Next-Generation Lexus IS Sedan to be Offered with BMW Inline-Six Turbo Engine?

ssun30

Nice analysis here. A recurring theme with TNGA Lexus is a reduction of space efficiency in exchange for styling and driving dynamics. Making the LS500 with FMR layout is a wonderful decision and they should do that for the IS as well. It seems that enlarging the IS to Mark X size will add little to no cabin space.

Yep, but keep in mind that with ES they specifically added rear legroom :). Engine looks like it is positioned to take least possible amount of wheelbase.

If car makers made V4 engines, cars would have longer useful wheel base, short front overhang, better dynamics thanks to RWD or better AWD systems than transverse, and more refined engine than I4 or V6, and better layout hybridization without space loss. But with ICE on their deathbed (or not?), because of BEVs, it is probably to late to change.

Levi

If car makers made V4 engines, cars would have longer useful wheel base, short front overhang, better dynamics thanks to RWD or better AWD systems than transverse, and more refined engine than I4 or V6, and better layout hybridization without space loss. But with ICE on their deathbed (or not?), because of BEVs, it is probably to late to change.

The cost of quad cams on a V4 engine kills it. Same for B4. Subaru and Porsche only do B4 for legacy reasons.

Also with the ES growing HUGE in length, 196 inches, I fully expect the next IS to grow significantly as well.

There has to be a next IS F.

And bring a wagon too or a 5 door. lol

With conservative Lexus, I could see the TTV6 being the IS-F engine.

Yes bring back the IS Sportcross wagon (entry level) and bring on LS Sportcross wagon (LF-1 (flagship)).

Well, to reply to this thread, if the next IS will remain RWD based, new generation GS or not, if the IS does grow in size closer, I really want it to have more rear seat space mostly. If not, the current IS 300h does not lack anything at all.

ssun30

The cost of quad cams on a V4 engine kills it. Same for B4. Subaru and Porsche only do B4 for legacy reasons.

This then also applies to V6 vs I6. After BMW remaining committed to I6, Mercedes is replacing their V6 lineup by I6. JLR is also to follow suite, and so for Aston Martin (Mercedes engine). All other car makers have abandoned NA V6 for FI I4, Toyota is the only to use NA V6 (with Honda). Toyota needed BMW to put an I6 into their new Supra.

mordecai

With conservative Lexus, I could see the TTV6 being the IS-F engine.

This is, precisely, what I'm expecting. It could be tuned for more power than LS 500, though, since IS would surely be lighter than LS. As I've said time and again, Lexus makes its cars as powerful as possible without incurring a U.S. EPA Gas Guzzler penalty (LFA excepted).

mikeavelli

Also with the ES growing HUGE in length, 196 inches, I fully expect the next IS to grow significantly as well.

There has to be a next IS F.

And bring a wagon too or a 5 door. lol

I dont think it will grow a lot, a bit maybe. But it will be more sport focused for sure which again means tighter rear space.

I do expect IS500. Competition is doing it, they will too.

mikeavelli

Also with the ES growing HUGE in length, 196 inches, I fully expect the next IS to grow significantly as well.

There has to be a next IS F.

And bring a wagon too or a 5 door. lol

I hope it doesn't grow too much. I am considering it for my next car, but I live in a city and appreciate a compact size. I hope it doesn't grow more than a couple inches in overall length.

GS4 has a 5cm longer wheelbase than IS3, yet is almost 20cm longer overall. It means the remaining 15cm happen at the overhangs. Overhangs are what make a car huge and difficult to drive in tight spaces, because it is harder to estimate the overhangs, that to feel the wheelbase. If the new IS gets a slightly longer wheelbase, where all to added space goes to rear seats, but overhangs remain short, it would remain a 'compact' sporty sedan, with rear seats good for long trips.

Levi

GS4 has a 5cm longer wheelbase than IS3, yet is almost 20cm longer overall. It means the remaining 15cm happen at the overhangs. Overhangs are what make a car huge and difficult to drive in tight spaces, because it is harder to estimate the overhangs, that to feel the wheelbase. If the new IS gets a slightly longer wheelbase, where all to added space goes to rear seats, but overhangs remain short, it would remain a 'compact' sporty sedan, with rear seats good for long trips.

