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Bob Cosby

Is there a listing in there for professional driveline parts breaker? I have an awesome resume....

bossco

No kidding, I'm the grim reaper of automatics and thats not even making an effort to break them.

Borrowed my mom's Mustang GT and had the damn thing start slipping because I was cornering to hard!

On an off note, I think thats why I've only been able to get about 10k out of my rear brakes. I could swear that its loading the inside wheel as I go around the corner causing the pad to wear at an angle since the caliper is fixed to the housing and the rotor floats on the axle or maybe not.

I'd slow down and see if I could get them last longer (thus proving my theory) but I just have to much damn fun on the way home from work.

guionM

2 passenger cars that cost plenty? Sure.

4 passenger cars made in any type of volume? Not gonna happen unless you're talking about something the size of a Focus.

guionM

Dan... I have to tell you that this information is false.

I'm very aware that regardless as to what facts or information I share, I'm not going to convince you so I'm not really trying to right now. I'll be answering what you posted mainly to share info on the site


First guys, it's the IRS assembly that weighed 80 pounds more than the live axle on the '99 Cobra.

Second, Ford mandated 2 things to SVT when they approved development of an IRS for Cobra:
1) NO CHANGES TO THE MUSTANG STRUCTURE.. that included reinforcements.
2) They had to utilize the live axle's mounting points.

Ford managed to compensate for the heavier IRS by eliminating 110 pounds, 95 pounds of it up front.

Third, if anything, the IRS system in the Cobras were featherweights as far as IRS systems go. It used a welded tublar steel cradle, upper and lower aluminum control arms, an aluminium differential and wheel bearing assembly from the Mark VIII

Although I had access to certain key SVT people back then, all this information is easily availble by Googling (or even Yahooing) Cobra IRS, or 1999 Cobra.


I've noticed this "properly designed" fallback every time someone wants to make the case that IRS is lightweight, yet I never hear what properly designed means.

This term was created to slam the Cobra when certain people demanded IRS in the 5th gen Camaro. They said the Cobra was on a chassis that was designed for a live axle, and if a car was engineered from the start to be IRS it would be lighter.

Since then, almost every single car that's come out with RWD has been engineered for IRS.

Guess what?......It's even heavier.

So now, we're supposed to believe that even these cars with IRS are still not properly engineered for IRS????

BTW, the live axle Mustangs are lighter. Coincidence? Doubt it.

I suspect you've never taken a trip to a junk yard and see how these things are built, let alone had someone throw these things assembled on a scale to see for yourself what the weight difference really is. You can most likely have someone do it for 30 bucks, so it's not all that hard.

A live axle is a self contained tube. It has everything inside it. It is rigid so it can be mounted directly to the body.

IRS is mounted to a structure (typically a subframe or a cradle) that then mounts directly to the body. If you find a way to bolt the differential, halfshafts, & spindles directly to the rear floorpan without it I'm sure everyone is all ears.

FWIW, the closest you'd come is the last GTO/Holden V-body cars. They used what looked like a large lower control arms that anchored to the body under the rear seats and went back and anchored the outer parts of the halfshafts and contained the hubs while and the differential mounted to a small structure that bolted to the body. It still weighed 3700 pounds, despite being not much bigger than the SN94 Mustang.


Again, the term "properly designed".... and again, I ask what 4 passenger, rear drive, IRS, mass produced vehicle do you consider "PROPERLY designed"??

BMWs? Mercedes? Lexus? Infiniti? All these cars are heavy when put against same size IRS cars from Chrysler and GM. Camaro SS weighs 3800 pounds, but everything else in it size weighs more.

Again, the only exception is the live axle Mustang GT.

So empty space somehow equals more weight???

Not sure I'm following this.

You are talking about beefing up structures, which adds weight.
You say IRS is more structurally efficient (even though it requires it's own designated structure in order to be attached to the body (which also adds weight).

It's not the hardpoints that need to be beefed up. It's the bolt on assemby itself that carrys all the load. The thing bolts to the body in pretty much the same manner as the live axle does.

I wrote an unpublished story on the development of the D2C.

The short of it: Jac Nasser planned to take the Mustang upmarket and have both IRS and the small V8 from Lincoln (and a version supercharged). When Nasser was fired, pretty much every project he had stopped dead. When Mustang was restarted, it was changed significantly from Nasser's vision and went back to it's roots..

Everything in front of the "firewall" had to be reengineered because the DEW can not accept Ford's DOHC V8s (which were physically bigger than the Jaguar based ones that were in the LS and Thunderbird). The suspension up front was changed from control arms to struts which. Combined, everything up there has no resemblence to (let alone any structure of) the DEW. The rear was redone to accept both live and IRS setups. The stuucture above the floorpan had to be redone for the coupe. And finally, the whole structure is wider than DEW.

