4 ms·
I always do a quick fact-check on any automotive engine claim: HP & Torque curves vs RPM should always cross at 5252 RPM. The one in TFA does not. \_(ツ)_/¯
by throwaway4dd5f 5y ago
I always do a quick fact-check on any automotive engine claim:
HP & Torque curves vs RPM should always cross at 5252 RPM.
The one in TFA does not.
\_(ツ)_/¯
- FPGAhacker 5y agoI didn't see any graphs in units of hp or ft-lbs. Do you have a link?
- reissbaker 5y agoThere's a torque-to-kilowatt graph roughly near the top of the article, and you can convert kw to hp by multiplying by 1.341.
- throwaway4dd5f 5y agoCrap, my bad, I didn't even realize the graph was using NM and kW. I'll go back into my cave now.
- gnopgnip 5y agox
- reissbaker 5y agoThat doesn't appear to be true? https://auto.howstuffworks.com/question622.htm https://auto.howstuffworks.com/question622.htm Mathematically, the OP seems to be correct.
- schwap 5y agoIt is mathematically impossible for the curves not to cross at 5252.
- murderfs 5y agoThe scales are different: torque is from 0 to 700 Nm, power is from 0 to 300 KW.
- cycomanic 5y agoIt helps not to work in ridiculous units. Power = torque x angular velocity So in this case let's take the position of the bend, where power goes flat (4000rpm, 250kW, 600Nm): P=4000 x 2x pi/60 1/s x 600 Nm = 251kW Seems to be correct.
- robomartin 5y ago> HP & Torque curves vs RPM should always cross at 5252 RPM Not really. First, this number only applies to imperial units. Second, axis scaling will move the crossing point. The only way this happens (provided we are talking about imperial units) is if the torque and power axis scales are explicitly scales such that the curves intersect at 5252 RPM.