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    • The 2021 G80 BMW M3 will be well over 600 horsepower stock - Heavily underrated F98 X4M Competition S58 dyno shows 520 all wheel horsepower

      If you are not aware BMW is heavily sandbagging output with turbo M motors then you simply have not been paying attention for the past decade. Here is yet another example in the new 2020 BMW F98 X4M Competition and its S58 motor which is rated at 503 horsepower.


      Well, here it is making 520 horsepower to all four wheels in Arizona 119 degree heat on 91 octane pump gas:


      BMW's horsepower ratings are just a joke at this point. They say 503 at the crank and it has more than that at all four wheels. This is easily a 600+ horsepower car.

      Even if you go with conservative 15% drivetrain losses which are traditionally reserved on a Dynojet for a RWD manual vehicle that would mean output is 611 crank horsepower. If you go with 20% losses, we are talking 650 horsepower.

      The G80 M3 gets this same S58 motor and basic drivetrain in a lighter package. 600+ horsepower only makes sense. Why? BMW since the E46 M3 increases horsepower by approximately 75 whp each generation. They simply started sandbagging with the F80 M3 massively.

      E46 M3 - 275 whp
      E92 M3 - 350 whp
      F80 M3 - 425 whp
      G80 M3 - ~500 awhp

      The E92 M3 to F80 M3 horsepower rating went from 414 to 425 at the crank. Yet, wheel output increased by 75+ horses. Explain that.

      With the G80 prepare for a dragster that will be well into the 10's tune only.

      This article was originally published in forum thread: The 2021 G80 BMW M3 will be well over 600 horsepower stock - Heavily underrated F98 X4M Competition S58 dyno shows 520 all wheel horsepower started by Sticky View original post
      Comments 66 Comments
      1. Bowser330's Avatar
        Bowser330 -
        Someone better get started on developing transmission upgrades for the g80 and f90
      1. CobraMarty's Avatar
        CobraMarty -
        Is it twin turbo? Must be.
      1. maxnix's Avatar
        maxnix -
        Click here to enlarge Originally Posted by CobraMarty Click here to enlarge
        Is it twin turbo? Must be.
        Yes on both turbos and twinned HPFP.
      1. maxnix's Avatar
        maxnix -
        Click here to enlarge Originally Posted by Bowser330 Click here to enlarge
        Someone better get started on developing transmission upgrades for the g80 and f90
        I rather imagine BMW engineers specified the correct version of the ZF 8HP transmission.

        Maybe the RR and 760 LXi version? Same as M5 version?
      1. Stevenh's Avatar
        Stevenh -
        The Dyno can say whatever it wants to. Physics tells me a 4,500lb car that traps about 115mph is making roughly 550 at the crank.
      1. Sticky2's Avatar
        Sticky2 -
        Click here to enlarge Originally Posted by Stevenh Click here to enlarge
        The Dyno can say whatever it wants to. Physics tells me a 4,500lb car that traps about 115mph is making roughly 550 at the crank.
        An SUV will have more drag. Taller and larger frontal area.
      1. Stevenh's Avatar
        Stevenh -
        600whp at that weight should trap over 125mph. Aero can explain a little bit of that gap, but not 10mph worth.
      1. Sticky2's Avatar
        Sticky2 -
        Click here to enlarge Originally Posted by Stevenh Click here to enlarge
        600whp at that weight should trap over 125mph. Aero can explain a little bit of that gap, but not 10mph worth.
        Well don't forget it was Arizona too. Either way it's making a ton more power than BMW says.
      1. BLKROKT's Avatar
        BLKROKT -
        Are you saying that BMW is sandbagging hp on cars that are already consistently underperforming and underwhelming in independent tests? Unlikely.
      1. Payam@BMS's Avatar
        Payam@BMS -
        Click here to enlarge Originally Posted by BLKROKT Click here to enlarge
        Are you saying that BMW is sandbagging hp on cars that are already consistently underperforming and underwhelming in independent tests? Unlikely.
        Are they really though?
      1. CobraMarty's Avatar
        CobraMarty -
        If the head on this S58 is like the B58 with the integrated exhaust manifold, and with twin turbos and twin HPFPs, It is basically 2 separate 3 cylinder engines paired together in an inline configuration. Sort of like a V6 but configured to be inline.

