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Discussion Starter · #1 ·
According to simple mechanics:

Power = Torque * RPM

Using 217 ft-lbs. @ 4000 rpm

Power = 217 * 0.305m * 0.45(9.81N) * 4000/(60s) = 19.48 kW = 26.5 hp

which is awfully small (at 4000 rpm). What am I missing here?
 

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Discussion Starter · #2 ·
Nevermind, I found the discrepancy:

I forgot a factor of 2*Pi=6.28

The power then is 166.4hp which is much more reasonable.

Does anybody have the power and torque curves (dependence on rpm) for the wrx and 2.5rs to compare?
 

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ummm....WOW!

are you guys still in school? if not, what are you jobs?

i got a pretty good grade in physics last year, but reading this made me feel stupid...im 17

oh and did you find these formulas in a book?
 

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mario wait till your in college and you decide to be an engineer ive only taken one quarter so far and the amount you learn is overwhelming sometimes, and the only ME class i toke was mechanical systems, but it was such an interesting class, i enjoyed learning it because we got to learn how to figure out power output from an engine at any rpm with just knowing the pressure at top dead center, the pressure at bottom dead center and the displacement.

if you think these few equations is a lot wait till stuff like statics, dynamics, heat transfer, and fluid dynamics if you plan to be an engineer. thats when things start to hurt.
 

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mario wait till your in college and you decide to be an engineer ive only taken one quarter so far and the amount you learn is overwhelming sometimes, and the only ME class i toke was mechanical systems, but it was such an interesting class, i enjoyed learning it because we got to learn how to figure out power from an engine at any rpm with just the pressure at top dead center and bottom dead center and the displacement.

if you think these few equations is a lot wait till stuff like statics, dynamics, heat transfer, and fluid dynamics if you plan to be an engineer. thats when things start to hurt.
 

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the number 1 choice school i applied to is Cal Poly San Luis Obisbo.

I stated Civil Engineering as my major. originally i wanted to do mechanical engineering, but a lady's husband at my work is a mechanical engineer and he advised me not to do it becuase the industry is really bad right now. He graduated from USC and is really smart or something. but he said thers no work, and he's been out of a job for a while

what are you guys majoring in?
 

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Thinking Man's Engine
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It's true, the 2001 & 2002 job market does pretty much suck in general for engineers. You might want to consider a federal govenment job -- starting pay isn't that great, we'll catch up quick.

I'm a mechanical engineer for the US Army.

I work in TACOM-ARDEC (Tank-Automotive COMmand -- Armament Research, Development, & Engineering Center). I'm in the ARDEC side. I'm a project engineer on 5.56 mm rounds.

Heat Transfer is fun!!! ANd so is Fluid Dynamics.

Yes I'm still in school. I'm working on a Masters in Mechanical Engineering part-time.
 

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Well, i'll be damned! I've read many posts from clubrsx and haven't heard much going on there that intelligent. I guess there's a first time for everything. I just figured talking bad about the WRX was their only topic. Hey, the RSX Type S actually used to be one of the cars I was strongly considering buying. But between the people on their message board and the local dealers i've seen that the RSX Type S, isn't an option anymore. Ok, i'll quit ranting now, I just needed to get a cheap shot in.
 

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Discussion Starter · #11 ·
Thanks, Root!

Tan: The slight discrepancy between your number and mine is probably from the conversion of the power units between Watts and horsepower which I was not certain of (I hate these stupid non-standard units).

Mario: Everything is cyclical. There is no need to go for something that's hot now, because it might be different once you graduate. Just do your best on something that interests you.

BTW: I remember this stuff from Kindergarten, close to half a century ago.
 

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im currently at SLO Cal Poly, Mechanical Engineer(me) major. yea job oppurtonities are lower for everybody, but for an engineer, an ME graduate are the quickest to be picked up for jobs compared to other engineers. mario if you make it out to SLO join the fsae team ill be there. im off right now for vacation about to go back on sunday.
 
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