Essentially, the only thing carried over from DEW is some parts of the floorpan.

BTW: the "too expensive" part of the wiki info was directly related to the cost of the front suspension and IRS.


If the Camaro had been based on a Hyundai Genisis coupe, then yes, it would be lighter..... it would also be smaller.... and it also wouldn't be able to handle the 550+ hp of the ZL1 without the additional pounds added back on in components.

The weight of the steel needed to build a structure 189" long, 74" wide, and 55" tall in the same profile as the Camaro is going to be the same, regardless as to if it's origionally based on a Big car, or based on a Cobalt. It's what you hang on that chassis, and how much you want that chassis to withstand.

Camaro is barely bigger than a Mustang. Mustang is 188" long, 74" wide, and 56" tall. Camaros same measurments are 190" X 75" X 54". Camaro looks massive because it has a high belt line and a long wheelbase (112 vs 108).

Yet a DOHC V6 Mustang manual weighs 3453 while the same spec Camaro weighs 3780. 327 pound difference. With V8s and manuals, the GT weighs 3620 vs an SS' 3848, a smaller 228 pound difference (even though GM's LS3 is not much lighter than Mustang's 5.0). Ford themselves have said an IRS would add roughly 100 pounds to the Mustang, so the actual difference between the Camaro and Mustang's weight (all else being equal) is likely about 100-150 pounds. When you consider that the Camaro is rock solid in convertible form while Mustang flexes like a thin book, pretty much all debate about Camaro's weight loses a bit of heft.

The bigger part of the weight difference between Mustang and Camaro is the weight of their drivetrains, suspensions, brake systems, and "add ons" (ie: those 20" rims and massive tires) than the actual unibody itself.

Those Fox Mustangs needed aftermarket chassis reinforcements if you wanted to pump more than 300 horsepower through them. They were available through the Ford performance catalogue. Today, base V6s put out more than that.

The new 1994 SN Mustangs gained weight because of a stronger body structure and better handling and balence (the Fox based GTs would be considered dangerous today... and they only had about 200-220hp).

The 2005 Mustang gained weight because it grew in size.

The 2008 gained weight to gain more strength and to prevent some firewall and floorpan cracking that showed up in some cars after heavy use.


So, BMW (of all carmakers on the planet) created a pig because their 2011 M3 414hp V8 weighs 3700 pounds, while 30 years ago a BMW E30 with a 190hp FOUR CYLINDER ENGINE weighed 2800 pounds??!!!

Forget the added NVH, safety, comfort & convience items that have wound up in cars over the past 30 years, you're using a 4 cylinder RWD car to prove that a high powered RWD V8 can be just as light???

Come on... Really??!

Again, a very small sized 4 banger doesn't make a weight point for a big high poweredV8.

If that's what you want Camaro to be, then sure I'll agree that Camaro can be a 2700 pound 4 cylinder car about the size of a Focus with IRS. But I thought we were talking about 400+hp V8s with IRS.

You seem to be confusing the issue as there are no examples to support the position.

Overweight? Again you make this assumption without any vehicle to prove it.

What vehicle of the same size, and power with IRS can you show us here that proves the G8/Commodore is overweight???
Find another 2 door coupe on the planet that is the size of Camaro and weighs substantially less that has IRS??.

You are refering to 40+ year old economy cars with live axles. I thought we were talking about modern, IRS RWD cars that can handle 400-500+ horsepower.

You named 2, co-owned by Toyota and Subaru. Miata is also based on a small lightweight platform, as is the R8. None are V8s. All are smaller than the Chevy Cruze.

And, again this goes back to the points I continually make. What are we prepared to give up to get weight down?
Size?
Dropping V8s?
Going back to tiny brakes?

The old iron block and head Ford 5.0s weighed 411.
The old LS1 is 430 pounds.
GM's current aluminum block LS3 engine has a shipping weight of 468 pounds (LS6 is 458).
Ford's new 5.0 Coyote engine has a shipping weight of 479
Chrysler's iron block 5.7 Hemi weighs 485 (it lost additional weight with the 2009 redesign)

While the LS3 is slightly lighter than it's competitors (a mear 17 pounds off of the Hemi), it's still 38 pounds heavier than an LS1 (and has 55 over the old 5.0s), so lightweight is streching it a bit.

See above.

With a 4 cylinder engine, the new ATS weighs just under 3400 pounds... that's about 400 pounds under the V8 Camaro.

