strut tower failure
08-14-2016, 06:49 PM
#61
Three Wheelin'
I somehow doubt it, as mild steel has far better elastic properties than cast aluminium, it thus acts as a shock absorber that's capable of absorbing and diffusing the energy throughout the structure.
I'm guessing the GT4 has a spherical bearing (rather than a soft rubber bush) in the strut top mount ? So every last bit of energy put through that strut, would've been transferred straight to the turret, rather than being partially absorbed by the rubber bush fitted to the base/S/GTS models.
In a worst case scenario the bonding of the bush would've failed and the damper rod would've punched through it's pressed steel housing, in the process saving the turret.
Whatever the circumstances, the fractured aluminium turret is a less than perfect end result ....
I'm guessing the GT4 has a spherical bearing (rather than a soft rubber bush) in the strut top mount ? So every last bit of energy put through that strut, would've been transferred straight to the turret, rather than being partially absorbed by the rubber bush fitted to the base/S/GTS models.
In a worst case scenario the bonding of the bush would've failed and the damper rod would've punched through it's pressed steel housing, in the process saving the turret.
Whatever the circumstances, the fractured aluminium turret is a less than perfect end result ....
The preventative solution there was to weld in BMW oem off road reinforcement plates under the strut mounts but I'm not sure that kind solution would work here because those only addressed stretching/tearing of the top mount...
08-14-2016, 07:48 PM
#62
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I'm guessing the GT4 has a spherical bearing (rather than a soft rubber bush) in the strut top mount ? So every last bit of energy put through that strut, would've been transferred straight to the turret, rather than being partially absorbed by the rubber bush fitted to the base/S/GTS models.
EDIT: The GT4, GT3, and Boxster part number for the shock tower itself is also identical: 991 501 477 00.
Best advice is from Spyerx earlier in this thread...DON"T HIT **** !
11-19-2016, 09:09 AM
#69
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Sorry about your car. Thanks.
11-19-2016, 09:32 AM
#70
Joe, sorry that sucks! I saw this 991 at the dealer a while back, same deal. They said he hit a curb. How big was the dip in the road?
If you look at the tub of the GT4 cup car you see they have reinforcement plates at the top of the strut towers . Wonder if they could be retrofitted? To me looks like a design flaw and a way to cut cost. carl
https://rennlist.com/forums/gt4/9158...-your-gt4.html
If you look at the tub of the GT4 cup car you see they have reinforcement plates at the top of the strut towers . Wonder if they could be retrofitted? To me looks like a design flaw and a way to cut cost. carl
https://rennlist.com/forums/gt4/9158...-your-gt4.html
11-19-2016, 12:30 PM
#75
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Wow. Even if you did hit a pothole at freeway speeds, there's no excuse for this failure, IMO. Your wheel should bend and tire blow out before the car suffers major structural failure, and this is major structural failure. I believe you autocross your car, and that puts some higher loads on this part, but this car should be capable of track use and autocross activity without weakening structural components.
Please keep us posted on how Porsche handles this for you. And if you happen back by that dip in the freeway in daylight hours, snap a picture and post it here?
Please keep us posted on how Porsche handles this for you. And if you happen back by that dip in the freeway in daylight hours, snap a picture and post it here?