I mean even the pro 5.0 guys are using lower displacement turbo motors to build hp slower (intentionally dropping torque) and maintain traction (or what ever the 10.5" tire class is)


the only fast cars in racing that make shit tons of torque too are top fuel cars because its hard to rev a bottom end with that much weight very high but it needs to have that weight to hold the power they make.

even nascar.... i mean dale jarrett's car dynoed 799 hp at the wheels at over 9k rpm the other week.

[Edited on April 1, 2007 at 10:32 PM. Reason : .]

4/1/2007 10:31:12 PM

Quote :

"using lower displacement turbo motors to build hp slower (intentionally dropping torque)"

are you saying keeping a lower rev limit? many of the dyno charts ive seen on turbomustangs.com show peak numbers before/around 6000rpm

what are you saying- just an intentional de-tune?

[Edited on April 1, 2007 at 10:51 PM. Reason : -]

4/1/2007 10:49:15 PM

he made a pointless point. yes, they detune for torque/low end power some because of the tire width limitation. it has nothing to do with the discussion at hand.

4/1/2007 11:13:30 PM

haha not really de tune... they build in intentional lag to make a very top heavy motor to launch softer and build hp as it goes down the track (they're not allowed to vary boost in most cases)

4/1/2007 11:24:56 PM

Quote :

"peaktorque horsepower don't mean shit. "

is what i was trying to get across

Quote :

"horsepowertorque, produced over a useable rev range, is all that matters"

both can be used in thei sense i guess. either of them can be derived from the other, but useable range is the key phrase. high torque over a wide rande of engine speed can often do more work than high horsepower engines with lower torque but high engine speed if that makes any sense.

that's a large part of why twins are so popular in motorcycle racing, and that's why huge ass diesel trucks can often smoke a car with a higher hp/weight ratio

[Edited on April 3, 2007 at 11:19 AM. Reason : /]

4/2/2007 2:34:40 AM

I will take a well balanced hp/torque motor anyday of the week over just a high HP motor

for most any situation

4/2/2007 8:42:34 AM

since no one mentioned it is AREA UNDER THE CURVE THAT MATTERS

what igor doesn't seem to understand is that if that area is from 6000-10000 rpm you'll have just as fast of a car as if it were from 2000-5000rpm...if not a faster one. but the torque that the first car has will still be much less than that of the second.

i don't care where the power is as long as i have 3500-4500 rpm of it to play with.
also the car has to be setup for the kind of power it has.
if you had a 5.XX axle ratio on a torquey low reving car its going to shift every second and run out of top end. just like if you have a 2.73 on a high reving car... it will take 10 min just to get into your powerband.


[Edited on April 2, 2007 at 9:15 AM. Reason : .]

4/2/2007 9:11:50 AM

^ ha

those ranges arent the same

4/2/2007 9:29:30 AM

Quote :

"since no one mentioned it is AREA UNDER THE CURVE THAT MATTERS"

cause everyone with a basic knowlege of calculus would is assumed to know this, let alone a engineering students/graduates.

btw the ticky question is, WHICH CURVE?

also torque at the crank and torque at teh wheels are two comletely different things, and i am not talknig about drivetrain loss.

Quote :

"if you had a 5.XX axle ratio on a torquey low reving car its going to shift every second and run out of top end. just like if you have a 2.73 on a high reving car... "

why are those cars geared lower? to have more TORQUE at the wheel at any given wheel speed.

4/2/2007 1:38:45 PM

no shit, but that's the whole point. torque at the engine doesn't mean anything. it's all taken care of in the gearing. the only thing that matters for the engine (in terms of hauling ass) is for it to make lots of power over a useable (few thousand rpm, give or take depending on the # of gears and how quickly you can shift them) rev range.

the thing that propels a car forward is the force applied between the tires and the ground. What matters is the rate at which this force is applied. Torque produced at the engine is meaningless, because it's going to be multiplied by some coefficient through the transmission and final drive, and those ratios are going to be optimized for the particular setup (based on whether the engine makes lots of torque or only a little). In the end, the only thing that matters is power.

(and again, I'm not saying that grocery getters and pickup trucks should have engines with sportbike-like power delivery...I'm just saying that when being fast is what matters, you are really only concerned with power...which is why sportbikes have, well, sportbike-like power delivery! they are designed with ultimate performance as basically the ONLY criteria.)

[Edited on April 2, 2007 at 2:06 PM. Reason : asdf]

4/2/2007 2:04:49 PM