Dodge Viper ACR runs a record-breaking 7:22 lap around the Nurburgring

[lucid]

That Radical SR8 ride is radical.

[footie]

Originally Posted by lucid

That Radical SR8 ride is radical.

Yeah, but it's no harsher than the big Viper. And I know which one I would prefer to be driving, the Radical is a scalpel to the Viper's hatchet.

[skierman64]

I wonder what tires were used for this lap. It was probably either full out race rubber or DOT legal race rubber.

[ace996]

Originally Posted by footie

ace996,

If you want a cheap, industrial, -please tell me you make those statements based on something other than the video. Personal experience, a friend who has one, test drives you've done, perhaps ever seeing one in real life....please tell me something other than watching an ACR from an in-car camera o the Ring whilst breaking the record is what you base that comment...please???uncompromising trackday car which is hellish quick then by all means buy the Viper. Like I said on the other post, national pride is clouding your judgement -footie, the car did a 7:22...that has nothing do to with my National pride. I've driven Vipers, has nothing to do with National pride. National pride has nothing to do with the two BMWs in my driveway, or the Subaru and Lotus that was there before. May I ask you to examine your distaste and, perhaps, knee-jerk reaction to your ACR-hate and determine just howyou come to make such dismissing comments???. Again, your personal experience with a Viper?and in this I can understand, I too would be feeling the same especially as American is the butt of all jokes when it comes to handling.-that's funny, I bet CorvetteRacing is laughing their asses off after beating everyone for years...

But like I keep insisting, making something handle well is not the difficult part, making it handle and still feel like quality, ride well and have finesse in it's controls is what separates the good from the brilliant. Viper is the good and the rest that are up around it are the brilliant.-well, when those brilliant cars get their asses handedto them in the various classes of racing, they can always sit back and revel at how well their, as you perceive, controls and switches work.

You mention all the other brands I listed as ultra expensive to own and run and you are quite correct, the reality is that quality costs money, lots of it. That is why when one tunes their 335i they may achieve similar results as the M3 but it's no M3 and that is the thing, the Viper is the 335i and the GTR and others are the M3.-and you may just be missing the point...Dodge didn't build the ACR to compete with the EuroBuilders' cars on daily driveability, they built it to be a potent race/track car...of which it has done brilliantly.

If you were to put the Viper up against a car which is closest to it is philosophy then pick a Radical SR8, price would be similar and both can be driven on the road -not here...that's not a street car here. but the Viper would finish a distant second in any race that didn't involve maximum speed.

Feel free to disagree -guy, I couldn't disagree with you more. You compare an open cockpit "kit car" to a Dodge ACR. Really, think about this...an open cockpit kit car that requires a full-face helmet to drive vs a production-based car....I'll bow out of this discussion now so as to not to appear personally confrontational but to me these cars are closer than any of the others,-I would bet that you've never seen a Viper with your own eyes...is that true? Have youever driven one? it too is totally uncompromising, though with it you are getting a quality in it's controls that the Viper could only dream of. (again, your basis for making such a claim?)

Be good,
TomK

[footie]

My experience of the Viper is restricted to a spell in the passenger seat about 5 years ago and the experience was not what I was expecting. The Viper was about the worst built piece of shit I ever sat in, for the £75K (yeah that's right ($140K)) they were looking I was gobsmacked just how poor everything about it was. Sure American cars in general aren't built to the same standard that most quality European brand are but this thing took the biscuit.

The ride quality, a very loose term when used with the Viper was awful, if you had placed a coin on the road surface I bet you would have felt in through your backside. Yes I might have a very negative opinion of the Viper but the same doesn't include the Corvette, especially the latest versions which have addressed many of the failings that separated it from other European exotics.

Accept that the Viper isn't built for any purpose other than going quickly on a track and gives no compromise for driver or passenger comfort compared to the other cars that's times are just below it and we will have at least come to a compromise of opinions.