This is why the LWB 3-series gets much more rear space than SWB 5-series despite being much shorter; in fact the sub-4.8m 3-Series L has more legroom than full-size SUVs like the GLS or Range Rover. It's ridiculously space efficient.
However, for the IS a lot of wheelbase stretch will be used to allow a FMR layout (if they keep doing it for the IS). I'm expecting at most 50mm/2in longer interior cabin to make the rear usable but definitley not spacious. But usable is all they need.
To me a 4GS with 50mm shorter overhangs and front axle moving forward by 20mm is a perfect size for 4IS. The side profile of the 4GS looks very compact for its actual size. I don't think maneuvrability is a concern for sedan shoppers since they are already sacrificing maneuvrability by choosing a sedan in the first place. The only place where a 4800mm IS could have major difficulty moving is Japan, but the compact-size 3IS is a whale on Japanese roads already.

ssun30

This is why the LWB 3-series gets much more rear space than SWB 5-series despite being much shorter; in fact the sub-4.8m 3-Series L has more legroom than full-size SUVs like the GLS or Range Rover. It's ridiculously space efficient.
However, for the IS a lot of wheelbase stretch will be used to allow a FMR layout (if they keep doing it for the IS). I'm expecting at most 50mm/2in longer interior cabin to make the rear usable but definitley not spacious. But usable is all they need.
To me a 4GS with 50mm shorter overhangs and front axle moving forward by 20mm is a perfect size for 4IS. The side profile of the 4GS looks very compact for its actual size. I don't think maneuvrability is a concern for sedan shoppers since they are already sacrificing maneuvrability by choosing a sedan in the first place. The only place where a 4800mm IS could have major difficulty moving is Japan, but the compact-size 3IS is a whale on Japanese roads already.

They are not going to make IS 4.8m... doesnt make much sense. They will make it similar size with larger wheelbase, like many of TNGA vehicles.

The Infiniti Q50 is in the same class as IS, it is compared to A4, C Class and 3 Series. Yet is has the same wheelbase of 2.8m and an overall length of4.81m (4cm shorter than GS4). While the Q50 has no low powered hybrid, it has a high powered hybrid version, equivalent to GS 450h, hypothetical IS 450h, that I see being replaced by the 500h used in LS and LC. New IS should have a more powerful hybrid. Just as you can choose from different power ICE, so you should be able to chose from different poyer HEV and BEV.

Levi

The Infiniti Q50 is in the same class as IS, it is compared to A4, C Class and 3 Series. Yet is has the same wheelbase of 2.8m and an overall length of4.81m (4cm shorter than GS4). While the Q50 has no low powered hybrid, it has a high powered hybrid version, equivalent to GS 450h, hypothetical IS 450h, that I see being replaced by the 500h used in LS and LC. New IS should have a more powerful hybrid. Just as you can choose from different power ICE, so you should be able to chose from different poyer HEV and BEV.

sure, but Lexus will not have 3 large sedans... IS needs to be small sporty sedan, or else whats the point?

Q50 is not a great vehicle, it should not be what Lexus IS targets.

spwolf

or else whats the point?

Hint: 7ES is huge. It's not mid-size; it's full-size.

4800mm was the upper bound I assumed for the 4IS, of course they can build it smaller, but anything smaller than the Mark X would be a problem.

spwolf

sure, but Lexus will not have 3 large sedans... IS needs to be small sporty sedan, or else whats the point?

Q50 is not a great vehicle, it should not be what Lexus IS targets.

Amen!

Lexus GS3 and GS4 wheelbase remained the same at 2850 mm. The IS3 wheelbase grew by 70 mm to 2800 mm from the IS2 wheelbase of 2730 mm.

Lexus IS is the smallest in this class, and as Lexus does not have any compact FWD sedan (Toyota takes care of that space), and the ES takes care of the entry (real) luxury space, the IS will likely remain in the compact sport space.

Japanese publication Mag X has a rough sketch of the 4IS:



https://www.mag-x.com/shop/products/detail.php?product_id=109

It looks as though styling will be fairly evolutionary. Also something is mentioned about an "expansion" of the IS body along with demand of GS disappearing. I can only assume this means the 4IS will get bigger, but I don't speak Japanese so cannot confirm. It matches some rumors though that the GS may disappear, and the IS may grow physically/get an expanded lineup. A new 2.4L turbo engine is also mentioned for the IS.

Maybe the IS might be the first to get the 2.4L TT in the TS050 (who knows...)

bogglo

Maybe the IS might be the first to get the 2.4L TT in the TS050 (who knows...)

The 2.4L turbo will be Inline-4 not a 90-degree V6.

ssun30

The 2.4L turbo will be Inline-4 not a 90-degree V6.