My guess is that the base ATS 4 banger engine weighs around 275 pounds, so the difference with the V8 is about 200 pounds. Bigger radiator, fan, and additional fluids, probably another 20#. The beefier Borg Warner 6 speed is likely another 70 pounds up. Beefier differential and halfshafts, perhaps 15#. Upsized brakes (but smaller than the ones current on Camaro) probably another 30 pounds or so.

That's about an additional 335 pounds, bringing it to about 3700 pounds with a V8. About 150 pounds lighter.

Even if my math is wrong, it's obvious you simply aren't going to see a 400 pound loss in a Camaro carrying over the V8 engine.

100-200#? Likely.

But again, you're talking about a car that's barely bigger than a Cruz.

guionM

I've had a longstanding open invatation to anyone who feels the camaro (or G8/Commodore, Challenger, Charger, or 300, or even Mustang) are overweight to show a comparible car that's significantly lighter that has the same things is the same class, and handles the same power. I first laid that out about 6 years ago.

Corvette comes up frequently. however, Corvette is a 2 passenger sports car that is barely taller than one's waist. If there's a way to seat 4 people (let alone 5) comfortably inside one, I'd like to see it. Point is, it's almost silly using it as an example. I don't even need to go into detail about what it costs to make one of them.

The other thing that frequently comes out is some car of the 1980s, usually a 3rd gen Camaro or a Fox Mustang. In case no one noticed, the 80s were 30 years ago now. Breaking 200hp was a very big deal back then. Mustangs were light, but nortoriously flimsy. The best stopping Camaros had brakes that look like they belong on a Miata today. By today's standards, the systems on 5.0 Mustangs wouldn't even qualify as brakes... a lower gear, maybe, but not something to actually stop a moving vehicle. The NVH in those cars wouldn't even pass in bottom feeder Kias today. And anyone who has seen a Fox Mustang in a head on, or a T-bone accident will never want to get into one again.

The next thing that comes up is how someone... in their back yard... stuck some engine or another in their car and had no problems. Well, there's a couple things missed here:

1) That is because all vehicles was overengineered enough to pretect themselves from lawsuits when you abuse your car. That engine swap is abuse, and you just used that cushion if you didn't exceed it.

2) The vehicle you buy in a showroom has to not only last the length of a 100K mile warranty, but also has to do it for quite a bit beyond. If someone buys your backyard project, you going to cover repairs on it for the next 6 years? No matter how hard I drive it? Didn't think so.

The final thing that repeatedly comes up is some current car that is so far removed from the conversation that one wonders if the person just came in the middle of it. Miatas are barely bigger than go-karts and have 4 cylinder engiene. RX8s have no torque, and therefore no real need to have an industrial strength drivetrain. The Toyoburus are tiny. They also have 4 cylinders. How tiny? It makes the 130R concept look big.

When everything is disproven, we get into this elusive "if there was a Properly designed IRS....". Problem is, no one ever defines it. No examples are ever produced of one in mass production.

Even some of the best, most renouned, engineering savy car companies in the world suddenly are producing "Pigs" and don't "Properly design" because they are "lazy' or simply "don't challenge themselves". This view usually comes up after the Corvette, the 80s vehicle (which is almost always a live axle car), the small rear drive 4 bangers, and the back yard cars run their course.

Everyone has access to the curb weights of every car made on the plenet earth via the internet, so it's no secret that the Zeta is actually lighter than just about any RWD-IRS-V8 car it's size. Ditto Camaro. The BMW M5 is the same size as a Camaro SS, but it weighs more than the bigger Challenger R/T (which has an iron block V8!). Fact of the matter is that we have these cars as light as they are at all!

There is a number of conclusions to be drawn by all this.

1. If it was as easy as some people make it out to be, it would have been done by now. Even luxury car companies that can afford to pour magnesium into their cars don't have lighter IRS cars than GM. That should tell you something.

2. It's going to always take a certain amount of steel to do a certain job. You have a bigger job (more performance) it's going to take more steel. A ton of steel weighs as much today as it did 30 years ago. In an earlier post on this thread I showed just how much just transmissions have grown in weight, as I did brakes and other components. More power=more weight through stronger materials.

3. There's no free ride, there's no miracle metal, there's no magic wand. V8 powered, 400+hp, rear drive cars with independent suspension are going to be heavier than live axle cars. Period. You can do what Ford did with the 1999 Cobra, and try and make up the weight by losing it somewhere else. That's what Ford is trying to do with the 2015 Mustang as we speak. It's all a matter of priorities and what you're willing to sacrefice.

We can easily get back to a IRS car that weighs as much as a 5.0 Mustang of the 80s. But it's going to have the same power as well... through a turbocharged 4 cylinder engine... and be the size of the 130R.