        Imagine a 1500cc 3 cylinder turbo engine that makes 250 HP. Now times 2.
        91.5 CID x 1.30-1.40hp/cid = 120-128hp x 14-16 pounds boost = 250 HP

        With 30 pounds boost, that is 500 HP x 2.
      1. richpike's Avatar
        richpike -
        Not to say this motor isn’t underrated (because it is), but the old drivetrain loss figures just really don’t apply anymore. There is such a focus on efficiency that I’d bet losses are closer to 5-10% now. Even for AWD. Torque converter lock up almost immediately. AWD isn’t really AWD unless it detects a slip. Tesla got another 20 miles of range by switching wheel bearings. Drivetrains have just become far more efficient. That doesn’t mean this isn’t underrated - it clearly is if the whp is more than the rated crank HP, but I don’t think it’s a 600+HP engine.

        -Rich
      1. Stevenh's Avatar
        Stevenh -
        I'll believe these numbers as soon as I see a 120mph trap. Do we know if the Dyno was correcting for the heat?
      1. Blown6's Avatar
        Blown6 -
        You will need a lot of boost for a prod 3.0 to hit 600+
      1. Stevenh's Avatar
        Stevenh -
        Click here to enlarge Originally Posted by Blown6 Click here to enlarge
        You will need a lot of boost for a prod 3.0 to hit 600+
        Not at all. Especially when you consider this thing is making power to 7500 rpm. 20lbs and it should be making that to the wheels.
      1. Blown6's Avatar
        Blown6 -
        Looks like it makes power to 6500 holds it to 6800 then nosedives. It wont be holding 20psi of boost to 7500 on stock turbos, thats 4sure.... anyways it needs to hold ~26psi to 7000rpm to make 600
      1. Stevenh's Avatar
        Stevenh -
        Click here to enlarge Originally Posted by Blown6 Click here to enlarge
        Looks like it makes power to 6500 holds it to 6800 then nosedives. It wont be holding 20psi of boost to 7500 on stock turbos, thats 4sure.... anyways it needs to hold ~26psi to 7000rpm to make 600
        Yes, that is the stock tunes torque curve in 119 degree heat. I'm not sure how that relates to a motors potential... 26lbs at 7000 rpm in 3l is more like 800chp.
      1. Blown6's Avatar
        Blown6 -
        Click here to enlarge Originally Posted by Stevenh Click here to enlarge
        Yes, that is the stock tunes torque curve in 119 degree heat. I'm not sure how that relates to a motors potential... 26lbs at 7000 rpm in 3l is more like 800chp.
        Its not the graph above but the AMS graph here which shows rpms not mph:

        Attachment 59362

        S58 Redline is 7200, so how is a stock motor making power to 7500.... anyways it nosedives after 6800

        To allow the S58 to spin past 7,000 rpm, it has a shorter stroke. The new engine’s 473 hp (503 hp in the Competition model) is achieved with 32 peak psi of boost (33.4 psi in Competition models) delivered from two mono-scroll turbos that serve three cylinders each and use an electronic wastegate to maximize the response. And helping to keep it all cool is a new water-to-air intercooler system.

        https://autoweek.com/article/car-rev...-velvet-hammer

        3.0:

        Boost____Abs Press_____Theoretical WHP @ 15.23 HP/Abs Pressure (psi)
        8__________22.6_________346
        10_________24.7_________376
        12_________26.7_________407
        14_________28.7_________437
        16_________30.7_________468
        18_________32.7_________498
        20_________34.7_________528
        22_________36.7_________559
        24_________38.7_________589
        26_________40.7_________620
      1. Stevenh's Avatar
        Stevenh -
        It's not about peak torque. It's about maintaining torque. If the turbos could flow the air to make that 446ftlb at 7,000 rpm the car would be making nearly 600whp.

        The table you posted is ridiculous. Boost dictates torque. RPM determines horsepower.
      1. billvp's Avatar
        billvp -
        Click here to enlarge Originally Posted by Stevenh Click here to enlarge
        I'll believe these numbers as soon as I see a 120mph trap. Do we know if the Dyno was correcting for the heat?
        it says it is using a Correction Factor (STD), so yes it was