macfly
February 20th 2007, 16:42
1. Can anyone with a Z8 anticipate a problem with domed struts and/or top frame rail/hood misalignment?
Many reports by Z8 owners have indicated that hitting a bad pothole or similar obstruction under normal driving conditions can cause damage to the front strut towers (doming) and distort the upper frame rails, which in turn can cause a misalignment of the front quarter panels and the hood. These reports have come from numerous owners of both stock and modified cars, including a couple of Alpina owners.
2. Are there parts available from BMW to correct this problem before it occurs?
In the autumn of 2006 BMW AG released a "Performance Package" (PP) which they say will enhance the handling performance of the car over rougher roads – thus the name. However, it is widely accepted that the release of the PP is BMW’s way of giving us a preventative solution without admitting to there being a problem. More info on the PP can be found here (http://www.bmwz8.us/vbb/showthread.php?t=717&referrerid=2).
3. What is the price of the PP and the install?
The PP retails for under $600 and the install will be around $800, with most board members are reporting around $1400 all in.
4. Where can I get the PP and have it installed?
You must order and have it fitted by your BMW dealer, but it is very important to make sure you go to a dealer with Z8 experience, as this thread (http://www.bmwz8.us/vbb/showthread.php?t=740&referrerid=2) shows. Having the kit installed by a service center with little to no Z8 knowledge could result in increased installation costs and possibly an incorrect installation.
5. Is the PP color matched to the car?
No, the PP comes in a black powder coat finish that matches the engine and air box, but some owners have color matched or chromed theirs.
6. Beyond fitting the PP what can I do to minimize the chance of suffering this damage?
BMW NA's official position is that there is a NOT a problem, and thus they will NOT suggest any preventative measures, including the use of the PP. However, the Z8 Club in Europe has suggested that the OE run-flat tires are the key contributer to the damage as they are very heavy and have extremely stiff sidewalls. All the preproduction testing of the Z8 was done using Michelin Pilot Sport tires, the Bridgestone Run Flats were an eleventh hour addition to the car demanded by BMW's Marketing Department, which is almost certainly why the issue didn't surface during the rigorous preproduction testing. Using regular tires both lessens the unsprung weight and the more compliant sidewalls absorb much more of the force that might be transferred to the strut towers in an sudden pothole impact. It is also worth noting that all the owners who opted to fit Dinan castor plates under the front strut towers escaped any damage.
Some owners have opted to install the more complaint Alpina suspension on their Z8's to lessen the possibility of the damage, as only two Alpinas are known to have sustained this damage.
NB: Dana Caldwell at Peter Pan BMW will be offering the full Alpina suspension kit for Z8 owners.
(Personally I had Dana fit the PP and the Alpina suspension kit with 20" BMW Motorsport rims and Pirelli P Zero tires to my car, and am delighted with the result.)
7. How can I tell if a Z8 has this type of damage?
The first frame thread (http://www.bmwz8.us/vbb/showthread.php?t=400&referrerid=2) gives you all the information on the issue, with images of what to look for.
8. What should I do if my Z8 has this type of damage?
The ONLY way to officially confirm damage on a Z8 is to contact BMW Customer Relations (Bill Stuart - 201 263 8210) and schedule an inspection by a Field Service Engineer. This inspection is done at your local BMW Service Center.
9. How difficult or expensive is it to repair this type of damage?
If the shock tower domes are only slightly distorted and there is no pinching of the hood gap lines then fitting the PP should be sufficient, as it will have the effect of sandwiching the the top of the dome, and stabilizing it. If however the shock tower crowns are badly domed, and the upper frame rails are distorted, the car will have to be returned to one of the three BMW Aluminum Repair Centers in the US. They will remove and replace the front half of frame, which involves removing the engine, and disassembling the entire front of the vehicle, which is both a lengthy and expensive process.
BMW NA have suggested to some owners that this should be handled as an accident insurance claim, but BWW NA has also taken appropriate care of regular/repeat customers who are the original owners of the car. This is decided on a case by case basis with BMW NA.
Nov 2008 addendum.
BMW AG is working on a kit to replace domed strut crowns and upper frame rails without doing a full front end frame removal/replacement. Full details and images of this new solution will be posted as soon as we have them.
