Next Gen NSX

[naaman]

Has anyone else seen the supposed next generation NSX at caranddriver.com? The picture looks like a fake one: using the front of an S2000, and the side door of a ferrari, I think. Anyway, its supposed to have a V8 and make 395 horsepower. A racing version is supposed to also come out with it that makes 415 horsepower. It's also supposed to cost $143,000. http://www.caranddriver.com/xp/Caranddriver/features/2001/January/200101_feature_supercar_acura.xml

 

[hendu]

It says on sale in Spring 2002, so I guess they are talking about the facelift (that they didn't even get right). Sounds like someone at C&D is talking out their butt.

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1994 Red/Black NSX #418
Forums Nazi Groupie

 

[Ojas]

Originally posted by hendu:
...Sounds like someone at C&D is talking out their butt.

Well, the article was written over a year ago.

 

[Tom Larkins]

Typical of C & D filling up space on a page with BS..

 

[ivan11]

There are rumors that the next NSX is going to swicht to a steel struture!!!!I hope that rumor is not true and it stays with its aluminum unitbody.....Anybody knows about it?

 

[RyRy210]

All of this has been discussed before awhile back. Do a search to see the responses.

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NA1 NSX-T
- Comptech Headers
- NA2 Brake Upgrade
- Eibach Springs
- Bilstein Shocks
- Zanardi F&R Sway Bar
- '02 OEM Wheels

 

[Jimbo]

Just another rumor. No one except Honda knows for sure.

I don't necessarily have a problem with certain parts being steel if it means the car will be lighter.

Heck, why not titanium?

-Jim

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1992 NSX Red/Blk 5 spd #0330
1991 NSX Blk/Blk Auto #3070 (Sold)
1974 Vette 454 4 spd Wht/Blk
Looking for 76-79 Honda Accords

 

[ivan11]

Come on my friend wake up, steel is not lighter that aluminum....If this car changes to a steel structure or uses some parts in steel you can bet that is going to be heavier!!!!!!

[This message has been edited by ivan11 (edited 24 May 2002).]

 

[ivan11]

The next NSX has to use a State of the Art Aluminum Spaceframe like the Ferrari 360 or Audi A8 to stay competitive!!!!!Not only in weight but in rigidity also!!!!!

 

[Jimbo]

ivan11,

Come on my friend wake up!

Steel is not lighter than aluminum but it is much stronger than aluminum and therefore you can use less of it.

You can't always generalize by saying an aluminum structrure will always be lighter and more efficient than steel.

-Jim

PS: The C5 Corvette has a big (compared to the NSX) V8 engine and steel hydroformed backbone chassis and yet it weighs approximately the same as the NSX.

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1992 NSX Red/Blk 5 spd #0330
1991 NSX Blk/Blk Auto #3070 (Sold)
1974 Vette 454 4 spd Wht/Blk
Looking for 76-79 Honda Accords

 

[ivan11]

Well that is because the NSX chassis despite using aluminum is a dated structure(12 years old already) when you compare it to the Vette unitbody and the Corvette has a fiberglass body that is even lighter than the NSX aluminum body!!!...Not necessarily because a car uses steel means that it its stronger....Look at the Audi A8 it uses a aluminum spaceframe and it its stronger and more rigid than many steel cars in its category!!!!

Why is that because of the alloys the use and the Thickness of the aluminum...You can make an aluminum car stronger that a steel car by playing with the thickness of the alloy and at the same time lighter!!!

The ferrari 360 also uses a aluminum spaceframe and the car is much more rigid than the Steel unitbody of its predecessor the ferrari 355!!!

Think about that!!!!Jim!!!!!

[This message has been edited by ivan11 (edited 24 May 2002).]

 

[Jimbo]

Ivan11,

I would hope that if the NSX were redone in aluminum that it could be made lighter than the current design.

The Corvette C5 is about the same weight as the NSX, not because of the plastic body panels but because of clever design and the inherent lighter weight of the front engine - rear drive design. And because the steel structure is fairly light.

I would agree that just because a car has a steel structure doesn't make it necessarily stronger. But that wasn't the point. I think we both agree that good design and engineering are important regardless of the material choice.

There are high-strength aluminum alloys and there are also high-strength steel alloys as well.

