Quote:
Originally Posted by KennyPowers
well, to my understanding torque values are important. torque is what power is calculated from on a dyno, right? tq x rpm / 5250?
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Not on chassis inertia dyno.
Power is measured/calculated based on the ability of a powertrain to accelerate a rotating mass. The "Wtq" value is then derived from the formula you quoted (Wtq=Whp*5252/Engine RPM). Dividing by the wheel RPM would yield the true wheel torque value.
Quote:
Originally Posted by KennyPowers
so, higher torque means higher power, therefore a lot of torque means a lot of power. stronger low RPM torque, and still holding strong tq (almost 300 to the wheels) at redline is a good recipe for strong power.
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Torque at RPM is relevent to performance, hence power. But I agree, the more torque an engine is able to produce at a given RPM, the more power it makes at that RPM. But why bother looking at the torque value when the power tells the whole story
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Quote:
Originally Posted by KennyPowers
gearing helps some, sure, but there is no way that an e92 m3 feels strong whatsoever in 6th gear despite the shorter gearing. it may have short gearing, but it makes very low tq and at lower rpms, it just doesn't calculate to a lot of power. the e92 m3 spends almost half its rpms under 250 whp.
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My example of the E9X M3 vs E39 M5 was just to show how gearing is important when looking at torque figures; and JoeFromPA can relate to the M5
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At 2000RPM in 6th, an E9X M3 makes more actual wheel torque than a 335i (~825lb-ft vs ~800lb-ft), yet 335i owners keep saying that the S65 lacks low end torque
. Race an M3 and a 335i in 6th gear starting at 50mph and it will be pretty even at first and the M3 will eventually pull ahead. Sometimes it is a question of prespective, since the S65 pulls so much more when downshifting, it may feel week when kept in gear.
The more power an engine can make over a broad RPM band will translate to better performance. And that seems to be the strong suit of the new S55
