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Old 01-28-2021, 05:53 AM   #17 (permalink)
AeroMcAeroFace
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Quote:
Originally Posted by aerohead View Post
2) engine accessory power absorption would be linear if belt driven
3) rolling resistance would be linear all the way to standing wave, beyond the performance envelope of the vehicle
4) I have 8% powertrain loss for an overdrive, manual transaxle powertrain, like the gen-I Insight. It's not as significant as BSFC, although, rates #2 in Sovran's research.
5) A BSFC map for the specific test vehicle would be welcome. This is the #1 bone of contention in Sovran's SAE Paper. It must be known in order to sort out any actual benefit of an aerodynamic modification, lacking gear-matching
6) Wind is really problematic. Datalogging would be imperative if one were to undertake testing during wind.
3) & 4) can't the powertrain loss be attributed under "rolling resistance" and be approximated to linear over the small amount of increase in speed though?

Quote:
Originally Posted by MeteorGray View Post
And if he sells a few books while doing it, good for him. The books' purchasers get the in-depth knowledge that only detailed books can provide, and those who don't buy the books still get a lot of free information given right here on this site and in the you-tube videos he has made.
Why are people complaining that he is writing and selling books? BMW use air curtains and no-one on here complained that it is unfair that they are making money off innovation. I think the problem is that some people on here, and I don't believe aerohead is one of them, just seem to despise Julian for pointing out flaws in their beliefs, whether that is the template misuse, the 12-degree rule of thumb or any other rule of thumb.
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