TF109B

7 gears aren't always going to give you better acceleration. The fact that the 458 has launch control and shorter gearing is the reason why it's quicker, SO FAR. Plus it's already in production. The LFA can rev to 9500rpm. But I think it's peak power comes at around 8700rpm? Corolla you even posted a picture here from lexus that said 0-60 in 3.2 seconds, did you not? Obviously Lexus is making this claim as somehow they have reached that. If this is true, only one thing can be said, Launch Control. If this is true and it hits 60 in 3.2, the power should take over from there and help it hit 125 in about 10 seconds. Didn't we see this in the first video with Tanner Foust driving it through the first 3 gears in about 10 seconds? If you know the gearing of the LFA and it tops 130mph in 3rd, it obviously was doing at least 120-125mph before Tanner short shifted 3rd gear to 4th.

05RollaXRS

No I think you did not understand. Although, you are right definitely launch control and the wing angle for LFA will go a long way in getting the best acceleration, no doubt and I certainly hope LFA will hit 0 - 60 mph in 3.2 seconds, I was only explaining why 458 is quicker than what most people expected. Simple answer is 9000 rpm redline and an insanely short final drive. There is nothing out of the ordinary about the power since it is dyno'ing at 450 wheel HP and 315 wheel torque.

7th gear will magically not improve acceleration, but it will facilitate more latitude in overall shorter gearing in every gear.

When I said 7th gears, I said to retain the top speed. What happens when you give shorter gearing is faster acceleration since there is more torque multiplication available in each gear, but downside is that every gear speed range reduces since you reach redline at a lower speed in every gear resulting in overall lower top speed.

It is hard to explain, but I hope you know what I am saying. LFA does have short gearing with a final drive at 4.3:1 which is why it blew away the R8 V10 in the acceleration test in the "Battle of the supercars", but 458 Italia is insanely short.

With a 7th gear and a 9000 rpm, shortening the overall final drive results in more acceleration per gear without compromising on the speed range of each gear and overall top speed.


I am sure, if LFA had 7 speed single-clutch transmission and had even a 4.8:1 final drive, it would be neck-and-neck with the 458 Italia from any gear at any speed (flexibility tests).

syzygy

This is a game lexus knows how to play well. It's the secret to why the IS350 performs far better (at speeds < 100 MPH) than people expect for a "mere" 300 HP car.

05RollaXRS

Funny how I super imposed a Ferrari 458 Italia dyno with the LFA MotorTrend dyno and was astonished at some results I observed.

LFA is actually making more high rpm torque than the 458 Italia. From 6000 - 9000 rpm, LFA retains its torque curve far better than 458 Italia, which starts to plummet far earlier at around 5500 rpm. LFA peaks later and attains its peak torque at 6900 rpm while the 458 Italia peaks at 3500 rpm. However, the high rpms which are used for all out acceleratiion, LFA has stronger torque available.

Comparing solely torque curve in their powerband, LFA seems to come out ahead since it retains its torque far better in the very high rpms. LFA is making roughly 8 - 10 ft-lbs of wheel torque more between 6500 - 9000 rpm.

Again, the only reason why 458 Italia is putting down those acceleration numbers is its insanely steep final drive.

syzygy

Interesting observation, I haven't looked at the dynos much to be honest.

I've always found it rather funny that many people who claim to be car gurus revere peak HP/torque so much. When will people realize that peak horsepower ratings are more of a marketing tool than anything.

Citing power to weight ratio by dividing weight by peak horsepower (or vice versa, doesn't matter) - while certainly more informative than simply citing peak horsepower - is still one of the most deceptive figures one can provide.

People should be much more interested in the integral under the horsepower/torque curve. Of course, at the end of the day, actual performance figures are what matter.

What I'll find often is the following -

Car A has peak horsepower of X
Car B has peak horsepower of X+20

Car A soundly beats Car B in some sort of straight line acceleration test, and Car B fanatics will rush in and call foul because in their amateurish minds there is no way for a car with X peak horsepower to beat a car with X+20 peak horsepower.

If Car A wins, it was just because car A got the jump, or car B didn't get a good launch, or <insert excuses X, Y, or Z here>

05RollaXRS

Exactly.

I can understand that because I drive a Yamaha built engine.

Peak torque and peak HP are only marketing tools. It is the overall torque curve that truly matters.

Funny how 458 Italia makes 398 ft-lbs of torque (315 ft-lbs of wheel torque), but it is only a spike at ~ 3800 rpm and then it gradually falls after that. After 5500 rpm, it starts to fall and gets to 270 ft-lbs of wheel torque at 7000 rpm and eventually to 250 ft-lbs of wheel torque at 9000 rpm.

LFA's torque starts climbing at 5500 rpm and reaches its peak of 285 ft-lbs of wheel torque at 7100 rpm and then retains most of this torque till 8000 rpm and then gradually falls to about 270 ft-lbs of wheel torque at 9000 rpm. At 7100 rpm, 458 Italia is making about 270 ft-lbs of wheel torque.

Case in point, LFA has a far better torque curve (more racing oriented that sustains itself) with a top heavy focus especially from 6000 - 9000 rpm while 458 Italia is better down low and midrange. At 9000 rpm, LFA makes 20 ft-lbs of wheel torque more than the 458 Italia. The Italia hits the rev limiter while LFA keeps going to 9500 rpm where the LFA still is making a healthy 250 ft-lbs of wheel torque that 458 Italia had at 9000 rpm.

TF109B

This is the picture I was talking about. It wasn't you who posted it rolla, it was another user, but you commented on it saying did anyone else notice the picture says 0-60 in 3.2 seconds. I'm not arguing with you about the gearing and such. The LFA makes plenty for a car it's size. If the Toyota Camry can hit 60 in 5.7 seconds making 268hp and 25xlb-ft of torque, the LFA should smoke the same tests since it weighs only ~200lbs. more.

05RollaXRS

Yes, I had posted by observation. I had requested someone (in particular, the owners-to-be to contact Lexus (or LFA tech) to confirm that this is now officially Lexus' new 0 - 60 mph, but no replies so far).

Could gengar or 07grIS350 confirm with their LFA consultant about this?? Thanks.

07grIS350

You could probably get an answer quicker by calling that Lexus dealer directly. The number is listed on the bottom of the ad. The LFA Web site states 3.6 sec with the equivalent weight of 2 people in the car.

TF109B

It's gotta mean launch control. Of course the euro mags will have you believe that the LFA is slow and that it'll only get there in 4.1 or 4.2, but they're wrong. They say the LFA's have launch control, but they're only pre-production cars. Why would Lexus/Toyota have a launch control system that starts a high-revving car in low RPMs? it doesn't make sense so it must be a precautionary measure or just a stationary L.C. That's my guess. Toyota even said that their F1 team had input on the car. So with that said, F1 cars have some of the best launch control systems in the world. Why would the LFA not have one that's at least half as good? Makes no sense. But this 3.2 to 60 does make sense.

05RollaXRS

http://www.youtube.com/watch?v=JsRxk...layer_embedded

05RollaXRS

Looks like there is a new prototype in the US following the yellow one (I think it is US):

http://www.youtube.com/watch?v=1Ky4i...layer_embedded

TF109B

Looks like it's black! Or dark gray. I like it the most so far of the prototypes we have seen. Hope more vids pop up of this car.

rominl

iTrader: (4)

i believe it's graphite color with white seats

maybe just another repaint. just saying

it was an event at lexus of glendale

TF109B

Could be another repaint. Unless we see otherwise I believe you. Do you think it's the white one that was previously the matte black one?