I fully understand what you are saying. You have the empirical data of having run your sled on an engine dyno (265 HP) and backed that data up with a track dyno showing 144HP, that is a driveline efficiency factor of .545 which means you lost ~45% of the power through the driveline components. If you look at a car scenario, you typically see 15-20% loss from engine HP to wheel HP, and another 4-7% on top of that if you use an automatic instead of a manual gearbox. That number, whatever it is, is not transferable from sled model to sled model because the drivetrains change quite a bit. .57 is a rule of thumb but in your case you can see that the actual loss was higher resulting in .545 or 45% loss in power through the drivetrain. When you improved your track HP to 150, the engine HP would have to go up proportionally to ~275HP unless you changed something fundamental about the driveline. My guess is that to get to 150, you were tuning more HP into engine, not playing with the driveline or a bit of both, but mostly engine because driveline changes are harder and result in lower gains. Your position on TD is that their track dyno number and conversion rate of .5 is artificially inflating their engine number. If they are, lets look at that. Their stated baseline was a 211HP stock winder. If the real world HP of a stocker is closer to 200, they are off by .053%. Their 300 HP corrected number would be closer to 271HP at the crank. Why the change? Marketing, miscalculating the driveline efficiency, marketing…. But Hurricane at least is in the same ballpark of stated numbers, and PEFI has a slightly different set of numbers but also a different approach to tuning. MCX has always said that any number over 250 HP with the stock turbo was questionable.
(Before I get flamed for talking smack about the tuners ——- I am not making any claims about what HP they are really producing)
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