P.S.
The Radical is no kit car, far from it. The quality of the controls and equipment used is of the highest standard and it covered the same lap almost 30 seconds quicker with an engine barely bigger than the starter motor of the Viper.

GB 1 - USA 0.

[swamp2]

Originally Posted by bruce.augenstein@comcast.

As long as you are narrowly defining quality as a more or less NVH thing (one of many possible definitions), then I can't find fault with your logic.

Bruce

The other visible metric of quality would be the sizes and fit of all the shifter linakge bushings/bearings. They clearly suck. I call that a design and quality issue.

[bruce.augenstein@comcast.]

Originally Posted by swamp2

The other visible metric of quality would be the sizes and fit of all the shifter linakge bushings/bearings. They clearly suck. I call that a design and quality issue.

Wait a minute! Is that what you meant when you said "loosey-goosey shifter"?

OK, figuring perhaps I missed something, I went back to the video, and watched it twice more, front to back - and found absolutely zero reason for you to think the way you do. In fact, shift action seemed routinely crisp throughout.

I hereby challenge any and all readers of this string to find a trace of the slop in the shifter that Swamp finds to be evidence of poor quality.

Swamp, what you're referring to is engine/transmission movement caused by 500+ foot pounds of torque fed through non-solid motor mounts. You'll find similar movement in a Z06, or in fact any other big-inch, high-torque engine/transmission combo. The linkage, having been bolted directly into the transmission in this case, faithfully follows along.

It simply isn't a quality issue. It's the nature of the beast, and the only way around it is to go to solid engine and transmission mounts, which when installed in any street car will make it feel as if you're sitting in a blender.

OK, I stand corrected. You could also theoretically remote mount the shift mechanism (only by redesigning this particular box, however), but you would only do this if shift quality akin to stirring a bucket of rocks with a baseball bat was your design goal.

Bruce

[bruce.augenstein@comcast.]

Originally Posted by skierman64

I wonder what tires were used for this lap. It was probably either full out race rubber or DOT legal race rubber.

Pilot Sport Cups, standard on this car (along with the Porsche GT2 and GT3).

The standard Viper uses custom PS2s - with Sport Cup tread compound.

Bruce

[swamp2]

Originally Posted by bruce.augenstein@comcast.

Wait a minute! Is that what you meant when you said "loosey-goosey shifter"?

OK, figuring perhaps I missed something, I went back to the video, and watched it twice more, front to back - and found absolutely zero reason for you to think the way you do. In fact, shift action seemed routinely crisp throughout.

I hereby challenge any and all readers of this string to find a trace of the slop in the shifter that Swamp finds to be evidence of poor quality.

Swamp, what you're referring to is engine/transmission movement caused by 500+ foot pounds of torque fed through non-solid motor mounts. You'll find similar movement in a Z06, or in fact any other big-inch, high-torque engine/transmission combo. The linkage, having been bolted directly into the transmission in this case, faithfully follows along.

It simply isn't a quality issue. It's the nature of the beast, and the only way around it is to go to solid engine and transmission mounts, which when installed in any street car will make it feel as if you're sitting in a blender.

OK, I stand corrected. You could also theoretically remote mount the shift mechanism (only by redesigning this particular box, however), but you would only do this if shift quality akin to stirring a bucket of rocks with a baseball bat was your design goal.

Bruce

Yes, that is what I meant by loosey-goosey. Especially when he kept banging it off the limiter near the beginning of the vid. I suppose I could be wrong here, especially having never driven a (nor many) vehicle with the torque of this car I guess that makes be a bit unqualified. As well my last post is very likley dead wrong. However, I still have a very strong suspicion that there are high torque MT vehicles that don't have a shifter that moves left to right, while in gear, almost as far as a shift.

Think about it another way...Many vehicles out there have 1/2 - 3/4th of the torque of the ACR (heck the lil' ol M3 has over 1/2). And... miraculously... you do not see 1/2 of that movement out of these transmission levers. Do you? There must be a solution other than those you mention that won't cut it.