Many reports by Z8 owners have indicated that hitting a bad pothole or similar obstruction under normal driving conditions can cause damage to the front strut towers (doming) and distort the upper frame rails, which in turn can cause a misalignment of the front quarter panels and the hood. These reports have come from numerous owners of both stock and modified cars, including a couple of Alpina owners.
2. Are there parts available from BMW to correct this problem before it occurs?
In the autumn of 2006 BMW AG released a "Performance Package" (PP) which they say will enhance the handling performance of the car over rougher roads – thus the name. However, it is widely accepted that the release of the PP is BMW’s way of giving us a preventative solution without admitting to there being a problem. More info on the PP can be found here (http://www.bmwz8.us/vbb/showthread.php?t=717&referrerid=2).
3. What is the price of the PP and the install?
The PP retails for under $600 and the install will be around $800, with most board members are reporting around $1400 all in.
4. Where can I get the PP and have it installed?
You must order and have it fitted by your BMW dealer, but it is very important to make sure you go to a dealer with Z8 experience, as this thread (http://www.bmwz8.us/vbb/showthread.php?t=740&referrerid=2) shows. Having the kit installed by a service center with little to no Z8 knowledge could result in increased installation costs and possibly an incorrect installation.
5. Is the PP color matched to the car?
No, the PP comes in a black powder coat finish that matches the engine and air box, but some owners have color matched or chromed theirs.
6. Beyond fitting the PP what can I do to minimize the chance of suffering this damage?
BMW NA's official position is that there is a NOT a problem, and thus they will NOT suggest any preventative measures, including the use of the PP. However, the Z8 Club in Europe has suggested that the OE run-flat tires are the key contributer to the damage as they are very heavy and have extremely stiff sidewalls. All the preproduction testing of the Z8 was done using Michelin Pilot Sport tires, the Bridgestone Run Flats were an eleventh hour addition to the car demanded by BMW's Marketing Department, which is almost certainly why the issue didn't surface during the rigorous preproduction testing. Using regular tires both lessens the unsprung weight and the more compliant sidewalls absorb much more of the force that might be transferred to the strut towers in an sudden pothole impact. It is also worth noting that all the owners who opted to fit Dinan castor plates under the front strut towers escaped any damage.
Some owners have opted to install the more complaint Alpina suspension on their Z8's to lessen the possibility of the damage, as only two Alpinas are known to have sustained this damage.
NB: Dana Caldwell at Peter Pan BMW will be offering the full Alpina suspension kit for Z8 owners.
(Personally I had Dana fit the PP and the Alpina suspension kit with 20" BMW Motorsport rims and Pirelli P Zero tires to my car, and am delighted with the result.)
7. How can I tell if a Z8 has this type of damage?
The first frame thread (http://www.bmwz8.us/vbb/showthread.php?t=400&referrerid=2) gives you all the information on the issue, with images of what to look for.
8. What should I do if my Z8 has this type of damage?
The ONLY way to officially confirm damage on a Z8 is to contact BMW Customer Relations (Bill Stuart - 201 263 8210) and schedule an inspection by a Field Service Engineer. This inspection is done at your local BMW Service Center.
9. How difficult or expensive is it to repair this type of damage?
If the shock tower domes are only slightly distorted and there is no pinching of the hood gap lines then fitting the PP should be sufficient, as it will have the effect of sandwiching the the top of the dome, and stabilizing it. If however the shock tower crowns are badly domed, and the upper frame rails are distorted, the car will have to be returned to one of the three BMW Aluminum Repair Centers in the US. They will remove and replace the front half of frame, which involves removing the engine, and disassembling the entire front of the vehicle, which is both a lengthy and expensive process.
BMW NA have suggested to some owners that this should be handled as an accident insurance claim, but BWW NA has also taken appropriate care of regular/repeat customers who are the original owners of the car. This is decided on a case by case basis with BMW NA.
Nov 2008 addendum.
BMW AG is working on a kit to replace domed strut crowns and upper frame rails without doing a full front end frame removal/replacement. Full details and images of this new solution will be posted as soon as we have them.