svp928

Bill, my offer still stands- my Bilsteins/Eibachs are 7 yrs old, and still work great for track or street.

Steve

Bill Ball

fredis: My springs are stock 2 stripe sport springs. I thought they were OK before I switched from the original red Boge gas sport shocks to the Konis. There was a major change in handling imemdiately after the Konis were substituted for the old sport shocks. The car bottomed over bumps that previously did not disturb it and didn't corner near as level. I do have new Eibach springs ready to go in and was counting on the combination, which you indicate is fine. I'm just not sure about the behavior of the new shocks. It may mean nothing, as Heinrich suggests. A shock dyno test would answer that.

Bill DeM: If I cannot get comfortable with the Koni behavior in my garage floor testing, I may just order up the Bilsteins and put them in with the Eibachs. It's real hard to decide as I see occasional complaints that the Bilsteins are too soft as well. Any of the shocks can be revalved stiffer. Based on driving George Suennen's Koni/stock spring setup, I shouldn't have to.

I suppose for the sake of science, I should just set these Konis, ignoring the garage floor rebound behavior, install them and see what they feel like. I can test the twisty behavior locally but not the super high speed stability.

Steve: thanks again for the driving test offer. Other cars seem fine with Konis, so I'm not sure if driving another car is going to help, unless you want to sell me the whole car.

pmotts: Go ahead and install them. Others are happy with Konis, a few are not.

Bill Ball

I'm open to any suggestions. Heinrich is exaggerating my knowledge, particularly when it comes to suspension. I just know what I have had for the past 3 years is bad. Carl sells the same Konis and a package with Hypercoil springs, as well as Bilsteins.

IcemanG17

Bill
Thats sucks....but might as well install them and see how it feels.....it has to be better than before....??

Bill Ball

I just want someone who knows to tell me the free extension time means NOTHING, even though it CLEARLY responds to the rebound adjuster, as I showed. The Koni tech guy was unsure, hemmed and hawed and said I needed to dyno them. A shock dyno test would confirm whether the shocks are matched or not, but sending them back and forth to Koni is the only option I have to do that.....or maybe not...
http://www.circletrack.com/howto/82884/

T_MaX

Bill, that unit will work if you build it to spec and follow directions! I helped a freind make one and there are about three groups of local racers who share it now in the winter to check what shocks degraded and the amount. What sucks about the 928 is that it takes so long to get a shock off the car. On our race cars it takes longer to get the tools out than to get the shock off

What would be nice is if some one would come up with shock mounts for the 928 so that a person could use any off the shelf race shock (heim ended).


Here are some others!

http://www.shockdyno.com/

http://www.roehrigengineering.com/2vs_shock_dyno.htm

Spring checker
http://www.intercomp-scales.com/detail.cfm?ItemID=627

Is sure seems as though manufacturing quality has gone down hill! Almost everyday I hear stories of new parts (Factory/OEM/Remanufactured) being defective out of the box!

Bill, if you can’t get repeatable results out of the box, send them back!

sublimate

I don't KNOW, but I suspect the free extension time doesn't mean much. It's like measuring the speed of a car from 0-1 mph (I bet my pickup in 4x4-Lo could beat most of the cars here).

Yes, the rebound adjuster affects the free extension time (it's changing the size of the orifice the fluid has to squeeze thru), and yes, they should be about the same. But, particularly in a new shock, if there's a small air bubble or some heavy greese from assembly near the orifice then the free extension time would be greatly affected - but under any real load it'd be blown right thru.

You could probably fashion your own shock dyno if you have a weight machine...

Jim R.

Bill,

If they are not all the same as far as response time, and the Koni tech could not give you a straight answer why would you go through trouble of changing the coilovers, adjusting ride height, and alignment? After your last experience with the Koni's, I would either wait for a "matched set", or switch to another brand.

FWIW, 150+/- has been great with the bilstein/eibach setup for a couple of years now (short bursts, not 50-100 miles). And when I had a noisy shock (rear) on my install, DR just shipped me a new one and dealt with the warranty issues himself (or Jeannie dealt with it). How helpfull has your original vendor been with resolving this?

Anyway, I would not bother with the install if they don't perform to your satisfaction on the bench. See if Koni will get you another set of rears, maybe get your original vendor involved in this. It will take the better part of a day to get it done (at least on your back in the driveway) and adjust the ride height, and if it is not right you get to do it over again. With the open road racing you do, I would want it perfect, not "close enough". They should all rebound/extend equally at the same settings, not 2:1. But I am not an expert on this, so YMMV.

Jim

Garth S

I rather suspect that the compression effect of a new teflon seal against the piston rod of an 'out-of-the box' shock is bound to influence the free extension time.
Even with no miles, when installed, the ~850 lbs/corner static weight being held up by a ~250 lbs.in spring under significant compression would tend to nullify that 'newness' effect and allow the shock to respond to compression/rebound as designed.
While none of this may be relevant, I would at least take some comfort if the product rep had at least the huevos to murmur this techno babble in my ear.

heinrich

BILL

That dyno is not necessary. You have already prefromed those tests manually. All the dyno will tell you (ha! dyno, my ***) is that same data. In other words you have manually dynoed the shocks. If they are SO FAR OFF that you can detect the performance difference visually, then a dyno will tell you nothing interesting. Again, my best advice is to instal them and drive for a hundred miles. THEN test again.

Bill Ball

I found a Koni tech who seemed pretty knowledgeable hanging out on a ricer hop-up message board. I sent him a note yesterday asking for advice. No response yet. Problem is, I am running out of time. I suppose I should just order an alternative, like the Bilsteins, and then punt these Konis onto eBay after they are sorted out, but I'm trying not to be stupid with money. I've tried contacting the original vendor recently but have not heard back.

pmotts

Bill,
I wouldn't want to install shocks that were suspect but then I don't have a lot of spare time on my hands. Have you asked Koni to send you another set? I am not very smart about suspension but is there a shop somewhere close to you that has a way to further check your shocks?

Bill Ball

I've tried searching for local suspension shops. Nothing convenient yet. I'll give the other Koni rep till mid-day to respond then I'll call their tech line again and see what they will do. I do have a weight bench that I never use for its intended purpose, so maybe I will put it to use with the shocks.

heinrich

Wow Bill -- seems like a LOT more effort than one should have to deal with.

Bill Ball

Maybe I make things harder than they should be. I could slap them on and drive it. I would have felt better if the Koni rep had said something like, "Oh, yeah, that happens all the time and means nothing. The shocks are good." But that's not what I heard.