Will1991

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@flipside909 , this new IS500 F Sport has the same old tech has the RC F, it's literally the same engine/lower spec transmission/lower spec brakes. As far as the chassis reinforcement goes, just for being a coupe it's easier to make it stiffer... And the RC F doesn't even fold the rear seats because of extra reinforcements (like what happened in the new ES).

As for the construction itself, all 3 cars (IS/RC/GS) are based on the same New N platform, so it's intended to share some components and to easily adapt between them as seen in the 2021 IS that have the same front casting from the older GS/RC.

If you ask me which one, I would have, it would be the IS because I’m in love by the design and the whole idea of the compact sports sedan that can be driven hard and take the whole family on vacations. But we can’t deny, right now, the RC F is superior on track, even Lexus says this IS 500 F Sport is not a full-F.
 

flipside909

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LIke I said, you continue to misrepresent the facts. The RCF also has a 10-point brace in the rear that the IS500 F-Sport does not have. It also has shock tower braces in the front that the IS500 (or the GSF) did not have. All of those chassis strengthening were done in order to make it worthy or racing homologation, which is what it was built for. Those are Yaguchi's words. You are saying it is front heavy, but when you look at the engine placement of the RCF. The weight distribution is the same 54/46 for the LSD and 53/47 for the TVD one. Understeer is not something reserved for the RCF. The GSF has understeer as well. It is with TVD, you are able to get the rear end to rotate easily.

I drove both GSF and RCF before I made my decision. Like I said, GSF felt very big, bloated and much softer compared to the RCF, which is why I decided not go with my first option of getting GSF. The size is simply something you cannot mask. It is just physics. You are critical of the TVD, but is what makes the GSF handle much better than it should. All of the reviews give TVD the credit. There is no LSD GSF, but it would have been very easy to prove, if it was.

I have driven the 2016 - 2017 IS350 F-Sport extensively back in the day and the new IS350 is a modification of the same chassis. You seem very impressed with it, but C&D was not impressed with the handling at all calling the chassis 'flimsy' and saying even a Camry TRD had better handling than it.

Again, like I said before, RCF with TVD had a lateral grip of almost 1.00g. No Lexus this side of the LFA has accomplished it so far and until we see some actual numbers, those are just your biased claims.

I'm not misrepresenting facts. This is from my own driving experience on public roads and actual tracks. My research is not just from magazine articles and forum posts. As for chassis rigidity, There's a reason why the GS F doesn't have shock tower braces, the chassis was rigid to begin with (L10 GS Chassis).

There's no arguing the GS is larger than the RC F. The GS chassis in general is a better built chassis than the RC because it was designed entirely from the ground up, not a mix of other chassis. I had a 2015 GS 350 F SPORT...and loved it. I think it's more fun and engaging to drive than my RC F. Now if the GS F had a Torsen LSD option, it would have been the obvious choice. Since the IS 500 F SPORT Performance has it...it definitely has my interest.

I don't really care about skidpad testing or magazine reviews, I don't base my decisions on magazine racing. Ultimately it's what I want to buy...and how the car makes me feel. Great the RC F has 1g of lateral grip...how does that improve your drive to work or the grocery store? The modifications of the 2021 IS chassis are tremendous. Lexus is about continuous improvement and the new Lexus Driving Signature proves that. I've driven the LFA on the streets and the track...how about you?
 

flipside909

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@flipside909 , this new IS500 F Sport has the same old tech has the RC F, it's literally the same engine/lower spec transmission/lower spec brakes. As far as the chassis reinforcement goes, just for being a coupe it's easier to make it stiffer... And the RC F doesn't even fold the rear seats because of extra reinforcements (like what happened in the new ES).

As for the construction itself, all 3 cars (IS/RC/GS) are based on the same New N platform, so it's intended to share some components and to easily adapt between them as seen in the 2021 IS that have the same front casting from the older GS/RC.

