G8 GXP review - wheelhop?

[fastball]

Originally Posted by fbodfather

Important to understand that the G8 is not the same as the Camaro.

G8 is, for lack of a better term, "Zeta 1" -- and the Camaro is "Zeta 2" -- many more improvements.

Thank you. Now, could you take this information to the other thread that people fear the Camaro SS will be subject to awfull fuel ecomony numbers and a gas guzzler tax just because the G8 GXP is?

[DGthe3]

Originally Posted by rayhawk

Ok, I am doing a bit of speculation here, but as I understand it axle hop is due to resonance in the system. That is why it shows up more pronounced at a particular rpm. Obviously, it is a complex system that involves rotating tires, flexibility in the suspension and the car, etc. It is not quite as simple as a resonant frequency of a string, as there are many degrees of freedom to a car's suspension. However, with that said, it appears the reason for the different size shafts is intended to shift or minimize the natural resonant frequency of the suspension as a whole without adding excessive mass to the structure. Two different diameter shafts will have a different resonant frequency, so even if on their own they would be prone to some inherent vibration, the fact that they "ring" at a different freq. means they no longer combine to magnify the problem into noticeable or damaging wheel hop.

To the best of my knowledge, thats how it works in the CTS-V and ZR1, as well as the Camaro

[blackZbandit]

It's basically like hat myth about soldiers marching across the bridge. The soldiers marching wound up matching the frequency of the bridge's natural resonance which amplified it and caused it to collapse. This was tested on mythbusters and though they couldn't prove it, due to the results of their small-scale tests they did call it plausible. We can also take Nikolai Tesla's earthquake machine which was designed to collapse buildings but machting and amplifying their natural resonance frequency, which they also tested and found to be plausible. Now apply this same principle to a much smaller "structure" like a rear-suspension setup and you can see where it can cause havoc. If the resonance frequency between the 2 axles are not consistent it is much more difficult for one to affect the other resulting in reduced chances of wheel hop.

I'm sure it's much more complicated than that, but that's my take on the basic principle behind the wheel-hop solution.

[LSxJunkie]

Originally Posted by Robert91RS

And here we go again. First let me say Fbodfather assured us all that wheel hop will not be a problem-END OF STORY! Maybe the GXP wont get the mods or maybe they tested a pre-pro that didnt have them yet. And sports car or not is arguable and has been discussed many times in the apropriate threads, please go there. Thanks and much love for our GT500 friend, I'm not targeting you here.

Just because someone says "it's not going to be a problem" doesn't mean it's not going to be a problem. Sorry, but that's life. It was supposedly guaranteed not to be a problem on the ZR1 too, but..... see below.

Originally Posted by SoFlaZ

Does the G8 have the unequal diameter axle shafts? It might not but I know the Camaro will like the ZR1 to help eliminate the hop.

Originally Posted by gtahvit

^That ought to answer that question.

I believe the technical term is "asymmetric half shafts." But yes, basically one, is bigger and heavier than the other. Which eleiminates the wheel hop.

Reduces.

Originally Posted by DGthe3

To the best of my knowledge, thats how it works in the CTS-V and ZR1, as well as the Camaro

Lotta spuculation in here. The unequal half shafts don't eliminate wheel hop, they reduce it. I was at Englishtown yesterday watching a ZR1 hop through the 60' and on the 1-2. The new -V will hop too. It may be reduced, but don't think that staggered diameter axles is the magic wand that eliminates the hop. It doesnt. Hop is part of the nature of an IRS. You folks should probably stop holding the ZR1 up as an example because, well, it hops.

[UCF w00t]

Originally Posted by LSxJunkie

You folks should probably stop holding the ZR1 up as an example because, well, it hops.

I just re-watched the clip from Top Gear of Jeremy laying down some rubber with the ZR1 and well, it didn't hop.

[nonsensez9]

Originally Posted by garagelogic

Gotta love those superior, high-tech, IRS setups. Most likely, you will have to make some post-purchase modification to get rid of wheel-hop on the Camaro. I did with my GTO. The geometery is just not ideal for straightline performance.

my '05 Mustang GT had crazy wheel hop until I replaced the upper control arm with one that had stiffer bushings. Hop is cured, but there's a touch more NVH. Anything is possible and everything is a compromise.

[radz28]

Originally Posted by nonsensez9

my '05 Mustang GT had crazy wheel hop until I replaced the upper control arm with one that had stiffer bushings. Hop is cured, but there's a touch more NVH. Anything is possible and everything is a compromise.

[1_2Many]

Originally Posted by garagelogic

The geometery is just not ideal for straightline performance.

Thanks expert. Very insightful

Tell us more about the "geometery" will you? I'm dieing to hear this.

And while your at it please explain why I had axle hop on my solid axle 1991 Firebird Formula?

[garagelogic]

Originally Posted by 1_2Many

Thanks expert. Very insightful

Tell us more about the "geometery" will you? I'm dieing to hear this.

And while your at it please explain why I had axle hop on my solid axle 1991 Firebird Formula?

I'm not sure why there is so much venom in your post, but I think you (and others) have taken my first post to be some sort of cut on the new Camaro, which was never the case.

