I went to sema and ....
11-12-07, 07:59 PM
#16
Tech Info Resource
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Or, we could conclude, based on his comments, that he never actually drove the car. As most people agree, here, his statements are unreasonable.
I'm no expert in vehicle braking dynamics but it would seem to me that If the car is 1" lower, 90% stiffer in the front, 45% stiffer in the rear, this would significantly decrease nose dive and rear end lift, thereby, keeping more of the weight over the rear wheels and therefore decrease braking distance. Haven't they already recorded shorter stopping distances with the ISF than the IS350?
I'm no expert in vehicle braking dynamics but it would seem to me that If the car is 1" lower, 90% stiffer in the front, 45% stiffer in the rear, this would significantly decrease nose dive and rear end lift, thereby, keeping more of the weight over the rear wheels and therefore decrease braking distance. Haven't they already recorded shorter stopping distances with the ISF than the IS350?
BTW, both chassis have the same anti-dive and anti-squat geometry. Toyco's been doing this since the Supra in '93. They also both have the same "built-in at the factory" propensity for understeer to ensure no one gets hurt by tail happy escapades.
Also, your 90% stiffer also affects wheel compliance which extends braking distances over poor surfaces. There is no win/win here with stiffer or lower. The lighter car will stop in a shorter distance.
11-13-07, 02:50 AM
#17
Pole Position
They're not on the same tires. Put them on the same tires. They have the same EBFD, they have the same ABS, and the lighter car will stop shorter on the same tires. Guaranteed.
BTW, both chassis have the same anti-dive and anti-squat geometry. Toyco's been doing this since the Supra in '93. They also both have the same "built-in at the factory" propensity for understeer to ensure no one gets hurt by tail happy escapades.
Also, your 90% stiffer also affects wheel compliance which extends braking distances over poor surfaces. There is no win/win here with stiffer or lower. The lighter car will stop in a shorter distance.
BTW, both chassis have the same anti-dive and anti-squat geometry. Toyco's been doing this since the Supra in '93. They also both have the same "built-in at the factory" propensity for understeer to ensure no one gets hurt by tail happy escapades.
Also, your 90% stiffer also affects wheel compliance which extends braking distances over poor surfaces. There is no win/win here with stiffer or lower. The lighter car will stop in a shorter distance.
Look, all I'm saying is that weight and tires aren't the only thing involved, here. Suspension dynamics play a HUGE roll in braking distance. EBFD is designed to compensate for weight transfer during hard braking to keep all four tires at maximum brake force.The more balanced the total weight over all four wheels is, the better the braking and the more efficiently EBFD can work. I believe the ISF balances it's weight over all four wheels better than the IS350 during braking because of suspension dynamics. Again, I'm no expert but this seems like common sense. I look at it like this. Same suspension on both cars only one is tremendously stiffer, which means less weight transfer, which means more efficient EBFD, which means shorter stopping distances. (all other things being equal, of course)
11-13-07, 06:36 AM
#18
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I had a chance to drive the IS-F they had at SEMA. Did 0-60mph, 60-0 ABS braking, skidpad & slolam. Very nice car but IMO not worth the extra money compared to the IS350. FWIW, here are my opinions:
Acceleration: Below 50mph the accleration between the IS350 and IS-F is very similar and I could not note any difference. Above 50mph there is a BIG difference. Except for passing on the highway, there should not be much difference on the street. Also, the stock IS350 traps 102-103mph so it is not a slouch by any means. Below 50mph I was disappointed in the acceleration (probably traction control related).
Sound: Not as big a difference as I was expecting. The IS-F 5.0L V8 is not a high reving motor and has a very mellow tone that left me wanting more. The IS350 has a sharper sounding exhaust.
Transmission: Much better in the IS-F but there is still that ANNOYING 1 sec delay between when you pull the paddle til the car shifts. When it finally shifts, the IS-F shifts quicker and harder but not by much.
