They haven't through factory reliability/durability testing that we know of. Then again, the Z has never come with that level of power, so perhaps they would. Hard to say.
2014 Mustang to have IRS
- Thread starter Jack Burton
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They haven't through factory reliability/durability testing that we know of. Then again, the Z has never come with that level of power, so perhaps they would. Hard to say.
Yeah, but I see a lot of as tested weights up around 3,400lbs. I think Nissan is fibing a little on that figure.
2010 Ford Mustang vs. 2009 Nissan 370Z Comparison Test on Inside Line
The car only makes a relatively wimpy 270ft-lbs. of torque also.
The E46 is a good comparison, but I think still smaller than the Mustang and again you are talking about a V6 that only makes 260ft-lbs. of torque.
The new M3 (which meets modern safety standards and has a V8, although a tiny one) weighs 3,700lbs and still only has to handle 300ft-lbs. of torque.
I am not saying it isn't doable, just that it is going to be very hard to do it and keep it cheap. Light and cheap don't go together. As you see we are already talking about M3's for crying out loud!
Not everybody drag races.
The Terminator was designed as a road racer. 1320 guys yank go-fast parts, destroy a great car to fast in a straight line... What?
Maybe you'd like a DeDion rear end set-up to sitting next to an old Vette/pre '68 Volkswagen swing axle on display inside the old museum next to that purdy live axle?
LoL
Jeff
i agree - i just recently did bruce's full kit, and while there is no noticeable difference just driving around normally, on-ramps and turns now are so much more fun. almost like the car has less understeer and the rear end just rips around so i can turn in that much more without it pushing. i may be wrong (i have never road raced), but i can really tell a difference in street and highway high speed turning
when i took the rubber bushings out, yes, they had alot of preload in the rubber, and the whole arm was difficult to articulate by itself. both uppers and lowers, but especially the uppers
Only for about two laps. You have to watch the heat soak to avoid limp. Later the rear diff mount bushings will melt, and the diff oil will boil out all over and down onto the exhaust, causing you to be black flagged.
Now there are fixes, rear diff cooler and solid bushings, but just sayin'.
You don't need the IRS on a road course unless it's a very bumpy course or you are so all-out and experienced your car is pretty much a dedicated track car and you can completly re do the rear end.
A solid axle is just fine for most us, even those who open track on road courses.
Hmm, that doesn't sound right. My buddies 350Z doesn't even weigh 3400lbs and the 370Z is definitely smaller! It's a 2 seater that's smaller than even a C6. :shrug:
As for the E46 and Supra, they both have handled well over 800 ft/lbs of torque.
I don't feel the weight of the IRS necessarily go hand in hand with how much torque it can handle.
Also, the E46 M3 and newer E9X M3s could weigh a lot less but they too share a platform for midsized luxury sedans.
Well that I agree with that, car manufacture's are already complaining that the increased fuel requirements will definitely increase costs. I'm talking about M3s and Supras, but mind you these are already 9-17 year old cars! The technology isn't as cutting edge and expensive for a 2014-2015 model car.
If a new platform is designed from the ground-up with weight limitations in mind it can most certainly be done. Checkout the Cadillac ATS built on the Alpha platform which is rumored to be shared with the next generation Camaro.
I think we will see lighter as well as smaller cars in the future. Which is okay by me, IMO, the new Camaro, Mustang and Challenger are a lot bigger than they need to be.
My buddies Turbo 350z with mild weight reduction weighed in at 3,46X if I remember correctly last time we were at the track. Not sure how much gas, but he did have the added weight of the turbo. I have always thought/seen that the Z cars are not as light as one would think. For that matter, as light as they should be.
All good points and I don't think they necessarily go hand in hand either. Its just an observation I made. Both the Cobra and Camaro appear to have heavier rear suspensions than the 350z and older M3. It would be cool to find some actual weights of the Z and M3 IRS for a true comparison though. We've got weights for the Cobra and Camaro.
I know these cars have handled a lot more torque than they were designed for (so have many cars), I just wonder how much the design would change if the factory was producing the car/rear for the levels of torque the Camaro and Mustang make. Factory acceptance tests are far different than what an owner deems acceptable. Its just a thought.
I think that may be the key. Smaller cars will make it easier to save weight and boost performance and fuel economy without significant increases in power. I tend to think the Mustang is a good size, but could shave the rear overhang some. The Camaro and Challenger both need to get smaller in my mind.
If you stay at the factory boost level I don't think heat soak should be much of a problem. If you run a more efficient blower than a stock Eaton you should be able to run more boost without getting into heat soak as well. Also get a very safe tune.
I do agree that the SRA has a lot of potential just not with the geometry of the factory 4 link. If I was to get a SRA car I would probably do a Steeda 5 link 2. I really like its design, but the torque arm/panhard bar or watts link/ no uppers is a proven setup as well.
I wouldn't change the IRS for a straight axle on a IRS equiped Cobra though unless I was pushing a ton of power, and or DR'ing it frequently.
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Sounds about right for a 350Z, generally 3325-34xxlbs stock depending on options. The 370Z is smaller though. They made the rear-end considerably shorter.
I see what you're saying. Although we have no figures on factory acceptance tests for the rear-suspension setups. For example, the Supra makes 315ft/lbs stock, but it's been proven reliable well over 700ft/lbs. That rear-suspension could easily be more than enough in a 500-600hp+ factory car.
I think the Mustang could be a little smaller, especially if they decide to dump the retro theme in the future. :beer:
Yeah, they did a lot of work to lose weight in the 370Z, but still lost less than 100lbs. if I remember correctly. I think it was around 80lbs. all said and done.
Part of the reason it looks smaller is that the hatch rolls all the way to the rear of the car instead of ending before it like it did on the 350Z. I like these cars and know several owners of them and have ridden on track in one. They are very nice little cars, but certainly not lightweight. My darn Camaro weighs less than a 350Z and thats with spare tire, jack, and 3/4 tank of gas.
Anyhow, this does not necessarily lead to the IRS being heavier in a Mustang. However, the only similar data points we have to go on are the 03/04' Cobra IRS (~150lbs. over a SRA) and the Camaro IRS (~185lbs. over a 12-bolt SRA). So......absolute best case the IRS adds only 100lbs.????
Even at the factory boost level and very rich (factory) tune, it did go into limp when pushed. But yes a twin screw, low boost, and rich tune would do better.
The steeda 5-link or the torque arm/panhard bar/watts link set-ups are superior to the Ford 4-link no doubt.
:lol: the stig.. LOL your awesome.
Yes, marginally. It improves the ride on a bumpy surface and reduces side-stepping on bumps mid-turn. (Had an 03 Cobra for 3 years)
There isn't much of either on road coursess. Plus on a road course the rear bushings will melt and fluid will boil out onto the exhaust if you drive it anything but easy. So it sucks for road courses unless you change out all the bushings and add a cooler.
It also sucks on drag strips because again, all the bushings should be replaced and it adds much weight. More prone to breakage too.
The IRS improves ride quality on the street. But you will have to put up with "the clunk" and often extra vibrations.
A steeda five link, torque arm set up, or Fords own three link is the way to go in a Mustang.
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And the street is where the vast majority of cars are actually driven ...
Ahh but the difference is I don't care much how comfy the ride is. Otherwise I'd drive a Crown Vic. I could certainly spend $3K on my cars' suspension and really enjoy it. It would ride harsher and I would not care. But the $3k is better spent towards a newer, all over superior car.
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