DB2-R81

Is anyone willing to reveal a bit of info on rebuilding, revalving, double adjustable conversion, shortening Koni Sport dampers?

How did you present your needs? Just your spring rates, application and they gave you a graph and your dampers back? Or did you provide spring rates wheel rates, motion ratio, corner weights, un-sprung weight, shaft speeds in ips, hand drawn graphs, digressive valving, progressive valving, application and running surface? Were they able to meet your requirements, provide compression high, low speed and rebound high speed low speed valving?

These seem to be the major service shops to do the job any recommendations of who to send them to? Was there turnaround time reasonable? Have I missed any shops? Names of people to discus my requirements with?

ProPartsUSA
Canoga Park, CA

TrueChoice Motorsports
Hilliard, Ohio

Koni North America
Hebron, KY

Or should I be looking at Penske, Ohlins and another few decimal points in the cost?

SPiFF

If you are just going to take yellows and pay out the **** to shorten, re-valve, and make them double adjustable, I would just buy Advance Design stuff instead. You will probably pay the same, or maybe even a little less, and end up with a better shock.

Just my 2 Yen. At least that is what I would do if I had $399*4 to spend for shocks. Sadly I don't. So it is off the shelf yellows and <600# spring rates for me.


[Modified by SPiFF, 10:24 PM 2/9/2002]

Catch 22

My yellows were shortened and revalved by Koni (through OPM Motorsports).
I honestly didn't have much to do with it since Tom at OPM handled the set-up with Koni. Nevertheless I'm pretty sure all the info they needed was the vehicle, the gross weight with driver, and the spring rates.

I will drive on this set-up for the first time next weekend, so I don't have any practical feedback yet. I will say that the revalved Koni yellows are extremely popular with club racers and are quite certainly the most bang for the buck. I know the top 3 ITA cars at this year's ARRC (CRX, CRX, Integra. All OPM Cars) were all wearing Konis.

DB2-R81

Hey SPiFF,

Thanks for the reply, looking at catalogs the cost to rebuild my extra set of Koni's should be in the neighbourhood of $1500.00. Maybe I have too much of a sentimental attachment to them, their performance and reliability has been above average in the past. It seems like such a waste of tuning knowledge and materials to pitch them a start with completely new set of dampers but maybe it's time to move on. Some of my hesitation stems from no local knowledge or applications of the Advanced Design Dampers. There does not seem to be much correspondence here or anywhere on the Internet in regards to their use I have found. Do you know anyone who is presently using them that might be willing to talk to me about them?

DB2-R81

Hey RoadRacer,

So Tom sent them to Koni North America. Did they provide you with force, velocity dyno graph? Do you happen to know if they were valved to be progressive in bump, digressive in bump, progressive in rebound, digressive in rebound? Thanks.


[Modified by DB1-R81, 8:01 PM 2/9/2002]

SPiFF

I am a little left of center on this .. because like RoadRacer sais, the revalved Koni is a popular choice with racers. Probably because you can pay as you go. Shocks this year, re-valve next year, etc.

I have only seen one set of AD shocks and the car they are on is not finished. So I have not seen it run. But they get high marks from me for design and build quality. They are super light, well built, and nice and short out of the box. I think AD is a spin off of Ground Control, so they use the same type of material as the GC coil over parts. Another nice thing is they will thread the body so the GC perch will go right on the shock.

Catch 22

OPM sends them off to Koni. I'm not sure if Koni accepts jobs from individuals, I think they just take jobbers from shops. Koni and OPM have worked together for years and my shocks were returned within 3 weeks.

The shocks were dyno'd after the rebuild, but I don't have the graphs. Don't want 'em, didn't ask for them. I'm a "feel" driver who wouldn't understand or care about a shock dyno graph anyway. I either like the way the car handles or I don't, period.
I'm sure you could get the dyno info if you wanted it.

sjasmund

Lee Grimes works for Koni and drives IT and Prod Honda's. He's an excellent source of information for and can put you on the right path with the Koni's. His work # is: (800) 922-2616 x16

I have Penske's on my CRX and the prices were competitive with the Koni's. FWIW, the guys at Penske were great to work with. I would have thought that a company supplying CART, F1, etc. would care less about an IT team. We sat with them when they dyno'ed the shocks. We took other shocks (Koni, Tokico) to compare against and worked with them to determine how we wanted them valved. After our tests, they called US to find out if everything went okay.

DB2-R81

Hey Roadracer,

Thanks, Koni NA will provide service for individuals. And thanks for the offer on the graphs. I think I know what I need for my car based on suspension specifications, I was just curious to find out if people are trying valving outside the norm and having success.

I am willing to bet you use an air pressure gauge, feel only goes as for as what you can communicate to your engineers, not that I could afford one anyway.