I suppose a more sophisticated "soft" rev limiter would have helped as well. But again too sophisticated for Dodge...

[M3WC]

Originally Posted by swamp2

Yes, that is what I meant by loosey-goosey. Especially when he kept banging it off the limiter near the beginning of the vid. I suppose I could be wrong here, especially having never driven a (nor many) vehicle with the torque of this car I guess that makes be a bit unqualified. As well my last post is very likley dead wrong. However, I still have a very strong suspicion that there are high torque MT vehicles that don't have a shifter that moves left to right, while in gear, almost as far as a shift.

Think about it another way...Many vehicles out there have 1/2 - 3/4th of the torque of the ACR (heck the lil' ol M3 has over 1/2). And... miraculously... you do not see 1/2 of that movement out of these transmission levers. Do you? There must be a solution other than those you mention that won't cut it.

I suppose a more sophisticated "soft" rev limiter would have helped as well. But again too sophisticated for Dodge...

It would be nice to see a video of another car with this amount of torque, that is bouncing off the rev limiter.

The thing is not many cars out there are mapped like the ACR and would not be riding the rev limiter like that.

This is just a unique case.

And like you said, you can't really pass judgement unless you can drive one.

[swamp2]

Originally Posted by JetBlack5OC

And like you said, you can't really pass judgement unless you can drive one.

Hmmm, I didn't quite go that far. I am passing judgements.

As well, in general, I am a firm believer in being able to make many judgements without seat time, some require it but many don't.

[M3WC]

Originally Posted by swamp2

Hmmm, I didn't quite go that far. I am passing judgements.

As well, in general, I am a firm believer in being able to make many judgements without seat time, some require it but many don't.

I guess you meant something else with this statement.

Originally Posted by swamp2

I suppose I could be wrong here, especially having never driven a (nor many) vehicle with the torque of this car I guess that makes be a bit unqualified.

[bruce.augenstein@comcast.]

Originally Posted by swamp2

...However, I still have a very strong suspicion that there are high torque MT vehicles that don't have a shifter that moves left to right, while in gear, almost as far as a shift.

Think about it another way...Many vehicles out there have 1/2 - 3/4th of the torque of the ACR (heck the lil' ol M3 has over 1/2). And... miraculously... you do not see 1/2 of that movement out of these transmission levers. Do you? There must be a solution other than those you mention that won't cut it.

First off, let me correct myself in regard to the Z06. I was thinking big-power and torque cars and just fired that one off, but I thought back to my time in the car, and in fact the Z06 doesn't exhibit any shifter wiggle during significant power-on, power-off inputs - for obvious reasons when you think about the rear-mounted transaxle.

Next, let me advise you to think about engine mounts, what they do, and the very basic principles involved. The thing is, you're trying to suppress individual firing impulses, and you can't just stiffen up the mounts by, say, 50% to suppress 50% more energetic pulses, or else the mount stops effectively doing what it's supposed to be doing, and you get that sitting-in-a-blender feeling. So you're going to get more engine/transmission movement in a longitudinally-mounted layout with high torque than with a lower torque application.

Last, and at a complete guess, the Dodge guys may very well allow a bit more shifter movement than the absolute minimum because it would be in keeping with the car's overall persona, which more than anything else is the "Wow, what power!" feeling the vehicle conveys - combined with a studied lack of NVH control.

Originally Posted by swamp2

I suppose a more sophisticated "soft" rev limiter would have helped as well. But again too sophisticated for Dodge...

Perhaps. But it's equally possible that the engineering types eschewed such a girly device in such a manly car.

Really.

Bruce

PS - I suppose I shouldn't be surprised at such passionate positions in regard to NVH, given the forum, but even the normally mild-mannered and astute footie has been inspired into a bit of uncharacteristic (I hope) nationalism. Who woulda thunk it?

PPS - If Dodge was crazy enough to knock all the rough edges off the car, they'd probably lose about two-thirds of their base, and have to hope BMW guys would come flocking to the dealerships, frantically waving cash.

