DB944T

I just adjusted the rear Konis that I put on the car about 500 miles ago.(Yellows all around, from paragon) I did it with them in the car, just removed the bottom bolt and the bump stop.

the question is, I found that the force to compress them was radically different on each side. One I could compress with one hand (slowly, with a solid push). the other was much harder, it took both hands and all my strength to compress it.the rebound seemed slower too. They were both full-soft when I did this - which shouldn't matter since I was compressing them.

Should I worry? Do I have a bad shock? Is this normal?

Also - I firmed the rears one turn, and the fronts 1 1/4 turn. the car went from fairly neutral to noticeable throttle-on oversteer. Springs are stock.I expected it to stay neutral or add understeer by dialing the fronts a touch stiffer. Am I missing something?

help appreciated
Dave

ribs

I thought I had 2 defective konis when I was getting ready to install my rears. I would put them both on full soft, both on full hard, and do several rounds of comparitive timing for rebound after compressing them both fully. I was shocked that one was faster rebounding on full hard than the other shock was at full soft. I was getting really angry and about to call up skip and scream and curse (just kidding), but then I thought about it for a second, and I was playing with one shock a lot more, twisting it and compressing it to find a setting that looked right (I have no idea what really looks right, but anyways)...then it dawned on me...I had "warmed up" this shock more than the other.

The simple way to fix this is to compress and rebound both shocks about 10 or 20 times (thats about how many I did) to get the juices inside of them flowing, then do your tests. I was amazed at how syncronously they rebounded after being warmed up in any setting firm or soft...after they were warmed up it was easy twisting them both about 1/2 way between firm and soft then measuring accurately how close I got them to each other.

Your shocks are fine...just warm them up first. Good luck.

ribs

I didn't read the bottom of your post...I believe the front koni inserts (thats what you have, right? The ones where you had to hack apart your stock struts and re-use the housing) have more rotations of adjustability than the rears. They may have a more linear adjustibility from the screw on top and the rears may have more of an exponential adjustibility. I would leave the rears alone and futz with the fronts, making them fractionally stiffer, going and doing some donuts in a parking lot, hop out, and adjust them according to how you felt they should be adjusted. My car is set up for massive (i.e. toyota camry style) understeer right now as I have 400# front springs and stock t-bars installed right now. I have the fronts on full soft and the rears on about 1/2 stiff, and the car still skids like a front driver. I have the 30mm torsion bars sitting in my rear seat...I just have to get the ***** and energy up to put them in. After that, I'll be messing with shock/strut settings. Hope this helps a bit, too.

ribs

Don't you like initial D? You should keep your car set up as a driftmobile! I'm getting an '86 corolla as my next beater so I can drive sideways everywhere!

Here are a couple drift videos for ya...:
<a href="http://ribs.americainteractive.com/videos/carvideos/AE86vsAltezzaB.mpeg" target="_blank">'86 corolla vs. altezza drifting</a>
<a href="http://ribs.americainteractive.com/videos/carvideos/junsupra_short.mpeg" target="_blank">Insane supra drifing around the track</a>
<a href="http://ribs.americainteractive.com/videos/carvideos/944_commercial.mpeg" target="_blank">951S drifting in slow motion with tons of smoke pouring out of the rear commercial</a>

Keep it driftin'!

Dave E

One word..... BILSTEIN

luckett

That's a helpful comment...Might as well have just said "YO!!!"

Bilteins are no better or worse than Konis. They both make great products and the purchase decision is usually based personal preference.

Sounds like you did not have the rears both at full soft like you thought. Try to put them both at full hard and test, then full soft and test again to be sure the rates are changing like they should. If not, either your not adjusting them properly, or they are defective. If you think they are defective, contact paragon/koni and they will be able to test them on a shock dyno.

When you make adjustments, it's better to make the change to one side at a time and test the change so you have a better point of reference for what the change is doing. Since the fronts are easily adjustable, play with them first and if you can't get the balance you want from the fronts, then chnage the rears.

Dave E

chris, all obnoxious comments aside.. I also have koni's and it sounds more like you have a bad shock. mine were both the same resistance when I adjusted them and I would think I I'd replace the unusual untin if it were on my car. I generally think Bilstein makes a more appropriate shock for track use. I understand they are more durable as well as having a regressive valving. When I come up with the funds needed to replace my shocks/struts I will definitely be using custom valved bilstein's. I currently have the 89' turbo setup, but it is woefully inadequate for track use. <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

Larry Parker

we do alot of shock dynoing and we have found that most mass produced shock have a
very large part to part variation between them
both in gas force, compression and rebound forces.......