You can cite examples like the Audi and Ferrari 360 and they're good examples...but...you can't always make a blanket statement that aluminum is always going to produce the lightest and strongest structure.

It could very well be that Honda engineers could find that the best choice for the next NSX is a high-strength steel structure with lightweight plastic outer body panels.

I have no special interest or affinity for aluminum. I don't own stock in Alcoa

and it has a fair number of drawbacks. You need to use specially coated fasteners and be very careful in the design to avoid contact with ferrous components. It's also expensive to repair and requires special expertise.

Don't get me wrong, I love my NSX and I appreciate Honda's efforts that they took 12 years ago to make it lightweight and strong.

However, I think one needs to have an open mind and be open to other alternatives.

If you really want to "blue sky" and speculate about this...

Structural titanium is just starting to become affordable. We've seen it being used in exhaust systems and all kinds of common structural applications. It's also very resistant to corrosion.

I'd like to see Honda, if they could do it affordably, go to a titanium structure with carbon fiber reinforced plastic body panels. There is also technology that is drammatically bringing down the cost of carbon FRP panels that is now available.

I would also like to see a design where Honda could still have a removable roof panel that wouldn't compromise the structural integrity. It makes such a difference to be able to tie in the windshield header with the B-pillar somehow. Perhaps a removable center panel or a center bar?

Or...Honda could use steel or aluminum as well. As I said, I don't particularly care as long as it's light and strong.

If Honda can move to a 400+ HP V8 engine while coming in a 2750-2900 pounds I think we would all be real happy.

Regards,
Jim

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1992 NSX Red/Blk 5 spd #0330
1991 NSX Blk/Blk Auto #3070 (Sold)
1974 Vette 454 4 spd Wht/Blk
Looking for 76-79 Honda Accords

 

[Tom Larkins]

Originally posted by Jimbo:
Ivan11,

If Honda can move to a 400+ HP V8 engine while coming in a 2750-2900 pounds I think we would all be real happy.

Regards,
Jim

No problem, just keep the asking price under a $100k....

 

[ivan11]

Yes Jim i agree you need also clever engineering in a car to bring the weight down regarless of the material...But right now there is an aluminum boom in the auto industry and i think it has arrive to stay!!!

Now that you mentioned the Vette there are rumors that even the next generation corvette C6 is going to change to an aluminum structure will see.....

By the way the Corvette C5 is good example of great engineering in America best sports car!!!!GM also trim down a lot of weight and bulk in the Vette by using a pushrod engine instead of a mutivalve engine wise move!!!!

Titanium would be great in the structure of the car but also it would be a challenge for engineers to design it so its weight approaches that of aluminun.......

Carbon Fiber would be also a great addition to the NSX!!! I think that the NSX engineers are not going to dissapoint us with the next generation!!!!!If they are going to use a V8 they have to trim down weight some place.....

[This message has been edited by ivan11 (edited 24 May 2002).]

[This message has been edited by ivan11 (edited 24 May 2002).]

 

[Jimbo]

ivan,

There is a lot of use and interest in aluminum today. All the rumors I've heard about the C6 involve maintaining a hydroformed steel chassis.

GM also has some really good ideas on engines too. Their new XV8 prototype is interesting.
http://www.wieck.com/public/*2PV_037891
http://www.wieck.com/public/*2PV_037894

It might be a great way to trim down the size and weight of a DOHC design.

Regarding titanium....I'm not sure I follow you when you said that it would be a challenge meet the weight of aluminum. Titanium has approximately the strength of steel but the weight of aluminum. For example, if the current aluminum structure of the NSX were made from Ti it would be the same weight but 2-3 times as strong. Obviously the real benefit would be to redesign the structure for Ti so that it would weigh even less than the current design.

The only challenge I see would be the cost.

-Jim

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1992 NSX Red/Blk 5 spd #0330
1991 NSX Blk/Blk Auto #3070 (Sold)
1974 Vette 454 4 spd Wht/Blk
Looking for 76-79 Honda Accords

 

[ivan11]

Well Jim Titanium comes pretty close to aluminun in weight but still aluminum has the edge here are some facts that i just found out..

Density of:
Steel 0.29 lbs./cu.in.
Titanium 0.16 lbs./cu.in.
Aluminum 0.12 lbs./cu.in

As you can see titanium falls in the middle of steel and aluminum in weight...Like the ham of a sandwich.....

