Click here to enlarge
        What do you mean by this?

        I've been following Procede logs that show AFRs for both banks, might be for one cylinder in each bank, and several logs that I've seen show very different AFR values for the banks.

        I've figured there is a problem in either Procede or in N54 cylinder AFR variances in general.
        What you talking about is measuring each three banks in the downpipe. This is completely different than each cylinder.
        The variances exist because the not all after market downpipes are made equally. The lambda sensors have been put in different places with fitment being a priority before functionality. If you measure the AFR on the stock downpipes there is no variance and if there is then you might have a faulty sensor. Procede does right in using the leaner of the two. I have seen some downpipes where the sensor placement was half out on the one and the other was to far in, hence a variance.
      1. Yukohama's Avatar
        Yukohama -
        very nice, cant wait to see final tuning results
      1. enrita's Avatar
        enrita -
        George you should update your sig :-)
      1. George Smooth's Avatar
        George Smooth -
        Sig updated. I am going to post up a run where we used fourth gear and it overshot the boost target by 1psi. Torque jumped up to 714nm - thats a whopping 526lb ft of torque.
      1. fundahl's Avatar
        fundahl -
        Click here to enlarge Originally Posted by George Smooth Click here to enlarge
        Sig updated. I am going to post up a run where we used fourth gear and it overshot the boost target by 1psi. Torque jumped up to 714nm - thats a whopping 526lb ft of torque.
        DAMN! That's a lot of ft-lbs to play with, hope it held on to some of it up top!

        Can't wait to see the chart! Click here to enlarge