Ford Racing 2011 Mustang 5.0 supercharger - 624 horsepower!!!
08-21-2010, 06:02 PM
#21
I agree with you that HP is useless without torque (just look at the Mazda RX8), but the numbers don't have to be similar to be an efficient combination. It all depends on what the vehicle is used for. Take the new 6.7 liter powerstroke for example. It has about 400hp and about 750 lb. ft. of torque, but it won't be winning any speed contests. Or for the other extreme, consider a Prius. 300 lb. ft. of torque at ZERO RPMS (not a typo), but only about 100 HP. Again, won't be winning any speed contests. I know people like to use the famous old quote, "HP sells cars. Torque wins races," but the truth is you can't do much without enough of both.
HP is nothing more but torque at RPM. And if the 6.7L Superduty Powerstroke diesel engine could turn 7000+ RPM and hold onto that 700+ ft-lbf torque, when you do the HP calculation, you will easily see that Powerstroke diesel hitting well over a thousand crank BHP!
Again, going with the definition of HP, the Prius electric traction motor (300ft-lbf at zero RPM) makes ZERO HP despite creating a butt load of torque at the instant current is applied to the traction motor! LOL
For HP to exist, you not only must have torque, but you must also have RPM. Torque in combustion engines, since it is impossible for combustion engines to create torque at zero RPM (current engine designs), our reciprocating combustion engines will always be making some sort of HP when the crank is turning.
In all, I totally agree with what you said; HP sell cars but torque wins races.
And when it comes to this supercharger, I hope it is a considerable torque curve and not one like one of those pip-squeak 4bangers that has an advertised 700 crank BHP but the torque is only like 300 crank ft-lbf max (i.e. the 4-banger is only able to make 700 crank HP because it turns insane amounts of RPM, 8000+ RPM, but it still makes Mickey Mouse torque throughout the entire torque curve).
08-21-2010, 06:16 PM
#22
I can only guess that you haven't seen a twin screw dyno sheet before. Torque is flat and usually at 90% of max by 2500 rpm and stays that way through to redline. I could post up one of mine for a reference but it's for a 3v 4.6 so it wouldn't be apples to apples. A friend of mine just bought a 2011 GT Premium with the Brembo package for a little under $29K. Add the FRPP/Whipple package for $7200 or so and he's got a very powerful car for under $37k. I can't think of anything that would come close for that price range.
For over $7000, I would expect nothing less. Aftermarket superchargers have become so damn expensive from what they used to be 5 years ago, it is clear the price increase over the years has not been in line with inflation, but the supercharger cost increases have been significantly more tan inflation.
08-21-2010, 11:21 PM
#26
5th Gear Member
Join Date: Jul 2006
Location: New Orleans
Posts: 4,491
People, it's a twin screw. I'm willing to bet my ***** that torque will be near peak at low RPMs and remain linear until redline. If it were a roots or centri, then the torque curve would be gradual, but the main selling point of a twin screw (and the reason it cost more than roots and centri kits) is the high flat torque curve. It will chew up tires, no doubt.
08-22-2010, 12:01 AM
#28
6th Gear Member
Join Date: Nov 2007
Location: Montaner
Posts: 6,193
08-22-2010, 12:59 AM
#29
5th Gear Member
Join Date: Mar 2007
Location: Florida
Posts: 3,062
While looking at the list of threads in the forum you want to make a thread in, hit the "New Thread" button near the top. If you are viewing a thread, all you'll get is the "New Reply" button.
