2016's
07-31-15, 06:48 AM
#92
Whew, I'm glad you debunked the points I was referencing. Good to know the ECU's aren't encrypted. I'll be sure and get that over to dozens of tuners right away. Also, it's refreshing how you explained that engines with essentially the same displacement in the Lexus lineup can vary so widely in output. /s
Next time bring some facts. Here are some examples.
2015 Lexus RC 350: curb weight 3,748lbs. Engine: 306hp 3.5l 60 degree V6. 0-60, 5.8s
2015 Lexus IS 350 RWD: curb weight 3,593lbs. Engine: same as above. 0-60, 5.6s
2015 Lexus GS 350 RWD: curb weight 3,726lbs. Engine: same. 0-60, 5.5-5.6s
So obviously, the RC is doing something wrong here. It is literally 22lbs heavier with .2s slower 0-60. Is the aero worse? A little. But weight isn't a big deal, that's like a bag of dog food heavier than the GS.
These numbers came straight from Lexus' website, I didn't pull them out of thin air, MINUS the GS numbers which Lexus didn't bother to publish. Motortrend and other magazines have reported anywhere from 5.4 to 5.7 depending on conditions, so I threw in the median average.
BRB putting my tinfoil hat back on.
Next time bring some facts. Here are some examples.
2015 Lexus RC 350: curb weight 3,748lbs. Engine: 306hp 3.5l 60 degree V6. 0-60, 5.8s
2015 Lexus IS 350 RWD: curb weight 3,593lbs. Engine: same as above. 0-60, 5.6s
2015 Lexus GS 350 RWD: curb weight 3,726lbs. Engine: same. 0-60, 5.5-5.6s
So obviously, the RC is doing something wrong here. It is literally 22lbs heavier with .2s slower 0-60. Is the aero worse? A little. But weight isn't a big deal, that's like a bag of dog food heavier than the GS.
These numbers came straight from Lexus' website, I didn't pull them out of thin air, MINUS the GS numbers which Lexus didn't bother to publish. Motortrend and other magazines have reported anywhere from 5.4 to 5.7 depending on conditions, so I threw in the median average.
BRB putting my tinfoil hat back on.
. Back in the day the only way to tune an ecu is to install an EPROM chip. That was in the 90's. Now they are too complicated.The engines in all 3 vehicles, are EXACTLY the same. Any power differences are based on different intake/exhaust designs. Otherwise, they are the same car.
As for the weight,
RC 350 3,748 lbs.
RC 350 AWD 3,891 lbs.
GS350 3,795 lbs.
AWD: 3,980 lbs.
OK, the GS is a small child heavier, you got me.
http://pressroom.lexus.com/releases/...specs.download
http://pressroom.lexus.com/releases/...specs.download
When you compare these, it is interesting to note the rear diff ratio on the RC is lower (higher numerical value) but the AWD is the same. This should give the RC a slight 0-60 advantage - however, it may make the RC shift slightly before 60mph, where the GS shifts slightly after 60mph, which would explain the .2s slower 0-60 time
.
The reverse ratio is different, but it appears to be an error on the GS, as 2:1 is too low.
The C&D Results, RC350:
http://www.caranddriver.com/lexus/rc
C/D TEST RESULTS:
Zero to 60 mph: 5.7 sec
Zero to 100 mph: 13.7 sec
Zero to 130 mph: 25.4 sec
Rolling start, 5-60 mph: 6.3 sec
Top gear, 30-50 mph: 3.1 sec
Top gear, 50-70 mph: 4.0 sec
Standing ¼-mile: 14.2 sec @ 102 mph
Top speed (governor limited): 146 mph
Braking, 70-0 mph: 174 ft
Roadholding, 300-ft-dia skidpad: 0.88 g
And 2013 GS350's (with the 6 speed, not the 8 speed)
C/D TEST RESULTS (AWD):
Zero to 60 mph: 5.6 sec
Zero to 100 mph: 14.5 sec
Street start, 5-60 mph: 6.2 sec
Top gear, 30-50 mph: 3.2 sec
Top gear, 50-70 mph: 3.7 sec
Standing ¼-mile: 14.3 sec @ 99 mph
Top speed (governor limited): 131 mph
Braking, 70-0 mph: 165 ft
Roadholding, 200-ft-dia skidpad: 0.87 g
C/D TEST RESULTS (F SPORT):
Zero to 60 mph: 5.5 sec
Zero to 100 mph: 13.7 sec
Street start, 5-60 mph: 5.8 sec
Top gear, 30-50 mph: 3.2 sec
Top gear, 50-70 mph: 3.4 sec
Standing ¼-mile: 14.1 sec @ 102 mph
Top speed (governor limited): 142 mph
Braking, 70-0 mph: 160 ft
Roadholding, 200-ft-dia skidpad: 0.89 g
The Trap speed is exactly the same for both vehicles, which is a good indicator of similar power. What is worrying, is that the GS stops 10-15' quicker.
Last edited by GregCanada; 07-31-15 at 07:02 AM.
07-31-15, 08:23 AM
#93
Lexus Test Driver
So the GS is a better car overall. I'm liking that 5.5 sec time. 
07-31-15, 11:18 AM
#94
Lexus Test Driver
http://www.lexus.com/models/GS/specifications
GS 350 RWD = 3,726lb. I was comparing RWD to RWD to prevent skewing the numbers. But your PDF shows the 2014 weighing 3,795lb for the same car, we can only assume. Regardless of which number is correct (probably both depending on options) the RC is still nearly the exact same weight minus a bag of dog food and .2s slower to 60 on average.
