Bad shocks - What would you do?
07-18-2006, 06:30 AM
#46
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I spoke to the guy who had the shcok problem. He has a business working on 928 only, so he knows his stuff.
He fitted Bilsteins to the rear of his car. He imdediately had problems with the back of the car hopping (tramping) under hard acceleration. He removed the shocks and worked the pistons over their full range a dozen times or so. That solved the problem. His theory was that some air had been trapped. Maybe due to them being stored for a longtime on their side.
Slightly different to your issue Bill, as his car seemed OK if you bounced the car on its suspension.... but still may be relevant
He fitted Bilsteins to the rear of his car. He imdediately had problems with the back of the car hopping (tramping) under hard acceleration. He removed the shocks and worked the pistons over their full range a dozen times or so. That solved the problem. His theory was that some air had been trapped. Maybe due to them being stored for a longtime on their side.
Slightly different to your issue Bill, as his car seemed OK if you bounced the car on its suspension.... but still may be relevant
07-18-2006, 11:49 AM
#47
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Bill,
Glad you made it home safely, Cheryl agreed with your decision when she rode with you. To set the record straight, I do have Koni's on the GTS and they do have "specials valving" whatever that is. They are far different (more control) than yours but I also never liked them. They have a sharp hit on compression and do not control the car properly at 160-170 mph. The car always wallowed slightly in high speed sweepers and I could not get rid of it. I always blamed it on lack of rebound damping. The GTS has stock springs so it shouldn't be real difficult to control rebound. I also vote to get the shocks fixed or new on warranty, but invest in some new coil overs.
As an update on the race, Team Porsche won the Team Challenge. Unfortunately the 928 contingincy didn't help the effort. I was disqualified for breaking tech
( we would have been 2nd) , George had boost problems and couldn't maintain speed, you of course had to withdraw. I can't remember how Pete Whelan did in his S/C 88.
Man I got to tell you the 155 mph class with a tech of 168 is tough not to break tech. 13 mph has you running 160 - 165 mph in most of the corners just to catch up to target. We will try harder next time.
If you don't like the new Koni's, I vote for the Penske's. They are awesome.
Glad you made it home safely, Cheryl agreed with your decision when she rode with you. To set the record straight, I do have Koni's on the GTS and they do have "specials valving" whatever that is. They are far different (more control) than yours but I also never liked them. They have a sharp hit on compression and do not control the car properly at 160-170 mph. The car always wallowed slightly in high speed sweepers and I could not get rid of it. I always blamed it on lack of rebound damping. The GTS has stock springs so it shouldn't be real difficult to control rebound. I also vote to get the shocks fixed or new on warranty, but invest in some new coil overs.
As an update on the race, Team Porsche won the Team Challenge. Unfortunately the 928 contingincy didn't help the effort. I was disqualified for breaking tech
( we would have been 2nd) , George had boost problems and couldn't maintain speed, you of course had to withdraw. I can't remember how Pete Whelan did in his S/C 88.Man I got to tell you the 155 mph class with a tech of 168 is tough not to break tech. 13 mph has you running 160 - 165 mph in most of the corners just to catch up to target. We will try harder next time.
If you don't like the new Koni's, I vote for the Penske's. They are awesome.
07-18-2006, 01:14 PM
#48
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Tim:
George filled me in on the results. Not exceeding 168 while trying to average 155 is almost ridiculous, as you found out.
Your feedback on the Konis is not reassuring. Although I never liked them from Day One, their behavior in open road racing was not undriveably bad until this weekend. I don't plan to go over 150/168, and found them OK in that speed class. I could tell they weren't great, but I could drive with them by limiting turn speed to prevent wallowing.
If the new Konis can't handle the twisties on my test route the way my original Boge sport shocks could, they will go on eBay and I will be looking at the coilover options more closely. Koni tech seemed very interested in my input. Perhaps I will try to work with them on some new valving, but I doubt it.
George filled me in on the results. Not exceeding 168 while trying to average 155 is almost ridiculous, as you found out.
Your feedback on the Konis is not reassuring. Although I never liked them from Day One, their behavior in open road racing was not undriveably bad until this weekend. I don't plan to go over 150/168, and found them OK in that speed class. I could tell they weren't great, but I could drive with them by limiting turn speed to prevent wallowing.