My comments were directed at the shortcomings of an IRS setup at the dragstrip, in stock form, on anything other than pure performance vehicles. Yes, there are vehciles with IRS that perform extremely well at a dragstrip, but almost all of them that do have a suspension under them that is more performance-oriented. Can you solve wheel-hop in an IRS car, sure, I did it with my GTO. It's more a matter of will the vehicle come from the factory with those solutions already in place. My guess is that they will not, and here is why I say that.

Like any other mass produced car, you have to figure the new Camaro is going to be delivered with a setup that is a compromise on many levels. Remember, while one person might want their Camaro to have great cornering, the next guy might want great straightline performance, and the next guy/gal might want a smooth ride. One type of suspension bushing might eliminate wheel-hop altogether, but might result in NVH that is no acceptable to the everyday driver. Likewise the type of shocks and the valving in those items.

See, as far as GM is concerned (or Ford, or Dodge for that matter) the car has to be a jack of all trades and master of none, which is why I believe there will be wheel-hop on as-delivered-from-the-factory Camaros despite what others might suggest. Heck, my GT500 had wheel-hop when I bought it for these exact same reasons. Likely that was why your Formula had it as well.

I am by no means an expert in this area at all, but I am still entitled to have my opinion and will do so until those opinions are proven to be incorrect. I, for one, hope they are, because I would prefer not to have the same issues with my new Camaro and wheep-hop as I did with my GTO or GT500.

[Mr. Wyndham]

Originally Posted by garagelogic

It's more a matter of will the vehicle come from the factory with ose solutions already in place. My guess is that they will not, and here is why I say that.

Like any other mass produced car, you have to figure the new Camaro is going to be delivered with a setup that is a compromise on many levels....

...See, as far as GM is concerned (or Ford, or Dodge for that matter) the car has to be a jack of all trades and master of none, which is why I believe there will be wheel-hop on as-delivered-from-the-factory Camaros despite what others might suggest.

I hear it's your opinion and all that jazz...but I have to comment:

#1; you really should put more stock in what the engineers who worked on this car have to say, and
#2; You're really gonna want to test-drive this car. I have this funny feeling you're going to be one of the uber-impressed people.

[garagelogic]

Originally Posted by Dragoneye

I hear it's your opinion and all that jazz...but I have to comment:

#1; you really should put more stock in what the engineers who worked on this car have to say, and
#2; You're really gonna want to test-drive this car. I have this funny feeling you're going to be one of the uber-impressed people.

Look I appreciate all of the information that has been shared by people who might be in the know about the new Camaro. However, I also know that those same people are GM employees working on a car that has not even been released yet and who are looking for the Camaro to be a GM halo car. Do you really think they would say anything that might tarnish that perception in the maketplace or give people pause about purchasing one?

I will be driving one and I have no doubt I will be impressed. I was wary about the GTO before I bought it and I was pleasantly surprised about how well rounded it was as a vehicle. Likewise, I heard a lot of negative things about the GT500, but it, too, has impressed me.

[Mr. Wyndham]

Originally Posted by garagelogic

Look I appreciate all of the informaiton that has been shared by people who might be in the know about the new Camaro. However, I also know that those same people are GM employees working on a car that has not even been released yet and who are looking for the Camaro to be a GM halo car. Do you really think they would say anything that might tarnish that perception in the maketplace or give people pause about purchasing one?

By that same token...these people are rather..."high profile", should I say? After all, there aren't many people confirmed to be "in the know" that share information like this with such certainty. If they're just sugar coating everything and puffing the car to be bigger than it is...don't you think that might hurt their reputation...A LOT when the car comes fizzling down to earth? They want that less than they want super Camaro rumors...

This solution to wheel-hop technique is relatively new to GM, and they have it employed on very few vehicles to date, afaik. The ZR1, the CTS-V, and now the Camaro. It's lived up to all the hype on the first two, so I suspect it will live up to the hype on the Camaro.

[garagelogic]

Originally Posted by Dragoneye

By that same token...these people are rather..."high profile", should I say? After all, there aren't many people confirmed to be "in the know" that share information like this with such certainty. If they're just sugar coating everything and puffing the car to be bigger than it is...don't you think that might hurt their reputation...A LOT when the car comes fizzling down to earth? They want that less than they want super Camaro rumors...

This solution to wheel-hop technique is relatively new to GM, and they have it employed on very few vehicles to date, afaik. The ZR1, the CTS-V, and now the Camaro. It's lived up to all the hype on the first two, so I suspect it will live up to the hype on the Camaro.

It's not so much what they say, it's what they don't say. Like I said before, I'll reserve judgement until I acually experience the car myself rather than just take someone else's word for it. I've been known to be wrong many, many times before.

[LSxJunkie]

Originally Posted by UCF w00t

I just re-watched the clip from Top Gear of Jeremy laying down some rubber with the ZR1 and well, it didn't hop.

Woohoo. Neither did my GTO when I revved her up to 4-5 grand and dumped the clutch, which is what Clarkson did. My car didn't hop in the burnout box or when I powerbraked it either. It hopped when I tried to launch the car and on a hard shift, which is exactly what I saw out of the ZR1.


Trust me, the ZR1 will still hop if you try to launch it on stock tires. I know because I've seen it.