 

[JoeSchmoe]

Alright... I cringe every time I hear titanium.

Although I agree that titanium is relatively strong and relatively light, I dont feel that it is the miracle material that everyone makes it out to be. Having machined and used the stuff, I still dont see the miracle in it at all.


Myth #1 - titanium is stronger than steel. While titanium (~140KPSI) is stronger than mild steels (~40KPSI ie, lawn chairs, exercise machines, paint cans, etc) it is actually weak when compared with higher grade steels such as 300M (~240KPSI - 300KPSI depending on application). 300M has twice the tensile strength as 6al4v (grade 5) titanium, but at much lower cost.

Myth #2 - titanium is harder than steel. While titanium is harder than some steels, tool steels easily go up to 60RC and cut titanium just fine. Even 300M (from previous example) can be easily hardened to 50-55RC and be used to cut titanium.


Titanium is difficult to weld. If you want to torch, arc, or MIG/TIG weld it... forget it. You will need to do it in a sealed chamber. The F14 uses a titanium box in the fuselage and Grumman (its maker) had to develop a new special electron beam welding process just to weld the thick sections required.

Like aluminum, titanium alloys are also notch sensitive. This means that even small scratches or nicks can lead to the part to failure after a number of stress cycles (ie, driving over bumps).

Titanium alloys are brittle. If you take a bar of 6al4v and you bend it too far, it will just snap into two pieces. If you crash a chassis made of the stuff, your car will explode like a ming vase. So much for crumple zones.

So why does everyone keep talking about titanium as if it were a miracle metal?

I have a feeling that its largely due to its extensive use in aircraft engines. One benefit of titanium is that it retains its strength relatively well when hot -- like in a flaming hot jet engine.

Titanium also is good in shear and has decent tensile so it makes good lightweight fasteners. The purer alloys (ie, weaker) used in fasteners also allow it to resist corrosion better.

On a slightly different note, the titanium corvette exhaust most likely uses pure titanium because it needs to be bent and rolled into the complex shapes. The stronger alloys that you would use for structural elements cannot be bent as such and probably need to be forged (expensive).


In conclusion, titanium is overly expensive to make and fabricate. Most of the time, you can get steel and aluminum to do the same job as titanium for a lot less money. The S2000 connecting rods for example are steel and hold up just fine despite being lightened extensively to run at 9000RPM.

So... I sincerely hope that honda uses titanium sparingly -- perhaps in the exhaust.

Personally, Im hoping they use a 4130 tube chassis paneled in with aluminum sheet with carbon fiber bodywork. A bonded and riveted aluminum tub chassis (like the elise) with CF bodywork would be nice too. I just hope they ditch the welded aluminum chassis design they are using now. Welded 5xxx and 6xxx series aluminum alloys just sucks.


Ugh... titanium.

 

[JoeSchmoe]

Originally posted by ivan11:

Density of:
Steel 0.29 lbs./cu.in.
Titanium 0.16 lbs./cu.in.
Aluminum 0.12 lbs./cu.in

As you can see titanium falls in the middle of steel and aluminum in weight...Like the ham of a sandwich.....

FYI - the density of the 5xxx and 6xxx aluminum alloys (also used in the NSX) are ~0.097 lb/in^3 and not 0.12... the lower crust on your sandwich just got thinner =)

 

[ivan11]

Well i think titanium it could be used in several areas of cars..I have heard that in cars suspension springs,camshafts, valve springs,rocker arms just to name a few we could see the use of Ti in the near future..And infiniti is using Ti in the q45 valves....Ti is being used more and more Boeing 777 uses Ti 10-2-3 in the landing gear...I don't think we will see it in structural parts of cars, but it can be used in different areas of cars..

What makes Ti attractive is its strenght and light weight....Is about 50%lighter that steel...And Ti is one of the few metals that is completly immune to different types of corrosion.

By the way the Ti6 is not the strongest of all Ti.Ti10 and the ones in the Beta family are the strongest Ti!!!!!

[This message has been edited by ivan11 (edited 25 May 2002).]

[This message has been edited by ivan11 (edited 25 May 2002).]

[This message has been edited by ivan11 (edited 25 May 2002).]