Yeah. And I can hear pig wings warming up on the runway.

[swamp2]

Originally Posted by JetBlack5OC

I guess you meant something else with this statement.

Yes, and you would see that if you read exactly what I wrote. But let me clarify and expand without contradicting.

1. I do not have direct experience with this vehicle nor others that have the same amount of torque. That makes me in some senses unqualified to speak to specific experiential aspects of such cars or what the norms may be in such cars, especially on some NVH issues.

2. Despite not having driven this car I still am of the opinion that both the behavior of the rev limiter and the vibration and total magnitude of movement of the shift lever is excessive and could be avoided through a better design. I think many watching the video, despite having never even seen an ACR could reasonably come to the same conclusion.

Switching gears slightly...

I think I agree with Bruce just above. Both of those issues are probably at least in part by choice or design. Nonetheless, I can't help but believe these things distract from the ability to precisely control the vehicle esp. the shifter in some small but quantifiable way. That may be as subtle as just being a major distraction or perhaps numbing to your hand over the long term. It may also be as overt as the lever becomes more difficult to move under load or it can not be moved as quickly. Call it design, call it quality, maybe some of both, one can not really answer the question without speaking to those very close to the design and engineering and none of us likely will.

[swamp2]

Originally Posted by bruce.augenstein@comcast.

Next, let me advise you to think about engine mounts, what they do, and the very basic principles involved. The thing is, you're trying to suppress individual firing impulses, and you can't just stiffen up the mounts by, say, 50% to suppress 50% more energetic pulses, or else the mount stops effectively doing what it's supposed to be doing, and you get that sitting-in-a-blender feeling. So you're going to get more engine/transmission movement in a longitudinally-mounted layout with high torque than with a lower torque application.

Sure about that? I don't think so. I think engine mount stiffnesses are governed more by the total magnitude of the twisting torque of the engine. Sure that is the result of many individual firings but I bet you could not pick up those really high frequency signals in say the resulting lateral movement of the gear shifter. Lots of magic can be worked with suck things including stiffness, non-linear stiffness, damping and totally different performance for translational DOFs vs rotational DOFs. In short I'd be willing to bet any decent NVH engineer could prevent the vast majority of this "unwanted" shift lever movement while not making you feel in gory detail all of the NVH from the engine.

Anyway, I think we finally, basically, agree - part intent, part lack of attention to NVH.

[bruce.augenstein@comcast.]

Originally Posted by swamp2

Sure about that? I don't think so. I think engine mount stiffnesses are governed more by the total magnitude of the twisting torque of the engine. Sure that is the result of many individual firings but I bet you could not pick up those really high frequency signals in say the resulting lateral movement of the gear shifter. Lots of magic can be worked with suck things including stiffness, non-linear stiffness, damping and totally different performance for translational DOFs vs rotational DOFs. In short I'd be willing to bet any decent NVH engineer could prevent the vast majority of this "unwanted" shift lever movement while not making you feel in gory detail all of the NVH from the engine.

Anyway, I think we finally, basically, agree - part intent, part lack of attention to NVH.

Swamp, when I advised you to "think about engine mounts, what they do, and the very basic principles involved", it's clear you blew that off. To say that the preeminent idea behind engine mount stiffness would be total torque is so, so, beneath you, that I'm sure of my ground on this.

We don't need to discuss this tiny little off-topic issue any further, but when you have three minutes and the inclination, just consider the issue.

Bruce

[swamp2]

Originally Posted by bruce.augenstein@comcast.

Swamp, when I advised you to "think about engine mounts, what they do, and the very basic principles involved", it's clear you blew that off. To say that the preeminent idea behind engine mount stiffness would be total torque is so, so, beneath you, that I'm sure of my ground on this.

We don't need to discuss this tiny little off-topic issue any further, but when you have three minutes and the inclination, just consider the issue.

Bruce

No I didn't blow it off. Your reply sounds only like arrogance or insecurity. I am open to hearing your lecture on engine mounts. Nothing wrong with minutia and slightly OT on m3post.com!

