Z51 Option

[leftyvette]

I was looking at the available unsold 2009 Vettes on Jeff Hardy's website. I noticed that a large percentage are Z51 cars. Is there something about that suspension option that makes them unpopular?

2010 Corvette Locator

 

[dyogi]

I was looking at the available unsold 2009 Vettes on Jeff Hardy's website. I noticed that a large percentage are Z51 cars. Is there something about that suspension option that makes them unpopular?

2010 Corvette Locator

When I was shopping for my car, I was told that the Z51 suspension was a rough ride. Great for the track but not so great for touring if you plan to pleasure drive a lot. I opted for the F55 magnetic suspension which is also used on Ferraris and other high end exotics. Not sure how much difference in ride. I read that the F55 handles better than the Z51, on a track test, the traction control activated with the Z51 and not with the F55. I really don't know which is better, I guess that it would be a personal choice and the arguments would be on both sides of the fence. This is a link to the F55 promo video:

YouTube - Corvette C5 Magnetic Ride -- GM Promotional Video

 

[Hib Halverson]

(snip) I opted for the F55 magnetic suspension which is also used on Ferraris and other high end exotics.(snip)

Note that GM, Delphi and the Lord Corporation developed the "magnetic" suspension used on C5 and C6. At a later date Ferrari and other car companies licensed the technology. GM was first to use it in a production application, introducing it on the 2003 Corvette.

For more information on F55 "magnetic selective ride conrol" or "magna-ride", see: http://www.corvetteactioncenter.com/kb/questions/385/2003%3A+Technical+Article%3A+Magnetic+Ride+

 

[Hib Halverson]

I came back to this thread after thinking about the "Z51 issue" overnight.

Why is it that dealers often discourage Corvette customers from buying Z51?

To consider that we need to know more about Z51, so let's look at some facts. First, Z51, compared to the C6 base suspension, has higher rate springs, higher rate stabilizer bars and shocks capable of more aggressive damping. All those items tend to reduce ride quality. After reading that, many would think the Z51 cars end-up being pretty stiff.

Reality is that Z51s are more stiffly suspended than C6es with base springs and bars, but the ride quality, in practice, while not as nice as a base car, is not as uncomfortable as were the Z51s of the C5 era.

On general difference between C5 and C6 which impacts ride quality is that the suspension geometry was revised for 2005 to increase travel. This allowed GM to keep the high rate Z51 springs and bars but go to shock valving that wasn't quite as stiff as was Z51 for C5. The end result was ride quality somewhere between that of base and Z51 on C5.

The statement was made above that cars with F55 "Magnetic Selective Ride Control" (also known to some as "magna-ride" or just "MR") and Z51 handle about the same. Well...that's kinda sorta true but mostly false. First, understand that F55 is not really a "suspension" it's just a set of shock absorbers which can change their valving in near real time. For more information on MR and how it works see the article at the URL listed in the post above.

How close Z51 and MR cars are in handing depends on how they are being driven. Let's say you like to take curved freeway/expressway on/off ramps and transitions at a speed that's a little more fun than what's posted or let's say you like to go on drives with your club through the mountains "caravaning" with the group at "sporting" speeds but not really fast. If that's the case then, to you, C5es with Z51 or F55 will have a similar feel in the turns but the car with F55 will will ride nicer.

On the other hand, let's say you like to take those curved freeway ramps and transitions at twice the posted entry speeds or, when you're on a mountain run with your club, you are one of the couple of people who move to the front and "run-away-and-hide" from the rest of those touring folks. If that's the case, a Z51 will handle better and be easier to drive at the limit than will the car with base springs, bars and MR shocks. As for ride, well...you probably don't care that much, but believe it or not, when run hard near the limit, the ride qualities of the Z51 and the F55 will be closer.

Now, let's say in addition to carving up freeway ramps and mountain roads you like to take your car to an autocross or even a "track day" event. If that's the case, don't consider F55. You need Z51 for not only it's increased roll stffness but also it's better Goodyear F1 Supercar EMT tires, close ratio transmission, engine oil, trans and power steering coolers, better brakes and, in the case of automatics, shorter gears.

Why do some dealers try to convince potential customers to avoid Z51? One reason might be that amongst dealers, especially those unfamiliar with the specifics of Corvette suspensions (which means the majority of them), Z51 has a stigma of rough ride attached to it that goes clear back to the C4 years. To those dealers, I say, "Yeah, C6 Z51 is damped more aggressively than the base cars, but the ride is not near as harsh as was Z51 or Z07 in the C4 era."

Other dealers aggressively promote Magna-Ride because they make more money selling that option then they do selling Z51. In model year 2009 the MSRP difference was about 300 bucks.