 

[Tony Montoya]

What is wrong exactly with welded aluminium?
Are the Supra guys right when they say the chassis will fail after a certain number of stresses?

 

[ivan11]

Originally posted by Tony Montoya:
What is wrong exactly with welded aluminium?
Are the Supra guys right when they say the chassis will fail after a certain number of stresses?

Tony i think that what he wants to say is that by todays standards, there are other techniques by which you can make a better aluminum structure.The NSX is a aging structure and i don't think that it even uses LASER welding...

As we can see Audi and Ferrari has taken the aluminum structure a step further with their respective spaceframes...They used less welding,more rivets and less parts.Because of that their unitbodys are stiffer,stronger and are less complex(use fewer pieces) than the NSX.

Jaguar upcoming all-new XJ is going to have a state of the art bonded aluminum structure is not going to use welds, instead they are going to use aerospace adhesives, rivets and glues to join the pieces together...Rigidity of this car probably is going to be the best in the auto industry...

 

[JoeSchmoe]

Originally posted by ivan11:
Well i think titanium it could be used in several areas of cars..I have heard that in cars suspension springs,camshafts, valve springs,rocker arms just to name a few we could see the ...I don't think we will see it in structural parts of cars, but it can be used in different areas of cars..

As I said, I'd like to see honda use it sparingly and only where its needed. A lot of times, its just a marketing gimmick and it needlessly costs the consumer more money.

The aerospace industry uses titanium because shaving weight saves fuel costs. Over the years, the planes have already been shaved down to extremely minimal amounts. They go so far that the overhead luggage bins in the 777 are carbon fiber and supported by (what look like) forged aluminum arms! Hence, they are many times more likely to fork out the huge cost just to save a few more ounces.

In contrast, road cars have not been shaved anywhere near that much yet. In a separate thread about how heavy the NSX is, there are numerous examples of how "overweight" the car is. There are a lot of COST EFFECTIVE places for improvement and I hope honda and other car makers address those first.

Im not saying dont use titanium... just use it wisely.

By the way the Ti6 is not the strongest of all Ti.Ti10 and the ones in the Beta family are the strongest Ti!!!!!

True... some forms of 10-2-3 titanium are marginally stronger (5-10%) but I mentioned 6-4 because its used an order of magnitude more. Just like how 7068 is immensely stronger than 7075, its not really used or mentioned. The majority of titanium components and items out there are 6al4v. The only consumer application of 10-2-3 I can think of right now are golf club heads... =)

 

[JoeSchmoe]

Originally posted by Tony Montoya:
What is wrong exactly with welded aluminium?

Welded aluminum needs to be heat treated after welding in order to give the weld bead the strength of the surrounding material.

Look at it this way. A heat treated 6061-t6 beam is good for ~40KPSI. For comparison 6061-0 (untreated) is good <10KPSI. After you weld something, you pretty much ruin the heat treatment at the weld area and it will probably return to something closer to the -0 untreated state.

So, this means you either need to heat treat the entire chassis (?!?!?!?) to bring it back to full strength or you need 4x the weld bead. Thats one big oven or a hell of a lot of bead =)

Are the Supra guys right when they say the chassis will fail after a certain number of stresses?

True. Most alloys of steel and aluminum have a finite life with respect to stress cycles. Steel will not get "damaged" if you dont stress it past some "critical point". Aluminum, on the other hand, has a significantly lower critical point and most stress cycles will contribute to "damaging" the part.

Fortunately, it usually takes A LOT of cycles before something breaks because the chassis is stressed relatively lighly. If it will make you sleep any easier at night, the B-52 is largely aluminum and has been flying since the 1960's. We still see the very same 40 year old planes dropping bombs in Afghanistan.


What has been concerning me recently though is that the rear subframe on my NSX keeps getting loose. It will start creaking and groaning every 6 months. The dealer will retorque it and then it repeats in another 6 months. A loose subframe will not spread the load evenly to the chassis and may concentrate the forces onto the other corners. Not good....

 

[s2ktaxi]

I think if the body is stiff to begin with, it helps. Think of it this way. How much stress can you put on a solid block of Al to cause deformation? But obviously a sheet of Aluminum or an Aluminum rod is more easily deformed.

 

[ivan11]

Joe what is carburized treatment in steel?

The honda S2000 has forged and carburized connecting rods!!!!