If you ask me which one, I would have, it would be the IS because I’m in love by the design and the whole idea of the compact sports sedan that can be driven hard and take the whole family on vacations. But we can’t deny, right now, the RC F is superior on track, even Lexus says this IS 500 F Sport is not a full-F.

@Will1991 The IS 500 F SPORT is an improvement on the existing chassis. Explain lower spec transmission. It has the same AA80E transmission from the IS F/GS F and RC F.

The rear seats in the GS don't fold down either. It's a pretty dynamic chassis.

The RC mid section (rocker panel to firewall) is a modified version of the 2nd gen IS Convertible, old N platform. Hence it was designed to be a convertible that never happened. (see LF-CC).

RC F is superior on the track to what. References please.
 
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Faisal Sheikh

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I'm not misrepresenting facts. This is from my own driving experience on public roads and actual tracks. My research is not just from magazine articles and forum posts. As for chassis rigidity, There's a reason why the GS F doesn't have shock tower braces, the chassis was rigid to begin with (L10 GS Chassis).

There's no arguing the GS is larger than the RC F. The GS chassis in general is a better built chassis than the RC because it was designed entirely from the ground up, not a mix of other chassis. I had a 2015 GS 350 F SPORT...and loved it. I think it's more fun and engaging to drive than my RC F. Now if the GS F had a Torsen LSD option, it would have been the obvious choice. Since the IS 500 F SPORT Performance has it...it definitely has my interest.

I don't really care about skidpad testing or magazine reviews, I don't base my decisions on magazine racing. Ultimately it's what I want to buy...and how the car makes me feel. Great the RC F has 1g of lateral grip...how does that improve your drive to work or the grocery store? The modifications of the 2021 IS chassis are tremendous. Lexus is about continuous improvement and the new Lexus Driving Signature proves that. I've driven the LFA on the streets and the track...how about you?

I completely disagree. The GSF chassis is much less rigid than the RCF. Longer cars are much harder to reach the same level of torsional stiffness that could be achieved with shorter platforms. It is simply physics. That is why it feels harsher on bumpy roads. The reason is because they targeted a high much stiffness on the RCF. That is Yaguchi's own words. I could feel the flex in the GSF while the RCF is solid as a rock even almost going tripod on steep approach angles. There is a reason why RCF has faster lap times than the GSF on most tracks. There is a reason why Lexus never put an LSD on the GSF because it was not suitable for the car and you continue to ignore it. You cannot have it both ways.

Yes, the RCF is less comfortable, but it is due to higher stiffness. I was aiming for more sportiness and I found it in the RCF.
 

flipside909

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I completely disagree. The GSF chassis is much less rigid than the RCF. The reason is because they targeted a high much stiffness on the RCF. That is Yaguchi's own words. I could feel the flex in the GSF while the RCF is solid as a rock even when going tripod. There is a reason why RCF has faster lap times than the GSF on most tracks. There is a reason why Lexus never put an LSD on the GSF and you continue to ignore it. You cannot have it both ways.

Yes, the RCF is less comfortable, but it is due to higher stiffness. I was aiming for more sportiness and I found it in the RCF.

You could feel flex in the GS while the RC F is rock solid. How did you experience that?

Lighter and smaller, but only 0.1 second faster...okay sure. GS performs well in GS 350 format with or without the Torsen LSD. The GS F's price point would have been better if it didn't have a standard TVD. It still would have performed well without a TVD in my opinion.

2016 GS F
Lap time: 3:05.9

2015 RC F
Lap Time: 3:05.8
 
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Faisal Sheikh

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Different drivers and different conditions etc. I said MAJORITY for a reason. No arguments RCF had a severely bad showing in the C&D lightning lap and it has been discussed a lot and I don't want to start posting other numbers here. This is the only track where RCF rans slower than the ISF. That speaks volume.

Easily torsional flex can be tested at a steep approach angle cranking the steering tightly where almost your inner rear wheel lifts up in case of very high torsional rigidity. A chassis with some flex will tend to feel the inner rear wheel dropping down at the steepest angle. I have the more rigid CF roof, but I cannot see it being much different for other types. Back in the day, I read in one of the articles RCF is 50% stiffer than the standard GS platform.

