It's been stated that high end $$$ custom valved s2000 shocks for autocross tend to be significantly stiffer than either stock or the koni yellows. Has anyone had the koni yellows revalved with any success?

 

I don't know if anyone's put revalved Konis on an S2000, but it's fairly common practice for other cars. The two names I usually hear associated with Koni revalving are Pro Parts USA (West Coast) and Truechoice (East Coast).

The problem with revalving Konis is that, once you're done, your shocks cost nearly as much as the entry level shocks offered by Moton, JRZ, etc., but they still don't have the features and quality of construction of the higher end stuff. If you've already got a set of Konis lying around, though, it might make sense to do.

As an aside, having now spent extensive time driving both a car with JRZs and more road course-type valving (i.e. soft by autocross standards) and the ex-McKee car with Penskes and "stiff as piss" autocross valving, I'm not convinced the latter is any quicker than the former. I suspect my JRZs are still stiffer than off-the-shelf Konis, though.

Steve

 

Steve:

Interesting, I find my JRZ (3ways) like to be set softer than I usually run on the race track.

OT I know.

 

I'm convinced that the "stiff as piss" Penskes are faster if you've got the talent of someone like Andy McKee. For us mere mortals, I think its a wash. Steve's car with JRZ's is much easier to drive than my car with the Penskes. But, it washes out about even as far as times.

Also, for what its worth... Stiff as piss rebound valving and a more moderate compression valving seemed to be a bad idea. At least Steve and I both found the car to be... bitey. Yeah... that's the word, bitey.

Andy H.

 

I was thinking stiffer compression on the front than the rear. Typical adjustmnet with koni yellows is full stiff rebound on front, softer rear. Those I've seen with DAs (not many in my case) increase (stiffen) the compression in front as compared to the rear. Discussions about spring rates, noteably a move by Honda toward more balance between front and rear in later models, rather than 218 front and 291 rear ('00), seems to support this.

I'm not thinking "stiff as piss" but maybe the koni yellows would beneift from some different (stiffer) compression for auto-X. I'm just trying to get away with an improvement and not spend too much money. A set of revalved konis seems from the quotes I've gotten about half the entry level price of Penske, JRZ, etc. Perhaps I'm confused by the numbers $$$. If the $$ are about equal then that is a different story.

I've also have been unable to get any real numbers as to valving. Andy's (i believe) write up on the 2002 road to the nationals points out what adjustment he made to the Penske's (half turn from full stiff, etc.) but as he also points out this is pretty useless unless you know the valving.

I've read about others in different cars (bmws here) having revalved bilsteins, etc with some success.
But they had some guidelines.

I believe entry level (SA) penske, for instance, is $550 a corner. A revalved koni, $250 a corner.

 

A bunch of data points:

• Mitch Fagundes has revalved non-adjustable Bilsteins on his car. They evidently work for him, as he's won both West Coast Tours so far this year.
  
  
• More on the stiff-as-piss front: Anna Goeke mentioned at the Arizona Tour that she actually preferred driving payneinthe's stock-shocked car over Joe's ultra-stiff one.
  
  
• Highly-unscientific test: if you pop the trunk on Joe's Koni-equipped (their high-end shocks, not Koni Sports), Gary Thomason / Pro Parts (?) -valved car and try to bounce the back end, it's difficult to get it to move appreciably -- you get the feeling that it's budging an eighth of an inch or two, but there's no feeling of suspension compliance in the conventional sense. The same is true on Andy Howe's Penske-equipped, Andy McKee / Guy Ankeny-valved car. On my JRZ-equipped, Greg Fordahl / Fordahl Motorsports-valved car, it gives about an inch, but does not bounce.
  
  Has anyone tried a similar test on a Koni or stock-shocked car?
  
  
• About pricing -- Tire Rack lists Koni Yellows as $157 a pop, and Pro Parts will rebuild Yellows for $135 per shock, for a total of $292 per corner before shipping, dismounting / remounting, etc. The cost of converting Koni Yellows to double-adjustable will make your nose bleed. I haven't shopped for JRZs or Motons recently, but I was under the impression that if you asked the right people nicely, their entry-level stuff was available for around $500-$600 per corner; that's still a pretty significant price difference. You can get Advance Design shocks for $400 a corner, and I think you can get Koni 82 series shocks for around the same amount.

Is it worth it? Dunno. I'd definitely spend money on a big bar and fresh Hoosiers for every event before going for high-end shocks.

Steve

 

I went to the garage, popped open the trunk and gave the push test. Stock shocks moved about an inch, and didn't bounce.

Have a saner bar set on full stiff and it stays there, even on bad aslphalt. Fresh tires (hoosier when appropriate, Khumo for entertainment and bad surfaces) are in the budget and in the garage.

Ian (MrSideways) drove my car once with saner bar, an alighment I like -- 1.75 chamber f; -2.25R; o toe front; 1/4 toe in R -- on fresh Khumos, terrible surface. He thought he could drive his car flat out through the slalom, with my car he could not, which he attributed to shocks. Got me thinking.

I've read little about Advance Design. They look good on paper. But what I have read indicates that they will need to be rebuilt after 8,000 miles. They simply don't hold up. I have no idea if the information is crediable (I read it on the Web!).

Koni says, through them, DAs are $550 a corner.

I'll put a lot of runs on the car tomorrow and see if I can clearly define what I want the shocks to accomplish. Right now during the turn in phase on a tight corner the inside rear feels like its way up in the rear. I thought that stiffer compression in the front would help keep the back inside wheel planted.

Tom

 

I have a set of DA revalved Koni yellows that I bought through G.H. Sharp last summer. Unfortunately, I was unable to run them at the Nationals due to a work conflict, and I've only run them about 4 or 5 times since I installed them.

I don't know the details of their specs, but I'm sure Koni still has the data. I suppose it is too early to know whether they're good or not. I believe they increased the compression, front and rear, more on the fronts. I've been running them with a solid 1.25 inch bar that I had custom built before anything else was available, back in 2000. I'm planning on installing a Gendron solid bar pretty soon, and then I'll see how the car feels. The best feedback on the car would be if I can get a top S2000 driver to see what he or she thinks.

Steve