RC F (2015-present) Discussion topics related to the RC F model

Yaguchi Hints at "Continual Evolution" for RC F

Thread Tools
 
Search this Thread
 
Old 09-02-14, 04:50 AM
  #16  
DOC4LEX
Pole Position
 
DOC4LEX's Avatar
 
Join Date: Nov 2007
Location: KZN,South Africa
Posts: 274
Likes: 0
Received 0 Likes on 0 Posts
Default

I like what is said on this thread so the RCF could follow the same route as the GTR continuos development , i take my hat off for Mr Yaguchi Foresight.
Old 09-02-14, 04:51 AM
  #17  
spwolf
Lexus Champion
 
spwolf's Avatar
 
Join Date: Jan 2005
Posts: 19,841
Received 110 Likes on 81 Posts
Default

Originally Posted by 4TehNguyen
only major changes I can see are engine power, maybe a DCT, suspension revision, or ECU tune. RCF is starting out way ahead of what the ISF had when it was released. I dont really see as drastic changes as the ISF got during its lifetime. We know theres a lot more hidden potential in the engine because SARD was able to do a 30-40 hp upgrade just from an ECY tune and it isnt even that aggressive of a tune.
I dont see major changes in HP at all... Enhancements could be in suspension, steering feel, features etc, etc.

I expect much smaller changes than IS-F overall, as you said, because RC-F is already building up on last IS-F.
Old 09-02-14, 05:44 AM
  #18  
4TehNguyen
Lexus Fanatic
iTrader: (1)
 
4TehNguyen's Avatar
 
Join Date: Jan 2006
Location: Houston, Texas
Posts: 26,033
Received 51 Likes on 46 Posts
Default

dry sump system in RCF would be nice. Dry sump in the vette lets them lower the engine by a few inches which gives the bodywork a lower profile in addition to lower center of gravity. Stupid pedestrian safety standards is why the hood is bulged on the ISF/RCF. I can see dry sump being another potential upgrade.
Old 09-02-14, 07:40 AM
  #19  
spwolf
Lexus Champion
 
spwolf's Avatar
 
Join Date: Jan 2005
Posts: 19,841
Received 110 Likes on 81 Posts
Default

Originally Posted by 4TehNguyen
dry sump system in RCF would be nice. Dry sump in the vette lets them lower the engine by a few inches which gives the bodywork a lower profile in addition to lower center of gravity. Stupid pedestrian safety standards is why the hood is bulged on the ISF/RCF. I can see dry sump being another potential upgrade.
bulge is not due to safety standards in Europe... European IS has pop-up hood standard and has no issues passing regulations with low front end... I am sure the RC would be the same.

Bulge is due to the engine size, plus it looks great and gives car some character and distinction from regular RC models. I really like it.

Looking at all of these RC-F pictures is destroying the look of regular RC for me... RC-F looks so much nicer and the seats are awesome!
Old 09-02-14, 09:33 PM
  #20  
TF109B
Lexus Champion
 
TF109B's Avatar
 
Join Date: Apr 2010
Location: Washington
Posts: 2,266
Received 2 Likes on 2 Posts
Default

The GT3 version of the RC-F uses nearly the same exact engine configuration. GT3 regulations mean you can't change much from the road car. Thats why the Z4 uses a V8 from other bmw cars.
Old 09-02-14, 09:50 PM
  #21  
TimboIS
Liquid Bra Champion
 
TimboIS's Avatar
 
Join Date: Aug 2005
Location: ƒ(x)
Posts: 2,831
Received 139 Likes on 96 Posts
Default

Originally Posted by spwolf
bulge is not due to safety standards in Europe... European IS has pop-up hood standard and has no issues passing regulations with low front end... I am sure the RC would be the same.

Bulge is due to the engine size, plus it looks great and gives car some character and distinction from regular RC models. I really like it.

Looking at all of these RC-F pictures is destroying the look of regular RC for me... RC-F looks so much nicer and the seats are awesome!
Hood bulge is a side effect of safety. Minimum of 20mm required from the underside of the hood to the highest part of the engine. Taller engine == taller hood. It is what it is. That's why mid/rear-engine cars look better

http://www.caranddriver.com/features/taking-the-hit-how-pedestrian-protection-regs-make-cars-fatter-feature
Old 09-02-14, 10:44 PM
  #22  
05RollaXRS
Lexus Test Driver
 
05RollaXRS's Avatar
 
Join Date: Oct 2005
Location: Calgary, AB
Posts: 9,767
Received 2,417 Likes on 1,741 Posts
Default

I am still the biggest fan of the classic athletic proportions - long hood, short decklid and short overhang. Nothing beats that.

Just wish the RC-F nose bulge was a bit less, but I guess there is a good reason for that especially with that V8 in it, I would not complain.

