Back to the beginning. GC Konis or Bilstein re-valves, same price range.

 

Well the koni has a better adjuster... if you get a good revalve the koni's are great... but I have no experience with Bilstien... in hind sight Id get my valving with more bump and less rebound... I run mine near full soft (single adjustable) Im going to have them rebuilt at some point to be double adjustable and ask for more compression and less rebound

 

The difference is an aggressive revalving, 571lb springs, Al pillowball tophats. The CS can handle spring rates up to about 750lbs with no issues. It basically addresses the only weaknesses of the KW V3 (little soft, OEM tophats).


If you track or autoX on the east coast (crappy, bumpy tracks and lots) then the CS is great.

 

Call KW, same valving.

 

Well than apparently the V3 and the CS can handle up to ~750lbs.

 

There is a significant difference between twin tube (Koni, KW) and mono tube shocks (Moton, Penske, Bilstien, AST, Koni, etc). This is most noticeable with high rate springs when driving on a rough road and driving a car at the limit during autocross. I would rather revalve a set of non adjustable mono tube shocks (i.e. Bilstien) multiple times until correct than have a set of double adjustable twin tube shocks.

I did the research for one year or so, bought used Penske 8100s for $1900, rebuilt them, revalved them four or so times and ended up very happy with the result. Total cost including a home made shock dyno, nitrogen tank, filler tool, and parts was about $2600. I can now rebuild and revalve them when ever I want to, but once the valving is in the ball park you are set and can fine tune with adjusters.

Shocks have oil inside and it needs to be changed periodically to maintain performance an minimize wear. The Motons must likely use synthetic oil to enable longer use. Amsoil synthetic is what I put in my Penskes. If you don't have synthetic in them then the oil will break down faster and require rebuilding more often. Just like I change my engine oil religiously I plan to rebuild the Penskes every 20k miles or so (annually for me). This is what Penske recommends for their racing shocks with non-synthetic oil.

Some Photos

 

True. I have SRC's and love them. They will handle spring rates all the way from 678lbs - 1000lbs... like champs. VERY daily driveable. In fact, feels better than stock at full soft compression and 8 clicks up rebound. IMHO the valving is near perfect from the factory for STR. Tein support is great. I have tried a ton of different spring rate combos so far. Shocks are FAR more adjustable than Motons... (Height wise...yes, only 16 clicks of adjustability.... )of course everyone is going to disagree with me.. but think about it... these have fully adjustable bottom mounts, threaded bodies, and come with the pillow ball mounts. For that kind of money... you can't beat them.

What I'm trying to say is... you can adjust ride height on the SRC's by just raising the shock body and not raising the spring perch collar... no preloading of springs (I guess wouldn't happen anyway because of the helpers...) but, you could run just springs and eliminate the helpers on the SRC's if you wanted to.

BTW, SRC's CAN run the same height / diameter springs front to rear... VERY VERY nice...

So, basically, for the money.. you can't do better than the SRC's... in my opinion.

 

LOL, I see you have the same love of McMaster-Carr that I do, including the awesome yellow compartment things.

This idea does appeal to me a lot. How did you learn how to do all of this? By this, I mean both the practical knowledge of how to rebuild a shock as well as the theory behind what characteristics you wanted. Is it in Penske's documentation?

I am a mechanical engineer, but I don't do vibrations in my work. I did well in vibrations in school, but that's just undergraduate level basics. So basically I should be able to learn this stuff pretty quickly if I knew where to learn it, but I don't know it right now. And especially when it comes to the actual process of rebuilding a shock, I know pretty much nothing beyond a basic idea of what parts would go into a shock.

It looks like you're using an air cylinder for the shock dyno - can you consistently get the right variation in speeds with that?

 

Mike - thanks for the input on the SRCs. I'm assuming you don't get a dyno chart with those or anything like that? I'm a bit worried based on what I've read that the Teins are not consistent in their damping, and/or have very odd curves.

 

Mike, people are are also insanely fast on stock shocks.
I don't think SRC's would work with 678 lb springs without a revalve. They simply have way too much rebound even for the 900 lb springs.
I don't doubt that people can drive fast on them but they are by no means the best thing out there even when considering the price point.