Acceleration: Below 50mph the accleration between the IS350 and IS-F is very similar and I could not note any difference. Above 50mph there is a BIG difference. Except for passing on the highway, there should not be much difference on the street. Also, the stock IS350 traps 102-103mph so it is not a slouch by any means. Below 50mph I was disappointed in the acceleration (probably traction control related).
Sound: Not as big a difference as I was expecting. The IS-F 5.0L V8 is not a high reving motor and has a very mellow tone that left me wanting more. The IS350 has a sharper sounding exhaust.
Transmission: Much better in the IS-F but there is still that ANNOYING 1 sec delay between when you pull the paddle til the car shifts. When it finally shifts, the IS-F shifts quicker and harder but not by much.
Wouldn't sport mode cure these issues? In sport mode, the transmission shifts in .1 of a second, it also opens a secondary air intake at 3600 rpm that makes the engine sound like a monster, and lastly, it increases throttle response so that the acceleration is just that much better.
11-13-07, 08:18 PM
#20
Are you really replying to my review of the IS-F and you have NOT even driven it? I do not appreciate the personal attacks and I would say your post is the ignorant one and you have no idea who you are talking to.
I am an automotive engineer with 2 advanced degrees from top tier engineering schools, 12+ years automotive engineering experience, and have designed and tested engine management systems for many platforms from Nissan to GM (C6Z06 & C6ZR1 ring a bell?) to Porsche. This includes much time spent track testing and subsequently fine tuning many NVH elements. During this time I also created my own automotive aftermarket company which has been in business for 5+ years during which time I have worked with several racing companies in optimizing automotive feedback for racing applications. So what are YOUR qualifications to make the statements you posted?
There have already been several other reviews by people who have driven the car that have similar feedback as myself. The entirety of your reply is just ignorant if you haven't driven the car, you should focus on your midterms.
Also note that I began my post with "IMO" it is not worth it. Your opinion may be different.
I am an automotive engineer with 2 advanced degrees from top tier engineering schools, 12+ years automotive engineering experience, and have designed and tested engine management systems for many platforms from Nissan to GM (C6Z06 & C6ZR1 ring a bell?) to Porsche. This includes much time spent track testing and subsequently fine tuning many NVH elements. During this time I also created my own automotive aftermarket company which has been in business for 5+ years during which time I have worked with several racing companies in optimizing automotive feedback for racing applications. So what are YOUR qualifications to make the statements you posted?
There have already been several other reviews by people who have driven the car that have similar feedback as myself. The entirety of your reply is just ignorant if you haven't driven the car, you should focus on your midterms.
Also note that I began my post with "IMO" it is not worth it. Your opinion may be different.
oh god, where to begin. i cant believe i am wasting my midterm study time to respond to this ridiculous post, but I can't help it because its so ignorant that its annoying.
similar handling characteristics and body roll? when one of the few things that all the different magazine/internet reviews have been agreeing on is that the IS-F has fantastic handling enough for many of them to say its more of a track car than a street car, someone like you who has absolutely zero credibility comes and says the stuff above. IMO the IS-F stock wheels are one of the best looking stock rims ever to be on a production car, and I think many people would agree. they certainly look MUCH better than a stock 18 on the IS 350. oh yes there IS a perceptible difference. REALLY? what did you lower your IS 350 with? because I have eibach sports on mine and to my knowledge there is absolutely NO WAY any reviewer is going to praise that cars handling if its doesn't have a better driving 'feel' than my lowered IS 350.
I'm curious as to know what kind of instruments are connected to your body for you to be able to gauge how much faster the IS-F is vs the IS 350 plus based on your judgement about the drive 'feel', I doubt its anything anyone should take seriously. If the lack of acceleration difference was the cause of traction issues, you would have still felt that the car was much more powerful.
another thing almost everyone who has reviewd the car have been agreeing upon is the sound of the engine. plus a whole lot of people including myself have heard the sound of the car either through the Lexus provided clips on the special IS-F site or even better the numerous videos of the IS-F being dynoed on youtube which clearly show that the car does sound COMPLETELY different from the IS 350/250.