Last edited by 05RollaXRS; 09-02-14 at 10:50 PM.
Old 09-03-14, 01:10 PM
  #23  
Joe Z
Lexus Fanatic
iTrader: (10)
 
Joe Z's Avatar
 
Join Date: Nov 2004
Location: Under an IS F since 2008
Posts: 13,446
Received 1,058 Likes on 586 Posts
Exclamation

Originally Posted by 05RollaXRS
RC-F already revs up to 7300 rpm (rev limit at 7450 rpm).
I thought we cleared this up already..

The safe RPM rev was raised & set to 7,200 RPM on the RC F.. (raised by 500 rpm)

The Red Line & Rev Limiter will be 7,300 RPM on the updated 2UR-GSE

The IS F was 6,700 & 6,800 respectively..


~ Joe Z

Last edited by Joe Z; 09-03-14 at 01:14 PM.
Old 09-03-14, 01:30 PM
  #24  
05RollaXRS
Lexus Test Driver
 
05RollaXRS's Avatar
 
Join Date: Oct 2005
Location: Calgary, AB
Posts: 9,767
Received 2,417 Likes on 1,741 Posts
Default

Originally Posted by Joe Z
I thought we cleared this up already..

The safe RPM rev was raised & set to 7,200 RPM on the RC F.. (raised by 500 rpm)

The Red Line & Rev Limiter will be 7,300 RPM on the updated 2UR-GSE

The IS F was 6,700 & 6,800 respectively..


~ Joe Z
I am going by what Lexus revealed in the official RC-F press release. It was stated redline is at 7300 rpm

http://www.leftlanenews.com/lexus-rc-f.html


Whereas most rivals rely on - or will soon switch to - forced-induction powerplants, the RC F utilizes a naturally-aspirated 5.0-liter V8. Sharing only displacement and a cylinder block with the IS F's mill, the direct- and port-injected V8 features a 12.3:1 compression ratio, a 7,300-rpm redline and preliminary power figures of more than 450 horsepower and 383 lb-ft of torque. Impressively, the mill can switch to the efficient Atkinson cycle during cruising situations in order to reduce fuel consumption.

Read more: http://www.leftlanenews.com/lexus-rc...#ixzz3CHq4UjDU
Old 09-03-14, 01:40 PM
  #25  
lobuxracer
Tech Info Resource

iTrader: (2)
 
lobuxracer's Avatar
 
Join Date: Jul 2006
Location: Georgia
Posts: 22,203
Received 3,848 Likes on 2,333 Posts
Default

Originally Posted by 05RollaXRS
RC-F already revs up to 7300 rpm (rev limit at 7450 rpm).
How do you figure? If the rev limiter is set to 7300, who cares what "redline" is because guess what? YOU"LL NEVER SEE IT. So for all intents and purposes, if the rev limiter is at 7300, redline is also at 7300.

Besides, redline is arbitrary under all circumstances. Do you really think the 2JZs spinning over 10,000 rpm at the drag strip are representative of the engine's "redline?" No, they expect to rebuild them very frequently.

20 m/sec mean piston speed is considered a conservative number for an engine designed to last a very long time. The Integra Type R has one of the highest mean piston speeds of any production engine at 24+ m/sec. Those 3.4 stroker 2JZ drag engines are WAY higher. Why? Simply because they are run at the ragged edge of reliability when 7 seconds at WOT is enough to need a complete teardown and rebuild. Ever watch Top Fuel racing? Doesn't matter if they're rails or funny cars, those engines don't run more than one pass without a complete rebuild.

If Yaguchi wants to rev the engine to make more power, there are a whole lot of things to consider. Dry sump isn't one of them. Mean piston speed (actually full kinematic analysis of the piston and rod is required), valvetrain actuation and spring rates, bottom end harmonic vibration, block strength, and a complete reconsideration of material choices are on the plate. Arbitrarily raising the redline without changing any components only means a shorter interval until major engine service is required. Period.

Here's a quick and dirty spreadsheet for calculating mean piston speed in m/sec and ft/min along with volumetric measures. You can manipulate the red numbers to see the impact of changing basic engine measurements. This information can be used to estimate power output.
Attached Files

Last edited by DaveGS4; 09-04-14 at 06:20 AM.
Old 09-03-14, 01:45 PM
  #26  
Joe Z
Lexus Fanatic
iTrader: (10)
 
Joe Z's Avatar
 
Join Date: Nov 2004
Location: Under an IS F since 2008
Posts: 13,446
Received 1,058 Likes on 586 Posts
Lightbulb

Originally Posted by 05RollaXRS
I am going by what Lexus revealed in the official RC-F press release. It was stated redline is at 7300 rpm
Again no argument there..!!!!

Shifts at 7,200 .. bounces at 7,300 RPM - REDLINE

There really is no other way to word it.

~ Joe Z

Attached Thumbnails Yaguchi Hints at "Continual Evolution" for RC F-2015-lexus-rc-f-dash-guages.jpg  
Old 09-03-14, 01:45 PM
  #27  
lobuxracer
Tech Info Resource

iTrader: (2)
 
lobuxracer's Avatar
 
Join Date: Jul 2006
Location: Georgia
Posts: 22,203
Received 3,848 Likes on 2,333 Posts
Default

Originally Posted by spwolf
I dont see major changes in HP at all... Enhancements could be in suspension, steering feel, features etc, etc.

