TF109B

The guys has a youtube channel and has videos of the same day with the Carrera GT getting passed by a 599GTO on that back straight. It launched a little late, so it wasn't really a fair drag race though- but the Ferrari was clearly faster.

05RollaXRS

I think LFA was using launch control definitely in that video. Even before the end of second gear, LFA was 5 - 6 car lengths ahead of the IS-F meaning a lot quicker 0 - 60 mph. Plus the surface looks very nicely grippy.

flipside909

Do you know that for a fact they were using launch control? Because from experience driving both cars, my IS F has 8 gears to row through, where the LFA only has 6. The first 3 gears in the IS F are very short and as you may know this trans is the same one from the LS460. The LFA is obviously quicker because it has 136 more horsepower, geared well and is lighter than the IS F. A good driver can launch the LFA without the use of LC.

05RollaXRS

I said 'I think' since it took off very quickly.

From what I understand, off the line IS-F has all of its torque come at much lower rpm than the LFA so without launch control on LFA, IS-F can edge out the LFA for a few split seconds before the LFA gets on full boil and blows past it.

flipside909

I think you need to drive the LFA first before you can make these assumptions.

TF109B

Regardless of what people drive or have driven, the thing bolted away from the IS-F pretty good. Isn't this LFA owned by Lexus? Maybe they brought both out for 'test drives'?

05RollaXRS

I don't believe the blue LFA is owned by Lexus Europe. I think it is privately owned.

MRxSLAYx

You really only have 6 gears that can be used for performance in your F. I wouldnt call the gears short, but its all relative.

I do believe that a stock ISF should see the taillights of an LFA the second the lights turn green though.

05RollaXRS

LFA gearing is considered short. The axle ratio is very low. The total final drive ratio is 4.3:1 once reduction from the counter drop gear ratio 1.26:1 is factored in. Ofcourse, the speed range per gear still is very broad in LFA due to the 9500 rpm rev limit.

flipside909

Good point because the only usable gears i've been able to use at Laguna Seca, Fontana and Infineon have honestly been 1-4...very seldom 5th on a long straight...IS F that is.

motohide

Well, it's more fun to play with 8 gears in the ISF and LS460 than fewer...LOL!

Ok on the topic of 8 speed box in the IS-F.

Actually all jokes aside, the IS-F has a pretty broad range of gears to suit the extremely torquey V8 that's simply over-sized for a car this weight. However, with 8 speeds to play, the ISF has the merit of having a VERY tall highway gear at the top range for efficiency as much as allowed for engine this big, as well as a very close ratio box for track use from 2-6th that's totally capable. I think all it needed was 7 in this case, but I guess for a very limited run of IS-F, cost of making a different box was out of the question, so the low 1st gear remains, as only needed for the LS460's heavy body to launch and perform to rivaling AMG Mercedes...while being superfluously low for a IS-F. That's the only conclusion I can come up with...

The AA80E is still, a very refined and durable transmission and it's shifting mechanisms are both extremely smooth and quick, making it ideal for almost any application that requires comfortable shifts in a roadcar, as well as performance situations where driveline shocks can be reduced greatly by having close ratios and well controlled power transfer timing created by the converter, actuators, and software programming of the ECT. It was a perfect choice for a IS-F...in my view, though we all like to brag about it more it it actually had the more "media hyped and exotic SMG type" box like the LFA, which is very costly but yes, it does have merits in a car that is more fine focused in purpose than a IS-F.

jpvarghese

iTrader: (1)

Do you think a paddle shift like the LFA's would suit the IS-F better for performance driving?

motohide

I would think that it will make some difference in durability and some performance specs, but in actual driving feel, both systems can be tuned to similar feel if there are enough resources to re-tune them to the ISF. Ultimately with any automobile interface of man and equipment though, depends on the driver mostly, and what I personally enjoy is either system, as long as the unit is integrated well, and electronics, hardware and software, and equipment has characters that make for predictable and enjoyable feel, and allows drivers to make less errors and have more fun.

flipside909

You mean the fixed paddle shifters on the steering column the LFA has compared to the paddles affixed to the steering wheel? It really all depends on the driver like Moto mentioned. I'm pretty used to how the paddles are on the IS F, but I can see where a lot of people complain about it especially when you have the wheel turned hard or go lock to lock, its crucial to know the orientation of the shifters when maneuvering. Its difficult to do that with the IS F.

motohide

Another reason for the LFA paddle being fixed location may be because a car that is RWD and well balanced and forgiving, is more often steered partially by the rear, and most hard cornering, many times, are in a mild state of 4 wheel drift, making the steering wheel stay at a fairly neutral position after corner entries. Combine that with the fact that the LFA has much taller steering gear (quicker ratio lock to lock) I found the LFA to not have high degree of steering input most of the time on the track doing hard exercises. Still, in town, under normal traffic, the steering will move much more and that may present inconveniences for the driver to reach for the shift paddle.