LifeOf350

Q50 has a muffler delete ONLY rest is stock.
Lexus has a custom megan exhaust + k&n intake.

mk416

Is the Q50 i4 turbo or v6 turbo?

UDel

Not in 2015. It had a 328hp 3.7l V6. Still pretty quick.

Has anyone figured out why the 2nd Gen IS350 and 3rd Gen GS350 were/are quicker then the 3rd Gen IS350 and 4th Gen GS350 in most tests? Is it just gearing/tuning? In most tests and avgs's they are around half a second quicker from 0-60, later year 3rd and 4th Gen IS and GS are slower too then earlier years despite more gears/hp bump.

arentz07

The RWD models have to shift twice before they get to sixty, which hurts them a bit. AWD models don't, but they are heavier and have a less aggressive final drive ratio.

EZZ

From a highway roll, they are about the same speed. The dig is where the 2nd gen has a speed advantage for sure.

JDR76

I think the answer lies in the transmission. You can see here that the GS350 didn't take much of a hit until they gave it the 8 speed. The 3rd gen IS350 RWD has that 8 speed, so that is where I place the bulk of the blame.

JDR76

LifeOf350

arentz07

That, and like JDR76 was saying, the 8-speed. The 8-speed causes the car to have to shift twice before reaching 60 MPH, which makes it slower.

Now if we are talking AWD, then it's strictly down to the weight as well as the final drive ratio. The AWD models use the same 6-speed as the 2nd gen.

UDel

Even the 6 speed auto's for the 4th Gen GS350 and 3rd Gen IS350 are a bit slower then the 6 speed auto 2nd Gen IS and 3rd Gen GS.

UDel

I think the 8 speed definitely has something to do with it, I remember test driving the 8 speed GS350 and it felt lethargic, slower then my 6 speed auto but even 6 speed 4th gen GS350's are slower then the 6 speed 3rd Gens, not by much but I remember test driving a 3rd Gen GS350AWD and was surprised how quick it felt, it felt like 5.3 seconds and quicker then my GS430 where my 4th Gen GS350 does not really feel any quicker then my 2nd Gen GS430. I also remember test driving a 2nd Gen IS350 and it felt really quick when I got on it, way quicker then my GS430 in the higher rev range, it felt like a 0-60 of 4.8-4.9 sec was doable which it did in one test, the 3rd Gens IS350 don't feel nearly as quick and I have never seen one do anywhere near 4.8 seconds in tests. Both sedans weights are similar from one generation to the other.

UDel

They don't weigh much more, less then 50lbs difference between generations with the same powertrains.

webra

EZZ

The stated Curb weights by Lexus say that but when C&D actually weighed them, it had around 3400 lbs for the 2nd gen and 3700 lbs for the 3rd gen (RWD). I think the 2nd gen is a smaller, lighter car so it should be faster for sure.

arentz07

There's also some throttle-by-wire lag going on, which I suspect the older gens didn't have. I have an AWD IS with the 6-speed. I let one of my friends test-drive it, and he noticed right off the bat. There's a delay from when you press the pedal to the car's response, which can make it feel sluggish. If you are in Sport mode it seems to be a little better, could be in my head though.