I expect much smaller changes than IS-F overall, as you said, because RC-F is already building up on last IS-F.
QFT. I"ve been buying Toyota products for more than 25 years and Japanese engines for more than 35 years. Toyota never adds power to an existing platform. The IS-F didn't see any increase. The IS350 in its first iteration never saw another pony. They don't do the American thing or the German thing. They build a powerplant, certify it, and leave it alone. Been that way for so long it's not even funny.
Old 09-03-14, 01:47 PM
  #28  
TimboIS
Liquid Bra Champion
 
TimboIS's Avatar
 
Join Date: Aug 2005
Location: ƒ(x)
Posts: 2,831
Received 139 Likes on 96 Posts
Default

Can this thread be closed or moved to a "future" section? All this is just noise, detracting from the real event/news/vehicle.
Old 09-03-14, 03:18 PM
  #29  
spwolf
Lexus Champion
 
spwolf's Avatar
 
Join Date: Jan 2005
Posts: 19,841
Received 110 Likes on 81 Posts
Default

Originally Posted by TimboIS
Hood bulge is a side effect of safety. Minimum of 20mm required from the underside of the hood to the highest part of the engine. Taller engine == taller hood. It is what it is. That's why mid/rear-engine cars look better

http://www.caranddriver.com/features...fatter-feature
I am not so sure - IS and RC have special feature here.... IS and (probably) RC have pop-up hood... this is allowed by EuroNCAP and what happens is that when it detects the crash, hood pops up and creates bigger barrier between itself and the engine.

The new IS features an impact-absorbing pop up hood. Activated by sensors mounted in the front bumper, should you collide with a pedestrian, the system slightly raises the level of the bonnet to give more space between it and the hard components of the engine underneath. This reduces the risk of head injuries to the pedestrian.
Old 09-03-14, 04:02 PM
  #30  
05RollaXRS
Lexus Test Driver
 
05RollaXRS's Avatar
 
Join Date: Oct 2005
Location: Calgary, AB
Posts: 9,767
Received 2,417 Likes on 1,741 Posts
Default

I am going under the assumption that majority of the cars have rev limiters placed higher than their redlines.

Here are a few examples of many I could list:

BMW E92/E90 M3 S54: redline: 8400 rpm rev limiter: 8500 rpm
Lexus LFA 1LR: redline: 9000 rpm rev limiter: 9500 rpm
2ZZ-GE: redline: 8250 rpm rev limiter: 8350 rpm (8500 rpm for Lotus Elise)
K20: redline: 8000 rpm rev limiter: 8200 rpm
Audi R8 V10: redline: 8500 rpm rev limter: 8700 rpm
Audi R8 4.2: redline: 8000 rpm rev limiter: 8200 rpm

etc.

So if the RC-F has a redline of 7300 rpm as claimed by Lexus and shown in pictures above by JoeZ, there might be a chance that the rev limiter is about 100 rpm higher than the redliner. Again, there is a possibility that the rev limiter is right at 7300 rpm, but I am considering the other possibility as well. That is all I am saying.


Originally Posted by lobuxracer
How do you figure? If the rev limiter is set to 7300, who cares what "redline" is because guess what? YOU"LL NEVER SEE IT. So for all intents and purposes, if the rev limiter is at 7300, redline is also at 7300.

Besides, redline is arbitrary under all circumstances. Do you really think the 2JZs spinning over 10,000 rpm at the drag strip are representative of the engine's "redline?" No, they expect to rebuild them very frequently.

20 m/sec mean piston speed is considered a conservative number for an engine designed to last a very long time. The Integra Type R has one of the highest mean piston speeds of any production engine at 24+ m/sec. Those 3.4 stroker 2JZ drag engines are WAY higher. Why? Simply because they are run at the ragged edge of reliability when 7 seconds at WOT is enough to need a complete teardown and rebuild. Ever watch Top Fuel racing? Doesn't matter if they're rails or funny cars, those engines don't run more than one pass without a complete rebuild.

If Yaguchi wants to rev the engine to make more power, there are a whole lot of things to consider. Dry sump isn't one of them. Mean piston speed (actually full kinematic analysis of the piston and rod is required), valvetrain actuation and spring rates, bottom end harmonic vibration, block strength, and a complete reconsideration of material choices are on the plate. Arbitrarily raising the redline without changing any components only means a shorter interval until major engine service is required. Period.

Here's a quick and dirty spreadsheet for calculating mean piston speed in m/sec and ft/min along with volumetric measures. You can manipulate the red numbers to see the impact of changing basic engine measurements. This information can be used to estimate power output.

Last edited by DaveGS4; 09-04-14 at 06:20 AM.


Quick Reply: Yaguchi Hints at "Continual Evolution" for RC F



All times are GMT -7. The time now is 04:56 AM.