Also we find many shocks adjusters do not work in a linear fashion, just ramping up forces at the very end.......

We found some brands adjusters do nothing at all.....

DB944T

Thanks for the comments.

Ribs - yeah the oversteer is fun, but not what I want for the street. I have reverted to driving like a teenager who watches too much "Starsky and Hutch" lately (and you can date me by that), but that's not really a good thing.

My goal is a relatively neutral set-up, then play with the tire pressures to get the car to rotate for AutoX. I'm just getting started with running cones, and that's what caused me to start playing in the first place.

Sounds like the next step is to pull them off completely and get a better check to see if they are defective. good points about the variation/non-linearity in adjustability. I'll take that into account. but the difference was in compression which isn't adjustable on these Koni yellow sports.

And yes, I understand the quality/cost tradeoffs, but the budget is constrained by external forces (read wife).

Dave

Skip

Shock testing by hand is futile - unless the shock or strut is completely failed, there's really no way to test the compression or rebound forces of a Koni Sport by hand. While it is true that the compression and rebound forces do change with heat - the real effect you may be feeling is fluid displacement, pressure buildup, and lubrication changes as the friction surfaces are "made ready". A shock dyno is the only way to determine what variances or slight failures may exist. Every Koni damper is electronically tested - the rate of change for adjustment, while not completely linear, is precise by relative measure.

If by visual inspection, or by gross driving perception, you feel that a Koni is defective - they should be sent to Koni-NA in Hebron, KY for inspection and replacement. <a href="http://www.koni-na.com" target="_blank">www.koni-na.com</a>

For your throttle-on oversteer - it could be that your perception of the oversteer has been moved to a new (higher) level with increased cornering speeds. Not sure if you were track testing, as it's hard to find open spaces to effectively test such things on the street, but if your entry/exit speeds are increasing due to added cornering performance brought on by the upgrade or adjustment to the shocks then it's possible you are experiencing a loss of adhesion at a greater angle or different weight distribution. Some handling characteristics can be masked by others - road temperature - type - angle, tire pressure, line-in/out, etc can cause wildly varying results. In general, oversteer means the rear is too tight - loosen to taste, or stiffen the front. Throttle-on oversteer can mean many things - especially on a Turbo if in the boost - if not equipped with an LSD it can simply be a change in driving style is needed (late brake, etc).

I'd be very interested in seeing any empirical data from dyno testing of mass produced shocks, or otherwise (not sure of the criteria).

Good Luck!

SGOGT4

Hoe easy or hard is it to adjust the rear Koni yellows once they are installed on the car? I was just thinking about softening them up a bit for Chicago street driving this morning. I know the fronts are real easy, but the rears I am in the dark on.

Thanks

Skip

The easiest way is to remove them from the car completely, but some choose to do it with just the bottom disconnected, You have to remove the bump rubber from the casing, then carefully compress the shock until the tabs engage (by feel), then twist. For more info, see the Koni adjustment procedures:

<a href="http://www.tech-session.com/Paragon/Info/koni_adjustment_procedures.htm" target="_blank">Koni Adjustment</a>

SGOGT4

thanks as always

DB944T

Good info skip - I wondered if heat from the exhaust would have an effect on that side. something like the shock oil flowed downward easier while it was sitting. In driving, there doesn't seem to be any major difference L-R. I think I'll live with it a while and see how it goes.

And you could be right about the increased speeds. I went from dead shocks, to new shocks, to stiff set shocks.

The testing was unscientific on exit ramps and other turns I take regularly. I used to feel the nose lift and go wide with throttle, now it stays locked in and its pretty easy to get the rear out. I'll have it out AutoXing next week, so we will see what happens there.

Mark Parker

And while the subject of oversteer/stiff/loose is open. allow me to poll ya'll on the subject of tire pressure. I too am new to the autox game, having just run in my second last Sunday. I started off by following the recommendations on the SCCA site about running tire pressures of 40-43 psi, and equal at all four corners for my rwd car. I've settled at 40 psi front (85.5 na with 215/60 15 all around) and the front wheels are very well behaved. But my last run was at 39 psi rear, and it's amazing how quickly I can break the rear tires with any kind of throttle. It's hard to come out of a turn because I can't seem to hook up with the rears. I've been advised to try a 4-5 psi differential between frt/rear. Any thoughts from this group would be greatly appreciated.