Want to lose 400 pounds off of an SS? Build the car around the 3.6 V6 as top power. Then weight can be taken out of the drivetrain, brakes, cooling, the suspension and it can be put in a Genisis coupe size package.

I encourage everyone who has nothing to do one day but watch the grass grow, swing down to a junk yard. Check out the weight differences in brakes. Check out the real differences between IRS and a live axle. Give the guy a few dollars to throw a live axle (as bolted to the car) on a scale, and do the same with an IRS assembly. Or if you have excess computer time, do a search on the weights of certain car components.

Can't find it? Look up someone at whichever car company and shoot them an e-mail question on the weight of whatever you want to know (they'll forward it to someone who can answer your question) or stop at a dealer parts counter on one of their slow days..

That's how I got started in this hobby.

Dan Baldwin

Busy weeks ahead, will address further later.

Long short, Gen5 is NOT a 3850 lb. due to IRS and 400+hp V8, but rather because it's a giant heavy sedan platform. Start with a big/heavy platform = little/no hope of smallness/lightness.

Regarding Cobra IRS: The point you bolded is EXACTLY the point I've been making. They had to build a BIG and heavy subframe to beam loads from IRS control arms and diff support to a chassis designed for a live axle. You wouldn't do that in a dedicated IRS design. The IRS is HUGELY compromised in order to be a swap-in on a live-axle chassis.

Regarding modern M3 vs. 80s M3, the 3-series is a VERY different car now. It is primarily a luxury car, whereas the 80's 3-series was a much smaller more minimalist car.

That BMW isn't building small, lightweight, minimalist rwd/irs cars doesn't mean it isn't possible.

The next Mustang will have a chassis designed around IRS, and will have the 5.0. Targeted weight savings is 300 lb. I'd expect something like half that to be realized, so figure ~3450 lb. rwd/irs with 400+ hp V8.

Lighter-weight rwd/irs 400hp cars can be built if the will is there. We shall see how much will Ford has. I wish them the best for the 2015.

Also have big hopes for a 6th gen Camaro after, for me, they went in entirely the wrong direction for the 5th gen. They have certainly sold well, so either way, at the very least there are a lot of donor cars out there for me :P

Here's to a smaller and lighter-weight rwd/irs V8 future for the pony cars...

jg95z28

It's never going to happen. If you want smaller and lighter-weight RWD, you're going to have to learn to live without a V8. Those are the cold hard facts. Some folks are just too hard-headed to understand that just because you can dream something up, doesn't mean that you can overcome the physics behind making it a reality. With modern V6s making north of 300hp, do you really need a V8 in a smaller and lighter-weight pony car platform? If you don't want to give up the torque of the V8, what about a turbo-diesel option? There are plenty of alternatives out there, but they all require giving up a gasoline powered V8.

Z28Wilson

Yeah well, the problem is that it seems nobody wants a 'minimalist' car anymore. The 5th Gen has a freakin' backup camera. I mean really? I thought this was a Camaro, not a bluehair's Caddy. Sadly though, that's just the market we're living in these days.

I have resigned myself to expect the 6th Gen will be smaller and lighter, but it won't be a shocking difference. It's still going to be tech-packed and big horsepower capable because that's what (most) people want.

Bob Cosby

Yup, I'm with ya on that one.

bossco

What would a "minimalist" Mustang or Camaro cost these days? And I'm not talking some sort of small run either, rather if there was a large enough audience to entertain crank windows, manual locks, no ac, no infotainment, base interior, et al coupled with a moderate amount of power (say no more than 300hp) with styling based around 16 inch wheels so that unsprung forces could be kept in check without the need for brute suspensions ( no point in saying simple suspension since complex is de rigueur) and super hero brakes.

I suspect it would still grab a substantial portion of the average person's income making such a car hard to justify.

The toyobarus probably are the closest to what most people consider a minimalist car today

After watching this guy despite being at opposite ends of the spectrum both cars produced the same result - big grins.

2013 Ford Shelby GT500 Chases 200 MPH! - Ignition Episode 18 - YouTube

2013 Scion FR-S: A New Hope? - Ignition Episode 14 - YouTube

jg95z28

If brand doesn't matter, what you guys are looking for is already available in a RWD ponycar. It just doesn't have a V8.

2013 ponycar = 3400 lb & 275-350hp

Bob Cosby

...and therefore I have zero interest in the car.

Z28Wilson

Or the heritage. Or the muscular styling. But yeah, on paper the formula looks good to me. Wonder if that structure could be certified to hold a Gen V smallblock.

96_Camaro_B4C

There is also the Mustang V6, which (when properly equipped) can rip off acceleration times right with (if not a tick quicker than) LT1 F-body times. The V6 Camaro RS is just a smidgen behind an LT1...