Is300H-Maximum Speed Limitation

Rabbers · August 30, 2014

I apologise if this post gives the initial impression of being written by a fan of

Top Gear (which I nowadays rarely watch after it became little more than a comedy

show). I confess, though, that when I was thinking of buying my 300h, I was worried,

having once been a disciple of Clarkson, about the limitation of the speed to 200kmh,

this being the minimum figure Lexus thought it could get away with without over-

diluting the car's intended sporty image. My concern arose not from practical every-

day considerations but from the idea that my very occasional therapeutic need for

speed would become no more than a nostalgic memory. I need not have worried.

Recently, on a fast, straight and slightly downhill stretch of German autobahn along

which I always look forward to driving whenever I get the chance, regrettably only

two or three times a year, the 300h nudged 215kmh (maybe a real 205kmh) before

the needle stabilised. That I used to touch 220-230kmh (maybe a real 215kmh) in

a previous-generation 250 on the same piece of road is less important than the

seamlessness and linearity of progression with which the 300h reached its top

speed. The 250, by contrast, tended to struggle after the 200kmh mark, almost

inviting you to ease off. Although the 300h's performance did not get me to yelp

and whoop as members of the Top Gear team and their stooges are wont to do

when stamping on the loud pedal of cars few of their audience will ever drive, I was

nevertheless deeply impressed by the beautifully engineered marriage between the

engine and the CVT, and cannot understand why the latter has been so maligned.

I also suspect the 300h got to 200kmh at least as quickly as the 250, and certainly

less noisily, but I won't even try to guess the comparative times.

Knowing full well that speeds of over 200kmh are in any case silly, being not only

uneconomic but also dangerous when maintained for any length of time on a public

road, even where there is no speed limit, and having at the same time observed

that the 300h's top-end shortfall of 10% in respect of the 250's speed in no way

caused the hair on my chest to thin out and wither, my sole ground for disappoint-

meant was the increased frequency with which I was flashed by big Germans in the

overtaking lane. My consolation was that since they were on their own home turf it

would have been rude not to let them pass. Were I a few years younger and living

in Germany, though, I would probably be looking at ways and means of financing

the purchase of an RC-F....

MarksaCox · August 30, 2014

Lucky you to be able to drive it in German land.

Sent from my Iphone using Lexus OC

Exdee · August 30, 2014

Interesting post. I drove both the 2nd gen IS250 and the 3rd gen IS300h on the Autobahn this month so here's my take on them.

The IS300h definitely had less road noise then the IS250 which could be due to better refinement and newer tyres but I found the engine too noisy especially en route to Austria where it starts to get a bit hilly. The Autobahn is generally littered with these 2.0 - 3.0 litre diesel engines which have a ridiculous amount of torque (the ones that flash you) so if you want to stay in the fast lane you generally have to floor your car. I went up to 180 km/h on the IS300h (was being cautious as it wasn't my car) but yeah it was great apart from the engine feeling like it would pop under hard acceleration. I am sure if I drove more sensibly and accelerated gently the engine noise would not have been an issue.

Getting back into my IS250 I found it a bit sluggish at low speeds (the hybrid motor definitely gives the IS300h an edge). I could instantly feel the road noise was higher on the Autobahn in general, except in parts where they have done a great job on the road and it is unbelievably smooth and quiet! I did not find the engine noise to be excessive even when thrashing the car (maybe my ears did not mind the sound of the V6). I went all out on my car. Yes, I kid you not. 260 KM/h. It is not limited to 140 MPH as Lexus claim it to be which I found surprising but hey I did not mind. I was very impressed especially considering this was on a slight incline!

The actual pull from 80 - 130 MPH was great as this was in the 4th gear which has great power delivery across the range. There was a brief pause when the car switched to the 5th gear which felt like that was it but I think it was due to the revs falling into to a range where the power delivery isn't that great. It felt like it started to pull again after it reached a certain point on the rev counter.

I should probably also mention that after reaching the top speed I had to brake to a complete stop because of an incident on the road ahead. I did manage to stop in time without engaging the ABS which probably means it was a safe stop after-all. But the deceleration wasn't as quick as I would have liked it to be. The fact that I have the low dust pads which are a less abrasive material probably didn't help either.

But still, It was my first time on the Autobahn and I think it will be memorable. I remember smiling from end to end and being immensely proud of the vehicle. Having said that I should probably stress that one should not get too excited and go over the top especially when going downhill. Accelerating is easy, It's the stopping part that can be difficult. :)

Rabbers · August 31, 2014

Jami:

260kmh in the present-generation 250 is amazing. In the previous-generation 250, of which I have

owned two, and which, if I remember right, also had a declared top speed of 225kmh (=140mph), I

never got near this figure even on the most welcoming stretches of autobahn. I fully understand

your reluctance to push a car that is not your own to its limits but, as I said in my post, the 300h

showed no strain at its declared limit of 200kmh and beyond, the way to get to it being to gently

but firmly accelerate until the pedal is almost floored and then finally floor it upon the needle's first

signs of hesitation around the high 180s/low 190s.

As regards the 300h's ability to brake from high speeds, I had been a little concerned after one

leading Italian motor magazine (Quattroruote, October 2013) declared the braking distance to a

stop from 160kmh, which is the cruising speed I generally aim for on the autobahn, to be 113m

with a light load, while another (Auto, August 2013), without specifying the load, said 101m, which

is a more comforting figure but still worse than the average for the class. However, whether my

own personal reaction times were good or average or poor when the need occurred to brake to a

standstill or near-standstill from cruising speeds because of incidents or queues ahead, I objectively

judged my distances on 18" Turanzas, 225/40+rear255/35, with 17000km wear on them, to be no

worse and possibly better than those of most of the cars I encountered behind and ahead of me.

Stability of line, on the other hand, I found to be excellent from even higher speeds, and this gave

me a higher degree of confidence, especially in wet conditions, than I ever felt in the 250. As

regards steep and winding downhill stretches where there is a genuine need to slow down to,

and maintain, the limits of 120kmh or sometimes 100kmh because of the danger from the surprising

number of cars that have difficulty in keeping to their own lane (and where I surmise that brake

failures are not unknown), I found the roadholding and the speed and precision of the steering

response to be beyond reproach, and if the steering itself is said by some critics to lack feel, they

are either talking nonsense or I have gotten so accustomed to this "defect", if it exists, that I no

longer notice it.

I notice you mention low-dust brake pads and the possibility that they might negatively affect

deceleration. I have no experience of them, but do you think they are worth fitting if only on

cosmetic grounds?

Exdee · September 2, 2014

I notice you mention low-dust brake pads and the possibility that they might negatively affect

deceleration. I have no experience of them, but do you think they are worth fitting if only on

cosmetic grounds?

It's actually a bit controversial. Whilst they do help keep the dust away the initial bite is lost quite significantly.

If you like progressive braking then you will love them but if you brake at the last minute then you will probably feel uneasy with these.