This is pro race car driver Christian Menzel who drove both cars in the same conditions, same driver, same track. If you understand German, you can hear his opinions on it. There is AutoBild as well where RCF TVD lapped faster by a couple of seconds around Saschsenring.

Even Motor Trend drover them both back to back on the race track and said the RCF has higher limits and wants to be pushed harder while the GSF is more stable and more easy to approach the limits. Even Yaguch himself said, RCF is for people who prefer more ability to take it to the track while GSF for people who would prefer more practicality.

TFL Leader Board:

RCF (Carbon/TVD): 1:04
GSF: 1:07

Hockenheimring Short

RCF: 1:14
GSF: 1:15

Mendig AFB (AMS Fast Lap):

RCF carbon/TVD lap time: 1:56
GSF lap time: 1:59






Using the same 467-hp, 5.0-liter V-8 engine, the RC F powered aggressively through corners on the Chuckwalla Valley Raceway. With its smaller dimensions, the drive was more aggressive, enabling the driver to push the limits even further than the GS F. Because the GS F is larger and heavier, even if it's only by roughly 80 pounds, it didn't offer as sporty of a drive as the RC F. When it comes to driving on the track, hands down, the RC F is the way to go.

These guys also drove both RCF and GSF on the track

 
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flipside909

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Easily torsional flex can be tested at a steep approach angle turn cranking the steering tightly where almost your inner rear wheel lifts up in case of very high torsional rigidity. A chassis with some flex will tend feel the inner rear wheel dropping down at the steepest angle.

Faisal, it's okay buddy, at the end of the day, whatever makes you happy. I've been fortunate to meet Yaguchi-san in person in his travels to the United States for IS F and RC F. He's a huge part of Lexus performance history but don't necessarily agree with everything he's said. He is now retired from TMC.

IS 500 F SPORT Performance will be a great addition to the Lexus performance line up. I have high hopes it will perform as good if not better than the RC F. I like my 2020 RC F but I don't love it. Looking forward to trading it in for the IS 500 F SPORT Performance.
 
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Faisal Sheikh

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Faisal, it's okay buddy, at the end of the day, whatever makes you happy.

IS 500 F SPORT Performance will be a great addition to the Lexus performance line up. I have high hopes it will do better than the RC F. I like my 2020 RC F but I don't love it.

Thanks. Agreed.
 
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Ian Schmidt

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Right. Engine swaps *into* Lexus vehicles are much more rare and involved than the more common case of pulling 2JZs out of older GSes and dropping them into whatever, but they do happen.
 
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God, how beautiful this car is. It's just perfect. I want to buy it already. I'll definitely take it out on credit. I've been driving the Lexus ES for a year now. I want to give it up because I don't like the smooth ride and the looks. Also took it on credit at https://www.car.co.uk/car-finance. I got it on 'personal contract plans' or PCP car finance. I make a smaller payment every month because I am not paying the full price of the car. After 3 months I have to choose either to pay the remaining amount or give up the car. I will give it up and get a new one.
 
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Faisal Sheikh

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The IS500's Japanese direct rival embargo was lifted today. It will be available for $53,000 fully optioned. That is similar to a loaded IS350 F-Sport pricing. The IS500 would be at least a few grand more than that, but has a few things going for it. It has almost 120 HP more from an N/A V8 and at 4250 lbs, the TLX Type S is around 350 lbs heavier than the IS500.
 
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flipside909

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The IS500's Japanese direct rival embargo was lifted today. It will be available for $53,000 fully optioned. That is similar to a loaded IS350 F-Sport pricing. The IS500 would be at least a few grand more than that, but has a few things going for it. It has almost 120 HP more from an N/A V8 and at 4250 lbs, the TLX Type S is around 350 lbs heavier than the IS500.

IS 350 F SPORT Dynamic Handling Package > TLX Type-S at this point.

Also there's no dash in F SPORT. ;)
 
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