ANYONE with a car should check this out

[rs_1101]

i just dug this up in another thread. i think this is an INCREDIBLE read for general car physics.. just look around

http://www.theoldone.com/

AND EVERYONE should read this one cuz i kno alot of people out there may not understand EXACTLY what the difference between hp and tq is

http://www.theoldone.com/archive/world-according1whatishp.htm

i spent most of the day reading this stuff. its awesome.

[Tenacious G]

yeah, i've continually seen posts referring to his Web site when discussing various car topics. very good information.

[Peking]

Looks to be a very interesting site, I will check it out in more depth later. Good find ;)

[2K2SilverSi]

It sounds like this guy knows what he is talking about to a point. Here is my conterpoint. A couple months ago Car and Driver ran an article about Diesels in Indy. They were talking about how diesel race engines were used by Cummings to attempt to prove diesels worth in cars. Diesels are known for there extreme amounts of low end torque and lack of high end hp. This is exactly what this guy is talking about. But when those indy cars were raced agains gasoline motors that made lots of highend hp and not so much low end torque the diesels couldnt keep up. In a related note the diesel engine did not make it through the whole race because it blew up, where as most of the gasoline motors did make it through. The diesel engine was the only one so it is not really fair to compair it but it is a statement since the diesel reved much lower than the gasoline motors.


Here is another example, Nascar engines vs the old CART engines. The nascar engines are big engines somewhere around 7.0L displacement V8's that make huge torque numbers and ok hp numbers (somewhere around 800 if I remember correctly) where as the CART engines are 2.8L V8's with around 45psi of boost that make around 900 hp but dont make that much more hp than an S2000. In a race, even if the vehicles weighed the same amount the Nascar cars might get the jump off the line but once the Cart engine got to redline (18,000rpm) in first that gap would be gone.


In the end there are other factors besides low end torque that can make a difference, if this wasnt true than we would be able to beat S2000's because we make more low end torque than they do (I am not talking about maximum torque but the ammount we make in the first 4000 or so RPMs of our powerband) we dont rev as high as an S2000 and we make less hp and the weight is nearly identical between the 2 cars so our car would be faster according to this guy but it isnt go figure.

[Tenacious G]

i think you're overlooking a few key points than just torque vs. torque for each car. first off, in your comparison between the S2K and EP, you also have to figure in gearing of the transmissions, traction and where the engine makes power in the power band ... i.e. the "transient response" of the engine. The S2K overcomes it's lack of low-end torque because the gearing ratios allow up shifts to stay the fat part of the engine's powerband -- therefore it is able to accelerate faster than the EP.

also, i think NASCAR race cars weigh more than twice CART or IRL cars do, so that cancels out the torque issue, IMO.

i also think you'll find that diesel, while a more powerful fuel than gasoline, still has too many limitations to compete with ethanol (CART engines don't run on conventional gasoline). so of course a diesel engine won't keep up with the ethanol engines because of the lack of their ability to hit RPMs.

[rs_1101]

u gotta consider he does not once talk about horsepower though. basically hp is related to the amount of TORQUE per stroke. if you have a motor that puts out more POWER(torque) at a lower rev than competition does at an EQUAL rev level, then you have some real power.
less engine motion = less wear

i thought this was interesting in light of earlier threads wheirein we discussed some mods that trade low end tq for high end hp. basically thats just saying, instead of me making power at 2k rpm, im making it at 6k. the question as to wheter or not youve gained any real power is different

[VividDreams]

umm, to correct you, NASCAR engines are not 7.0 L's, theyre more around 5.7(chevy,350c.i.), 5.8(ford,351c.i.)

but, point taken