LMAO @ "is not a high revving motor" and "mellow tone", duh the RPM redline is just 6800. and although some reviewers have mentioned that the low redline limited the enjoyment of the awesome sound after 3600 rpm, they still loved the sound nonetheless.
who really should take your post seriously when you say that the IS 350 has a shaper sound exhaust?
REALLY? the IS-F's braking is actually one of the THE MOST impressive thigns about the car and yet you claim that its "very similar"
you've got to be kidding me. the IS-F has achieved stopping distances of less than 110 ft from 60 mph which is outstanding and we have someone like you say thats its nothing special.
reviewers also have been raving about how the IS-F's brake did not fade AT ALL during extensive testing and we have someone like you who never even fully tested the brakes come out and say this.
those are COMPLETELY your OPINION. I am a IS 350 owner too and I think the IS-F looks MUCH better.
wow, you gotta be kidding me again... people like me who haven't even got to drive the car know (from videos and reviews) that the IS-F's 8 gear auto is as good if not better than advertised.
.........................please..............dont...................take.............this...........................guy seriously
similar handling characteristics and body roll? when one of the few things that all the different magazine/internet reviews have been agreeing on is that the IS-F has fantastic handling enough for many of them to say its more of a track car than a street car, someone like you who has absolutely zero credibility comes and says the stuff above. IMO the IS-F stock wheels are one of the best looking stock rims ever to be on a production car, and I think many people would agree. they certainly look MUCH better than a stock 18 on the IS 350. oh yes there IS a perceptible difference. REALLY? what did you lower your IS 350 with? because I have eibach sports on mine and to my knowledge there is absolutely NO WAY any reviewer is going to praise that cars handling if its doesn't have a better driving 'feel' than my lowered IS 350.
I'm curious as to know what kind of instruments are connected to your body for you to be able to gauge how much faster the IS-F is vs the IS 350 plus based on your judgement about the drive 'feel', I doubt its anything anyone should take seriously. If the lack of acceleration difference was the cause of traction issues, you would have still felt that the car was much more powerful.
another thing almost everyone who has reviewd the car have been agreeing upon is the sound of the engine. plus a whole lot of people including myself have heard the sound of the car either through the Lexus provided clips on the special IS-F site or even better the numerous videos of the IS-F being dynoed on youtube which clearly show that the car does sound COMPLETELY different from the IS 350/250.
LMAO @ "is not a high revving motor" and "mellow tone", duh the RPM redline is just 6800. and although some reviewers have mentioned that the low redline limited the enjoyment of the awesome sound after 3600 rpm, they still loved the sound nonetheless.
who really should take your post seriously when you say that the IS 350 has a shaper sound exhaust?
REALLY? the IS-F's braking is actually one of the THE MOST impressive thigns about the car and yet you claim that its "very similar"
you've got to be kidding me. the IS-F has achieved stopping distances of less than 110 ft from 60 mph which is outstanding and we have someone like you say thats its nothing special.
reviewers also have been raving about how the IS-F's brake did not fade AT ALL during extensive testing and we have someone like you who never even fully tested the brakes come out and say this.
those are COMPLETELY your OPINION. I am a IS 350 owner too and I think the IS-F looks MUCH better.
wow, you gotta be kidding me again... people like me who haven't even got to drive the car know (from videos and reviews) that the IS-F's 8 gear auto is as good if not better than advertised.
.........................please..............dont...................take.............this...........................guy seriously
Last edited by autovation; 11-13-07 at 08:20 PM. Reason: Added the "IMO".
11-13-07, 08:24 PM
#21
Did you have the car in sport mode?
Wouldn't sport mode cure these issues? In sport mode, the transmission shifts in .1 of a second, it also opens a secondary air intake at 3600 rpm that makes the engine sound like a monster, and lastly, it increases throttle response so that the acceleration is just that much better.