Hracer

As Scott G. said, we have the Koni shortened revalved, double adjustables (just about everything you can do to a Koni) and are mounted inverted. This is on the car that finished 2nd at the ARRC. The shocks are from OPM and been done to Tom's specs for a CRX with our spring rates (500f 700r). (We actually got these shocks from another CRX, so we're not the original buyers.) OPM also sells the single adj. Koni revalved shocks that are mounted normally. We have those on our other CRX. Those are cheaper and are really good. I can feel a difference between those and the better double adj. shocks on the track. Simply put, the car has a stiffer ride (even though both CRXs run the same spring rates) and it handles rough tracks and bumps noticeably better. The car basically is a little more stable going though bumps and curbs. These differences can be felt from the driver's seat and I didn't really need to see spec sheets to see the differnece. We've sent the double adj. over to Koni to get them rebuilt because we got the ARRC contingency, so we should get them back with a graph from Koni NA.

civicrr

Here is the link. http://www.advance-design.com/

DB2-R81

Thanks for the tips guys, Sjasmund I will give Lee a call.

grippgoat

It's important to note the difference between custom-valving and double-adjustable conversion. I talked to someone, I think it was pro parts, through email asking about it. Custom-valving is about $100/shock. Conversion to double adjustable is about $400/shock. Also, in the case of the NSX, it was going to be more expensive for the double-adjustable conversion because the NSX has an eyelet on the bottom of the shock where it attaches to the suspension (much like a G3 non-type-r / civic rear), so they would have to put the compression adjustment on the side of the shock.

Anyway.... My feelings are custom valving is probably the best bang for the buck if you can get adequate performance (which is easier if you have only a race car). However, if you really want double-adjustable, you're probably better of with Advance Designs at the $400 per shock price point because:

1) you can sell your Konis and coil-over adapter sleeves to someone else if they're not dead, or keep them as backup shocks in case you need to service or re-valve another shock.

2) you don't have to leave the car on jack-stands (if your Konis are your only shocks) and you can keep doing events while you wait for the new shocks (and it'll take at least a month from everyone I've talked to)
3) you get a real threaded body
4) the advance designs are WAAAAAAAAAAAAAAAAAAAAAAY lighter than the steel-bodied Konis giving you a big unsprung weight advantage
5) both adjustments are easily accessible at the top of the shock, whereas I think converted Koni sports are a pain to adjust the compression on (gotta at least get under the car if not remove the shock completely).

Disclaimer: I haven't used advanced design shocks, double-adjustable-converted Koni Sports, or custom valved Koni sports. I have, however, picked up a full spring/strut assembly for my NSX with both a Koni sport (with GC sleeves and upper mounts), an Advance design (with the same upper mount), and a Tein RA, and the GC Advance Design by far was the lightest. Guessing, I'd say 20-30 pounds for the Koni sport, ~15 pounds for the Tein (I could look it up but I'm lazy), and probably 10 for the GC AD.

My biggest concern with getting custom-valved shocks, at least on a car that wouldn't have a lot of feedback data like the NSX, is that I'd sped $100/shock, get 'em back, and still wouldn't like 'em, then have to give feedback and do it again, and wait for turn-around again, etc, by which point I've wasted a LOT of time (rather intangible to put a price on), and I've spent half the money I could have spent on a double-adjustible conversion or some Advance Design shocks.

Other factors to keep in mind are things like a nitrogen pressurized option, where you can adjust the amount of pressure in the shock, which has an effect similar to adjusting your spring rates. I know you can get that on $1000+/shock JRZs and you can get it on $700/shock Penskes. I'm not sure what's available in that respect at lower price points. I also don't know if the Ground Control Advance Designs have that option.

And to look at it at a bit of a different angle, if I were going to spend more than just the $100/shock for a re-valve, I certainly wouldn't be doing my homework on an internet message board. I'd be reading up on shock technology and talking on the phone with people who do shocks for a living. I also know that in our region, most of the people who autocross and are really fast dropped the money for JRZs from Fordahl Motorsports, and haven't looked back. I even know one guy who spent $5000 for JRZs for his Neon (yes, the shocks are worth almost as much as the rest of the car) and swears they are worth every penny. However, on the S4 he'll be co-driving this year, they are going with some Double-Adjustable inverted-mounted Penskes from some place down in California at I think the $700/shock (not including fabrication and mounting) price point.

You might even want to look around and see if you can find some used fancy shocks. I seem to remember recently seeing a set of almost brand-new advance designs for sale. I can't remember where I saw that, though.

-Mike

JeffS

I just bought a second-hand set of A-D shocks and I can testify to how light they are. I was shocked when I picked them up. I'd say all four dampers combined weigh what one of my last aftermarket shocks did (Tein HA's). I haven't installed, or run them though... the car won't be ready for probably 2 more months.