There may be an arrogance upon the part of some dealers, ie: "We know better than you what you want." Combine that with a misquided belief that most Corvette buyers today are fat-bottomed old boomers who want an LS3's power, loud exhaust, have no interest in a Vette's handling and want a car which rides like a Cadillac and you have dealers pointing people at base suspensions and F55. Actually...weren't those the folks who were supposed to buy Cadillac XLRs?

There's still another group of dealers will steer customers away from Z51 because a customer with F55 is less likely to complain about the car not handing to their liking when driven at the limit than a customer with Z51 is likely to complain about harsh ride and some dealers loath customer complaints so much they choose to err on the safe side...even if the customer expresses a desire to order Z51.

In 'MY08, the last year for which Mike Antonick's well-respected Black Book published numbers, Z51s outsold F55 by more than 2 to 1. Also, on average, since MY05 C6 Z51 has outsold F55 by about 2 to 1. That is the reverse of the last two years of C5 when MR was available. In MY03/04 F55 outsold Z51 by by more than 3 to 1. What caused that stunning reversal? I have no hard fact, but I suspect much of why the big swing in Z51's numbers relates to the better ride of C6 Z51 compared to C5 with the same option.

In summary, yeah, the Z51's ride is more stiff but not near as stiff as many dealers think.

 

[leftyvette]

Hib, thanks for the detailed thoughts! I still have to wonder: why are those dealers ordering Z51 Vettes for their inventory if they feel any negative attitudes concerning that option?

Again, your points have helped me get my thoughts straight concerning which may be best for me. I still like the idea of the Z51 option and will just have to drive one to see what my initial impression will be!

 

[JBsC5]

I think a lot of the guys who like the idea of the Z51 decided that instead of buying a leftover z51 they would go for the slightly more expensive but even better packaged Grand Sport.. (I believe right now I could buy a grand sport for 51 grand minus 3 grand in bonus points) 49 net which is a smoking deal. Im half tempted to sell my perfect 2008 Z51 ilt NPP exhaust for 34 grand privately and buying a new RED Grand sport!)

I know if I were in the market for a new vette during the last part of 2009? I'd wait...and gladly pay more for the 2010 grand sport model. (wide body fenders, wider wheels and tires, dry sump oiling system, launch control) I'd say thats worth the extra few dollars over an 09 Z51.

Just my opinion but thats why I think there are more leftover 2009's with the Z51 suspension.

Hibs right on target..I'm just adding some possible insight as to why their are more Z51 suspension corvettes left over..

I have the Z51 suspension on my 08 and its great. Much more refined than my 1999 C5 Z51 or my c5 zo6.

Buy with confidence.

 

[Hib Halverson]

Do we know if the pool of leftover Z51s were, in actuality, all ordered by dealers or were they cars built by GM which dealers were asked to take?

I'm not sure whether I agree that the new Grand Sport is "better packaged". Uh...I guess it depends on what "better packaged" means. I think it's meaning is a bit subjective.

 

[JBsC5]

Do we know if the pool of leftover Z51s were, in actuality, all ordered by dealers or were they cars built by GM which dealers were asked to take?

I'm not sure whether I agree that the new Grand Sport is "better packaged". Uh...I guess it depends on what "better packaged" means. I think it's meaning is a bit subjective.

Yes your absolutely right.. still as an owner of an 08 z51 had I known that a few months later a wide body wider wheels,wider tires, dry sump oiling system and a launch control ..I would have waited and gladly had paid the extra 5 grand it would have cost me...

Of course the 2009's were the ones that had only a few months ...

How many of the guys who bought base corvettes or Z51 corvettes have spent upwards of 10 grand to just get the wide body look retrofitted on thier corvettes..

5 grand for the wide body as well as all the performance items..? dry sump oiling system, Z06 brakes, wider wheels and tires, and launch control..

The motor is hand built too..

Its a personal choice as you mentioned..


I would also like to say to the original poster here...as I drove the 2 or 3 hours home in my new o8 Z51...I kept saying to myself on my ride home...I just bought an awesome new luxury car....(and thats with the Z51 suspension)

Hibs right..the C6 is really quite an evolution in design from the C5 Z51.. and I liked that car too. The NVH is much improved on the C6 z51...

If you decide to get one..you'll be very happy. I know I am and the car is amazing. If it were me though...I'd go for the 2010 Grand Sport m6 1lt for 49 grand plus tax!

I can't help it..I find the wide body of the grand sport sexy as hell...and launch control would be fun too.. (I dig the technology) I could have lived without the z06 brakes and the dry sump oiling systems a 50 50 for me...but I'm sure it would be cool to have....