Wouldn't sport mode cure these issues? In sport mode, the transmission shifts in .1 of a second, it also opens a secondary air intake at 3600 rpm that makes the engine sound like a monster, and lastly, it increases throttle response so that the acceleration is just that much better.
11-13-07, 08:35 PM
#22
Again, have you driven it? There is a major difference in handling feel between a lowered IS350 and a stock one. MAJOR difference. There is a major difference in handling feel between a stock IS350 and stock IS-F. There is not as much of a difference between a lowered IS350 on 19's vs. a stock IS-F. That is my point.
BTW, mr. ________, please let me know what instrument you use to measure the feel of the car? I used "actually driving it".
I can afford the IS-F but it will not be the replacement for my IS350. At that price point a 2yr old M5 looks pretty attractive.
Maybe I went into the IS-F driving experience expecting too much. I am very happy with the IS350, it truely is a great car. Based on that I couldn't wait to drive the IS-F. It sounds like from what you guys are posting that you are expecting the same things I was. I hope your expectations are satisfied because mine weren't. If I could only have 1 car, the IS-F would be on my radar screen.
BTW, mr. ________, please let me know what instrument you use to measure the feel of the car? I used "actually driving it".
I can afford the IS-F but it will not be the replacement for my IS350. At that price point a 2yr old M5 looks pretty attractive.
Maybe I went into the IS-F driving experience expecting too much. I am very happy with the IS350, it truely is a great car. Based on that I couldn't wait to drive the IS-F. It sounds like from what you guys are posting that you are expecting the same things I was. I hope your expectations are satisfied because mine weren't. If I could only have 1 car, the IS-F would be on my radar screen.
These people comparing the 350 to the isf are just complete ________ I cant even begin where to start, keep telling urself ur 350 is just as good as the isf and maybe even better than it cause you have it lowered LMAO . . . you gotta be kidding me . . .
Btw whoever asked that question about what instrument he used to measure the feel . . . its this new dyno they have, its implanted in your *** - BUTT DYNO
And whoever keeps using price justification as the reason they wont be buying it and are saying just go get the m3, your even more dumb than the other guy - the isf being faster than the m3 in accel, (c&d who properly drove the car and the amci test driver test verified) and your baggin on it that its only alil faster than the 335i, then how can you justify getting an m3 if the 335i chipped is only about .2 seconds slower to 60 than the m3 . . . (mag tests) you gotta be kidding me.
Btw whoever asked that question about what instrument he used to measure the feel . . . its this new dyno they have, its implanted in your *** - BUTT DYNO
And whoever keeps using price justification as the reason they wont be buying it and are saying just go get the m3, your even more dumb than the other guy - the isf being faster than the m3 in accel, (c&d who properly drove the car and the amci test driver test verified) and your baggin on it that its only alil faster than the 335i, then how can you justify getting an m3 if the 335i chipped is only about .2 seconds slower to 60 than the m3 . . . (mag tests) you gotta be kidding me.
11-13-07, 08:44 PM
#23
I thought the IS 250 and the IS 350 were the same until I jumped into the IS 350. I'd rather pay the extra money to get what I want. My preference for having more power is what made my driving experience in the 350 all the more fun! 100 more ponies does make a difference, it just depends on what you value most in a car. Live and be happy..you only live once! 
11-13-07, 08:49 PM
#24
Look, all I'm saying is that weight and tires aren't the only thing involved, here. Suspension dynamics play a HUGE roll in braking distance. EBFD is designed to compensate for weight transfer during hard braking to keep all four tires at maximum brake force.The more balanced the total weight over all four wheels is, the better the braking and the more efficiently EBFD can work. I believe the ISF balances it's weight over all four wheels better than the IS350 during braking because of suspension dynamics. Again, I'm no expert but this seems like common sense. I look at it like this. Same suspension on both cars only one is tremendously stiffer, which means less weight transfer, which means more efficient EBFD, which means shorter stopping distances. (all other things being equal, of course)
This is correct in general. I want to make 2 comments here:
1. You won't notice the difference in IS-F and IS350 braking when you are driving the car on the street. From normal street speeds the difference in braking is probably less than 2 feet (if even that?).