If I remember correctly, a number of engines in the past (Audi comes to mind) have reduced their displacement via thicker cylinder walls/linings when boosting their engines. Could this rumored 2.4-liter turbo be nothing more than a turbocharged version of the latest Camry's 2.5-liter A25A-FKS 4-cylinder engine? Under this theory, thicker cylinder walls/linings would reduce cylinder displacement slightly to create an A24A-FTS engine.

http://performancedrive.com.au/2020-lexus-is-to-be-topped-by-twin-turbo-v6-flagship-rumour-0409/

Rumors the LS TT-V6 makes it in the new IS. It better Lexus lags way behind now in hp in this segment.

mikeavelli

http://performancedrive.com.au/2020-lexus-is-to-be-topped-by-twin-turbo-v6-flagship-rumour-0409/

Rumors the LS TT-V6 makes it in the new IS. It better Lexus lags way behind now in hp in this segment.

On the plus side, that's something I've wanted to see for months. On the minus side, rumors out of Australia tend to be a little sketchy.

Joaquin Ruhi

If I remember correctly, a number of engines in the past (Audi comes to mind) have reduced their displacement via thicker cylinder walls/linings when boosting their engines. Could this rumored 2.4-liter turbo be nothing more than a turbocharged version of the latest Camry's 2.5-liter A25A-FKS 4-cylinder engine? Under this theory, thicker cylinder walls/linings would reduce cylinder displacement slightly to create an A24A-FTS engine.

This is the first time I hear of this and I don't know if such practice is widely used or not. Past Toyota turbocharged engines always have the exact same dimensions as NA counterparts. We don't even know if the 2.4 number is true.

CIF

Japanese publication Mag X has a rough sketch of the 4IS:



https://www.mag-x.com/shop/products/detail.php?product_id=109

No matter how hard I tried, I could not purchase this magazine online. I have an account, but password won't work. Have requested a reset, fingers crossed!

Actually found it on the Amazon.jp website, here's the IS article:

View attachment 2911

Anyone want to translate the important parts?

If that indeed is what the next IS will look like, it marks the great homogenization of Lexus.

It’s not necessarily a bad thing so long as the theme and underlying design element (that is being duplicated) is good.

Mercedes, Audi, BMW are all doing it, but the drawback is if the underlying theme sucks, well, the entire lineup follows suit. It’s all or nothing. Conversely, if it’s good, the exact opposite is true. Regardless, it creates a familiar identity; BMW has used this to a fault, good or bad.

Awesome find krew! The rear end of the sketch is really rough, so they don't know exactly yet what it will look like.

I can't translate the thing, but tidbits I was able to discern:

- Talking about the LC and TNGA, the 4IS is obviously using GA-L.
- LC F and IS F are mentioned as well as the rumored 4.0L TT V8. Sounds like that means we could get a next-gen IS F with the rumored TT V8
- The UX is also oddly mentioned
- Both the 2.4L 4 cylinder turbo as well as the A25A engine are both mentioned. Different engines for different markets, or a sign that the 2.4L 4 cylinder turbo is related to the A25A?

- Listed dimensions for 4IS:
Wheelbase 2870mm (113 inch) ?
Length 4730mm (186.2 inch)
Width 1815mm (71.5 inch)
Height 1425mm height (56.1 inch)

For comparison, current 3IS dimensions:
Wheelbase 2,800 mm (110.2 in)
Length 4,681 mm (184.3 in)
Width 1,810 mm (71.3 in)
Height 1,430 mm (56.3 in)

Current 4GS dimensions:
Wheelbase 2,850 mm (112.2 in)
Length 4,879 mm (192.1 in)
Width 1,840 mm (72.4 in)
Height 1,455 mm (57.3 in)

LC dimensions:
Wheelbase 2,870 mm (113.0 in)
Length 4,760 mm (187.4 in)
Width 1,920 mm (75.6 in)
Height 1,345 mm (53.0 in)

There is a question mark though about the wheelbase as I can't read Japanese, and can't confirm if the wheelbase is indeed matching that of the LC. If true though, that's a noticeable length and significant wheelbase increase for the 4IS. That's also an identical wheelbase to the LC and extremely similar length. The IS getting LC dynamics...that would be huge. Also signifies decreased overhangs for the 4IS. Bigger wheelbase than the 4GS as well. So according to the measurements, size-wise the 4IS won't totally match the GS, but it gets closer to GS size than before. Of course, if we do get a next-gen GS in the future, it will be sure to grow in size.

A25A-FKS = naturally aspirated
A25A-FXS = naturally aspirated + electric motor (hybrid)
A25A-FTS = forced induction (turbo)

?