To continue the point I did not say that THE most critical thing for a mount is its ability to resist torsion. You seem to have a remarkable ability to misrepresent my words. I just believe that is a much more important factor than the effect of individual combustion pulses. Mounts have many functions, both structural and NVH, both static and dynamic, and in terms of rotational and translational DOFs. They play roles in the reduction of structure-borne noise as well as airborne noise (indirectly by source reduction). Again, I'm very open to learning more about them.

[bruce.augenstein@comcast.]

Originally Posted by swamp2

No I didn't blow it off. Your reply sounds only like arrogance or insecurity. I am open to hearing your lecture on engine mounts. Nothing wrong with minutia and slightly OT on m3post.com!

To continue the point I did not say that THE most critical thing for a mount is its ability to resist torsion. You seem to have a remarkable ability to misrepresent my words.

You said, "I think engine mount stiffnesses are governed more by the total magnitude of the twisting torque of the engine."

Yeah, misrepresent.

Originally Posted by swamp2

I just believe that is a much more important factor than the effect of individual combustion pulses. Mounts have many functions, both structural and NVH, both static and dynamic, and in terms of rotational and translational DOFs. They play roles in the reduction of structure-borne noise as well as airborne noise (indirectly by source reduction). Again, I'm very open to learning more about them.

Beginning of lecture:

1) Engine mounts (meaning those that aren't just brackets) have a single function, which is to reduce NVH.

2) You don't stiffen a mount in an effort to control engine pulses of a larger magnitude. If anything, you might even make it more resilient - and thus have more engine movement rather than less.

End of lecture.

Bruce

[ace996]

Originally Posted by swamp2

It may also be as overt as the lever becomes more difficult to move under load

...short of speed/power shifting, when is the shift lever ever moved "under load"?

Even if there is "load" whilst shifting, it's the transmission housing that is shifting, not the internal shifting mechanism.

I have had vehicles of more than 500hp/tq, one was a supercharged Vette...that did not have a dancing shifter. The other was a CTS-V, only 400tq, but it did have the dancing shifter. My friend's supercharged CTS-V, dances even more...even with ashort shifter. Shifting effort is not increased or shifting compromised.

Be good,
TomK

[swamp2]

Originally Posted by bruce.augenstein@comcast.

You said, "I think engine mount stiffnesses are governed more by the total magnitude of the twisting torque of the engine."

Yeah, misrepresent.



Beginning of lecture:

1) Engine mounts (meaning those that aren't just brackets) have a single function, which is to reduce NVH.

2) You don't stiffen a mount in an effort to control engine pulses of a larger magnitude. If anything, you might even make it more resilient - and thus have more engine movement rather than less.

End of lecture.

Bruce

Nonsense on both points. 1. Yes you misrepresented what I said, if you can't see that you can't read. 2. Depends on what you are trying to control, there is not one, simple reductionist answer to the question of how does an engine mount for a high torque vehicle differs from that for a low torque vehicle.

[bruce.augenstein@comcast.]

Originally Posted by swamp2

Nonsense on both points. 1. Yes you misrepresented what I said, if you can't see that you can't read.

I admit I move my lips, but why is it that you almost immediately move to personal attacks when challenged?

Never mind, I know why, and don't feel like reading yet another of Swamp's Sanctimonious Soliloquies.

Originally Posted by swamp2

2. Depends on what you are trying to control, there is not one, simple reductionist answer to the question of how does an engine mount for a high torque vehicle differs from that for a low torque vehicle.

Agreed.

Bruce

[Robin_NL]

OFF TOPIC
FWIW the Viper ACR is driven by reknown Dutch international racecar driver Tom Coronel. He'd never driven such a Viper before. He is Klaas Zwart's(Dutch Ascari Sportscar with BMW engines built in the UK founder) son in law.

He kept it in higher revs(limiter) to be 'smoother' than using the immense torque I read somewhere. At only his third lap he set the record.