2. The IS350 I am using for the comparison has a wheel/tire package with wider GSD3 tires and subsequently more braking power. Does it make up for those couple feet? Who knows, testing would need to be done. Note here, NEVER buy cheap tires.
11-13-07, 09:13 PM
#27
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Yes it was in sport mode. The actual shift itself is faster than an IS350 but there is still that same delay between when you pull the paddle and when the shift actually begins. It doesn't even feel as natural as the one on a Ferrari 360. Although the Ferrari 360 shifts "slower", it has a smaller delay after when you hit the paddle until the shift begins.
11-13-07, 09:49 PM
#28
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Automobile magazine states the following:
"Unfortunately, the transmission uses the same curiously spaced gears as it does in the LS460. To wit, first, second, and third are so far apart that you're constantly wishing for another couple of gears in between, especially on slow, twisty roads. Conversely, the higher gears are so closely spaced that half of them seem superfluous. Case in point: when you are cruising at 50 mph in eighth gear, you need to pull the left gearshift paddle six times to downshift to your optimum passing gear. This confuses the transmission and results in no additional forward progress for what seems like an eternity."
"The solution is to drive in the normal automatic mode, which allows the transmission to perform a magnificent eighth-to-second downshift at the nudge of your right foot. In automatic mode, though, there is no permanently locked torque converter and no lightning-quick shifts."
Basically, it sounds like the automobile magazine editor is saying that it has to be in the manual mode to get the quick upshifts, and that the downshifts confuse the transmission in passing maneuvers. Is there any truth whatsoever to these statements?
Here is a link to the full automobile magazine write up:
http://www.automobilemag.com/reviews...s-f/index.html
"Unfortunately, the transmission uses the same curiously spaced gears as it does in the LS460. To wit, first, second, and third are so far apart that you're constantly wishing for another couple of gears in between, especially on slow, twisty roads. Conversely, the higher gears are so closely spaced that half of them seem superfluous. Case in point: when you are cruising at 50 mph in eighth gear, you need to pull the left gearshift paddle six times to downshift to your optimum passing gear. This confuses the transmission and results in no additional forward progress for what seems like an eternity."
"The solution is to drive in the normal automatic mode, which allows the transmission to perform a magnificent eighth-to-second downshift at the nudge of your right foot. In automatic mode, though, there is no permanently locked torque converter and no lightning-quick shifts."
Basically, it sounds like the automobile magazine editor is saying that it has to be in the manual mode to get the quick upshifts, and that the downshifts confuse the transmission in passing maneuvers. Is there any truth whatsoever to these statements?
Here is a link to the full automobile magazine write up:
http://www.automobilemag.com/reviews...s-f/index.html
I agree with the shift delay from 1 - 2, for some reason when you pull it at like 6500 it waits till it bounces off the rev limiter to shift, but no way in hell was there a shift delay through the rest of the gears, and ya ive driven it . . . it was instant, you pull it, you are in the next gear, it knows your going to change gears. I thought my modified 4r70w shifted quick and after going through alot of videos of my shifts and comparing it to the isf shifts its day and nite
11-14-07, 02:00 PM
#29
Lexus Connoisseur
Exactly, which is why Lexus gave us plenty of seat time at Laguna Seca and a few hours behind the wheel on regular streets of Carmel, Monterey, and the Big Sur area.
11-14-07, 02:04 PM
#30
Lexus Connoisseur
Too add to this and is a tidbit of what i'll be talking about in my write up shortly, the good usable gears on regular city driving in "M" mode is 2-5th. Anything above 5th is too low for acceleration or passing at city cruising and even highway speeds. There is no reason to be in 8th gear at 50mph unless you are looking to save gas. In full auto mode, the tranny keeps the shifts seamless and smooth, you really don't need to worry about what gear it's in.