HTH

 

[napacruzerC5]

I added a C6 Z51 front sway bar to my F45 C5 and was very happy with the results especially on an autocross course. I also have a C6 F55 and wonder if adding the C6 Z51 sway bars would also be a beneficial mod (better handling).

 

[Hib Halverson]

Just a Z51 bar on a base car with nothing else would have made for increased understeer...not what you want, if you're really autocrossing hard but, indeed, it would reduce body roll by increasing front roll stiffness.

The problem comes with no increase in rear bar size to match the bigger one in front. Add roll stiffness up front without an increase in rear roll stiffness generally makes the car too tight.

On the other hand, adding C6 Z51 bars to a base C6 or one with F55 will increase roll stiffness on both ends and may make a modest improvement in at-limit handling.

 

[napacruzerC5]

Just a Z51 bar on a base car with nothing else would have made for increased understeer...not what you want, if you're really autocrossing hard but, indeed, it would reduce body roll by increasing front roll stiffness.

The problem comes with no increase in rear bar size to match the bigger one in front. Add roll stiffness up front without an increase in rear roll stiffness generally makes the car too tight.

On the other hand, adding C6 Z51 bars to a base C6 or one with F55 will increase roll stiffness on both ends and may make a modest improvement in at-limit handling.

Yes it did add front stiffness and promoted understeer but also took away a greater propensity for oversteer. I don't know if the combination of mods: lowered on stock bolts, non-R rated Kumho MXs on stock C5 wheels plus the fatter front sway bar just made it "feel" better all the way around but it felt better in the corners. I also understand that understeer also feels "safer" than oversteer to most drivers.

Apologies to OP for hijacking your thread.

 

[Hib Halverson]

How did the change affect your times?

 

[napacruzerC5]

How did the change affect your times?

A lot closer to the Hoosier shod C5's in my group...or was it the shorter, faster courses :eyerole

 

[tim414]

I was looking at the available unsold 2009 Vettes on Jeff Hardy's website. I noticed that a large percentage are Z51 cars. Is there something about that suspension option that makes them unpopular?

2010 Corvette Locator

I don't think Z51 is rough at all. I think it's mainly personal preference. For me it came down to simple numbers. I've wanted a Vette most of my life. At age 48 I finally bought my first one and very proud of it. My plans were to initially make my last payment on my Yukon and then buy a 2010 Gran Sport. The GS came available at same time I paid off Yukon. (did not want two payments at same time, also wanting to keep Yukon as second vehicle). But, given the economy and having taken such a BIG hit on my retirement savings it suddenly made financial sense to get the '09 cause I got such a great deal on it. Not only that, before I knew of the GS coming available my dream car was the (Atomic Orange Z51 roadster w/beige top and cashmere interior) C6 Z51 roadster. It just so happened I had been watching this very car (my dream car) in Burleson, Texas 120 mi away). I was hoping that it would be around (this was early '09) by the end of summer when I paid off my Yukon. Then I find out GS will be coming for 2010. Long story short, it cost me 10k less to have my dream car in its orginal form. Yes, I wanted the wider fenders, (that mean look) etc, but after reading articles and studying specs etc for the previous two years, the differences were not really that great. Dry sump, wider fenders and tires are basically the diff. Z51 is standard equipment on GS. F55 is only shocks as one of the threads stated. To me, the real meat and taters is Z51. The substance of Z51 verses the F55 is really not measurable in my book. I had a freiend who bought new '04 Z51. Yep, the ride is a little bit stiffer. The guy who posted the earlier thread is right on concerning Z51 vs the F55. Too bad that base Vette buyers after MY09 will not get the option. To get the meat/taters they will have to spend 10k over the base. But yes, I would have loved to get the GS, the look is awesome. But the economy affected my wallet so much I personally thought it was right (financially) for me to stay with my orginal dream car and VERY proud to have it.

 

[darkstar]