I know my wackadoodle theory about keeping cheaper models slower on paper despite having identical drivetrains in almost identical weight vehicles sounds crazy, but consider this. The Porsche Cayman is very close to the 911 in performance, particularly when you get into the S and R spec vehicles. However, it is much, much cheaper. As a potential 911 owner, it's unimaginable that a Cayman would be able to outrun you, because naturally, you paid a lot more. It's not out of the realm of possibility that manufacturers recycling drivetrains in different models will tweak them to add or subtract performance, based on which price bracket they belong to, for this reason alone.
Shift points, small variations in intake and valve design, etc. are all practically free engineering solutions to what is a consumer-led problem.
Basically, my point is that, to me, it's no secret that manufacturers will tune or detune engines based on the model's tier and target price range. Same hp, same torque, same powerband, different 0-60 results with similar weight, to keep buyers happy that their car is fractionally faster than the cheaper model.
And thanks for bringing some good data in, GregCanada.
GS 350 RWD = 3,726lb. I was comparing RWD to RWD to prevent skewing the numbers. But your PDF shows the 2014 weighing 3,795lb for the same car, we can only assume. Regardless of which number is correct (probably both depending on options) the RC is still nearly the exact same weight minus a bag of dog food and .2s slower to 60 on average.
I know my wackadoodle theory about keeping cheaper models slower on paper despite having identical drivetrains in almost identical weight vehicles sounds crazy, but consider this. The Porsche Cayman is very close to the 911 in performance, particularly when you get into the S and R spec vehicles. However, it is much, much cheaper. As a potential 911 owner, it's unimaginable that a Cayman would be able to outrun you, because naturally, you paid a lot more. It's not out of the realm of possibility that manufacturers recycling drivetrains in different models will tweak them to add or subtract performance, based on which price bracket they belong to, for this reason alone.
Shift points, small variations in intake and valve design, etc. are all practically free engineering solutions to what is a consumer-led problem.
Basically, my point is that, to me, it's no secret that manufacturers will tune or detune engines based on the model's tier and target price range. Same hp, same torque, same powerband, different 0-60 results with similar weight, to keep buyers happy that their car is fractionally faster than the cheaper model.
And thanks for bringing some good data in, GregCanada.
07-31-15, 12:34 PM
#96
Lead Lap
I think it just means they're adding the F.....that being the "major" change to the GS line.
07-31-15, 12:48 PM
#97
http://www.lexus.com/models/GS/specifications
GS 350 RWD = 3,726lb. I was comparing RWD to RWD to prevent skewing the numbers. But your PDF shows the 2014 weighing 3,795lb for the same car, we can only assume. Regardless of which number is correct (probably both depending on options) the RC is still nearly the exact same weight minus a bag of dog food and .2s slower to 60 on average.
I know my wackadoodle theory about keeping cheaper models slower on paper despite having identical drivetrains in almost identical weight vehicles sounds crazy, but consider this. The Porsche Cayman is very close to the 911 in performance, particularly when you get into the S and R spec vehicles. However, it is much, much cheaper. As a potential 911 owner, it's unimaginable that a Cayman would be able to outrun you, because naturally, you paid a lot more. It's not out of the realm of possibility that manufacturers recycling drivetrains in different models will tweak them to add or subtract performance, based on which price bracket they belong to, for this reason alone.
Shift points, small variations in intake and valve design, etc. are all practically free engineering solutions to what is a consumer-led problem.
Basically, my point is that, to me, it's no secret that manufacturers will tune or detune engines based on the model's tier and target price range. Same hp, same torque, same powerband, different 0-60 results with similar weight, to keep buyers happy that their car is fractionally faster than the cheaper model.
And thanks for bringing some good data in, GregCanada.
GS 350 RWD = 3,726lb. I was comparing RWD to RWD to prevent skewing the numbers. But your PDF shows the 2014 weighing 3,795lb for the same car, we can only assume. Regardless of which number is correct (probably both depending on options) the RC is still nearly the exact same weight minus a bag of dog food and .2s slower to 60 on average.
I know my wackadoodle theory about keeping cheaper models slower on paper despite having identical drivetrains in almost identical weight vehicles sounds crazy, but consider this. The Porsche Cayman is very close to the 911 in performance, particularly when you get into the S and R spec vehicles. However, it is much, much cheaper. As a potential 911 owner, it's unimaginable that a Cayman would be able to outrun you, because naturally, you paid a lot more. It's not out of the realm of possibility that manufacturers recycling drivetrains in different models will tweak them to add or subtract performance, based on which price bracket they belong to, for this reason alone.
Shift points, small variations in intake and valve design, etc. are all practically free engineering solutions to what is a consumer-led problem.
Basically, my point is that, to me, it's no secret that manufacturers will tune or detune engines based on the model's tier and target price range. Same hp, same torque, same powerband, different 0-60 results with similar weight, to keep buyers happy that their car is fractionally faster than the cheaper model.
And thanks for bringing some good data in, GregCanada.
08-02-15, 03:52 PM
#98
Lexus Fanatic
08-03-15, 08:03 AM
#99
Thread
Thread Starter
Forum
Replies
Last Post
Mixman
GS - 4th Gen (2013-2020)
37
12-10-14 01:56 PM