If the new Konis can't handle the twisties on my test route the way my original Boge sport shocks could, they will go on eBay and I will be looking at the coilover options more closely. Koni tech seemed very interested in my input. Perhaps I will try to work with them on some new valving, but I doubt it.
07-18-2006, 01:24 PM
#49
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I'll keep my fingers crossed for the Koni's.
If all else fails I have located a set (4) of single adjustable Penske's. Just need to change the shock mounts. Totally re-valvable by the user. Currently set up for a 928. A lot less than what we talked about in Wendover.
If all else fails I have located a set (4) of single adjustable Penske's. Just need to change the shock mounts. Totally re-valvable by the user. Currently set up for a 928. A lot less than what we talked about in Wendover.
07-18-2006, 01:37 PM
#50
Drifting
And I missed all the fun...
My bilstein's with Weltmiester fronts and stock front springs on the rear would tend to launch a bit over bumps but there was no wallowing in high speed corners in fact, I could do a beautiful four wheel drift at over 130mph with that setup. Stock swaybars were all I used then. Hitting bumps in the corners would make the car step out a bit but no wallowing.
We do have external Koni's with Hypercoils on the GT but I haven't driven it into corners at those speeds...yet...
My bilstein's with Weltmiester fronts and stock front springs on the rear would tend to launch a bit over bumps but there was no wallowing in high speed corners in fact, I could do a beautiful four wheel drift at over 130mph with that setup. Stock swaybars were all I used then. Hitting bumps in the corners would make the car step out a bit but no wallowing.
We do have external Koni's with Hypercoils on the GT but I haven't driven it into corners at those speeds...yet...
07-18-2006, 01:46 PM
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Originally Posted by Tahoe Shark
I'll keep my fingers crossed for the Koni's.
If all else fails I have located a set (4) of single adjustable Penske's. Just need to change the shock mounts. Totally re-valvable by the user. Currently set up for a 928. A lot less than what we talked about in Wendover.
If all else fails I have located a set (4) of single adjustable Penske's. Just need to change the shock mounts. Totally re-valvable by the user. Currently set up for a 928. A lot less than what we talked about in Wendover.
07-18-2006, 04:08 PM
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Bill,
I'd go with the consensus - replace under warranty. I have the Bilstein/Eibach setup and am fairly happy but it can be a bit harsh on our bad roads up here. I've yet to track it and that will have a big influence on my final opinion.
I'd go with the consensus - replace under warranty. I have the Bilstein/Eibach setup and am fairly happy but it can be a bit harsh on our bad roads up here. I've yet to track it and that will have a big influence on my final opinion.
07-18-2006, 04:13 PM
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Flott:
Thanks for the vote. The replacement Konis are on the way and I will install them and test before I do anything further.
Thanks for the vote. The replacement Konis are on the way and I will install them and test before I do anything further.
07-20-2006, 03:54 PM
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I sent the info to Koni on the 18th and they sent out the replacements on the same day via UPS. Man, that is fast service. Should have them any day.
07-20-2006, 04:02 PM
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Originally Posted by Bill Ball
I sent the info to Koni on the 18th and they sent out the replacements on the same day via UPS. Man, that is fast service. Should have them any day.
I have a complete new suspension that I am installing this weekend, or next,(Koni/Eibach, 928SP front and rear sway bars) and it's good to know they are proactive in taking care of any problems.
07-20-2006, 04:21 PM
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When I called to make sure they had gotten my info by fax, you'd have thought I just placed a large group buy order. They were pleasant, upbeat and gave me a tracking number without asking. I hope the shocks pleasantly surprise me as well. Same for you, Jim.
07-20-2006, 04:26 PM
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I am sure they will. And thanks! 
[QUOTE=Bill Ball]When I called to make sure they had gotten my info by fax, you'd have thought I just placed a large group buy order. They were pleasant, upbeat and gave me a tracking number without asking. I hope the shocks pleasantly surprise me as well. Same for you, Jim.[/QUOTE]
[QUOTE=Bill Ball]When I called to make sure they had gotten my info by fax, you'd have thought I just placed a large group buy order. They were pleasant, upbeat and gave me a tracking number without asking. I hope the shocks pleasantly surprise me as well. Same for you, Jim.[/QUOTE]