I don't think Z51 is rough at all. I think it's mainly personal preference. For me it came down to simple numbers. I've wanted a Vette most of my life. At age 48 I finally bought my first one and very proud of it. My plans were to initially make my last payment on my Yukon and then buy a 2010 Gran Sport. The GS came available at same time I paid off Yukon. (did not want two payments at same time, also wanting to keep Yukon as second vehicle). But, given the economy and having taken such a BIG hit on my retirement savings it suddenly made financial sense to get the '09 cause I got such a great deal on it. Not only that, before I knew of the GS coming available my dream car was the (Atomic Orange Z51 roadster w/beige top and cashmere interior) C6 Z51 roadster. It just so happened I had been watching this very car (my dream car) in Burleson, Texas 120 mi away). I was hoping that it would be around (this was early '09) by the end of summer when I paid off my Yukon. Then I find out GS will be coming for 2010. Long story short, it cost me 10k less to have my dream car in its orginal form. Yes, I wanted the wider fenders, (that mean look) etc, but after reading articles and studying specs etc for the previous two years, the differences were not really that great. Dry sump, wider fenders and tires are basically the diff. Z51 is standard equipment on GS. F55 is only shocks as one of the threads stated. To me, the real meat and taters is Z51. The substance of Z51 verses the F55 is really not measurable in my book. I had a freiend who bought new '04 Z51. Yep, the ride is a little bit stiffer. The guy who posted the earlier thread is right on concerning Z51 vs the F55. Too bad that base Vette buyers after MY09 will not get the option. To get the meat/taters they will have to spend 10k over the base. But yes, I would have loved to get the GS, the look is awesome. But the economy affected my wallet so much I personally thought it was right (financially) for me to stay with my orginal dream car and VERY proud to have it.

Congrats on your choice of colors on that original dream car. At the time I purchased my coupe I had long wanted the vert as you got but financially could not. Enjoy the Z-51's flat cornering, it's great!

 

[tim414]

Congrats on your choice of colors on that original dream car. At the time I purchased my coupe I had long wanted the vert as you got but financially could not. Enjoy the Z-51's flat cornering, it's great!

Cool ride. I have one just like yours. What interior color is yours? Yep, I like driving it. Especially accelerating out of corners....thats a blast....although I did get smoked by a MUSTANG this last weekend. Had a turbo and Nitro....589 hp....blew my Vette away.....

 

[darkstar]

Cool ride. I have one just like yours. What interior color is yours? Yep, I like driving it. Especially accelerating out of corners....thats a blast....although I did get smoked by a MUSTANG this last weekend. Had a turbo and Nitro....589 hp....blew my Vette away.....

The interior is cashmere. Ran a Shelby 500 about 3 miles. It was give in the beginning, but caught up in 3rd and then we blew it off. I want to believe I would have took'em but what the hey. Did get tromped by some type of BMW though.

 

[tim414]

The interior is cashmere. Ran a Shelby 500 about 3 miles. It was give in the beginning, but caught up in 3rd and then we blew it off. I want to believe I would have took'em but what the hey. Did get tromped by some type of BMW though.

Mine has cashmere interior and beige top. I was looking at Bowling Green Plant statistics and found there were only 91 (2009) Atomic Orange Verts built. When colors AND Z51 are considered there was approx 33 or less like it (my math, I could be wrong). I was greatly surprised, cause I was thinking the number would be closer to '08 numbers.

If I remember correctly your '08 is somewhat rare (color/Z51). I think it was around (2008) 38.7% of coupes had Z51 and 6.4% of all coupes were Atomic Orange MY'08....(1272 coupes)....so doing the math close to 39% of MY'08 coupes had Z51 pkg and 6.4% were Atomic Orange, if my math is correct there are approx. 470 Vettes like yours MY'08.....I guess we are part of the minority :confused that like Atomic Orange Metallic (83U). I would have thought Atomic Orange would have been a more popular color. :confused Oranges/yellows/reds/blues always cool colors for sports cars. You probally already know this info. (in case you didn't it's listed on the BG Assembly Plant Website).
Anyway, I suppose you and I know what's cool!!!

 

[darkstar]

Mine has cashmere interior and beige top. I was looking at Bowling Green Plant statistics and found there were only 91 (2009) Atomic Orange Verts built. When colors AND Z51 are considered there was approx 33 or less like it (my math, I could be wrong). I was greatly surprised, cause I was thinking the number would be closer to '08 numbers.

If I remember correctly your '08 is somewhat rare (color/Z51). I think it was around (2008) 38.7% of coupes had Z51 and 6.4% of all coupes were Atomic Orange MY'08....(1272 coupes)....so doing the math close to 39% of MY'08 coupes had Z51 pkg and 6.4% were Atomic Orange, if my math is correct there are approx. 470 Vettes like yours MY'08.....I guess we are part of the minority :confused that like Atomic Orange Metallic (83U). I would have thought Atomic Orange would have been a more popular color. :confused Oranges/yellows/reds/blues always cool colors for sports cars. You probally already know this info. (in case you didn't it's listed on the BG Assembly Plant Website).
Anyway, I suppose you and I know what's cool!!!

Thanks for the facts and figures. I was not aware of the uniqueness of our color option. I was equally surprized that there were not more 83U Vettes on the road.