anorexicpoodle

First Ill preface this post with my own hair-brained theory about suspension tuning: Suspension modifications should make the car easier to drive, thus encouraging the driver to try going faster and allow the driver to devote brainpower to other things than keeping the car on the track. This unequivocally results in faster more consistent times. My goal in this post is to simply chronicle my experience with these and hopefully inform others future purchase decisions since there seems to be a pretty big vacuum of hard data on these shocks.

The Tein SRC seems to be the favorite shock of the S2K challenge which hosts some of the fastest S2K drivers in California. As I stepped up from Stock to street class I installed some Evasive spec SRC's in the hopes that they would provide the promised improved grip and confidence on the bumpy and often unforgiving socal track surfaces and provide me a platform I could grow with as I continued to tune the car.

Unfortunately this proved not to be the case and finally at my wits end and infuriated by having spent over 5 months and a half dozen track days tinkering to still have a car that drove like a meth addicted axe murderer I went in search of an explanation. I wanted to understand if I was missing the boat on tuning something or if I was trying to swim uphill against a shock that wouldn't do what I wanted. I enlisted the help of suspension guru Guy Ankeney to help explain why the car behaved as it did and find a resolution.

Guy instructed me to deliver just the shocks, no springs, and to not tell me how the car behaved. He didn't want his analysis tainted by my opinions. He called me shortly after and said "let me tell you how I think this car would handle..." and proceeded to absolutely nail every problem I had been fighting. He recommended that the only way he was able to get these even close to a range that would result in a car that handled well would be to run the fronts at full soft compression and full stiff rebound, and the rears at full soft compression and rebound but it would still be sub-optimal. The best course of action is to re-valve.

Now I was curious. Evasive had supposedly tuned these shocks to handle bumpy tracks in the same vein that Counterspace garage had tuned the CSG spec SRC's. So the question is are the CSG actually different? These were both options I considered. Would it be worth re-valving to the CSG spec? Mike was kind enough to set me up with rhouck who was very fast driver on CSG spec SRC's whose car was mothballed temporarily. He loaned me a pair of the CSG valved variant to measure and see how different they were. Again back to the dyno, where Guy informed me that while the CSG valving was definitely going in the right direction, it wasnt quite enough to make the costs to revalve to that spec worth the expense. Instead he jotted down some numbers that I relayed to tein for the re-valve. The 3 dyno plots below are as follows:

The evasive curves are the best that they could be, i.e. at the full soft comp front/ full stiff rebound front and full soft rear all around.

The CSG curves shown are as they came off rhoucks car set to "fast" (1:59 at Buttonwillow with OEM aero and eventually much faster with aero and forced induction) which is nearer the middle of the adjustment range front and rear.

The 3rd set of dynos is off the Tein re-valved shocks after consulting with Guy.






Initial impressions of the new valving setup are extremely good. The car is absolutely unflappable. It never feels out of sort and is just easy to drive. Additionally the car is extraordinarily comfortable now on the street. It absorbs the road so well even on 900lb front springs/780lb rear springs that you dont realize how fast you are going, whereas previously going even the speed limit on surface streets had you crashing over every bump and pothole. In my first test at AutoX I found myself inadvertently running out of gear because I could get on the throttle that early due to the extreme stability and confidence the car gave me.

Its worth noting that doing back to back rides in my car and Guys car on his tuned Penskes, the elements of the ride quality are the same, but Guys car on Penskes is like watching a movie in HD vs my car on the Teins is closer to watching a VHS tape of the same. They both seem to get you in the same direction but the Penskes do it with much finer control and a tangible ride quality missing in the Tein shock.

Here is what I have learned:

• On full soft compression the evasive are very close to the CSG set in mid-range but the Evasive are ultimately still significantly stiffer which isn't necessarily a good thing.
• The rebound curves of the Evasive and CSG are again very close in the front, but in the rear things diverge. One of the interesting notes was after delivering the CSG shocks Guy noted "theres a lot of bumpstop wear on the rears" which would seem to be supported by the huge amount of rebound the rears seem to have.
• The SRC only has about 50-70lbs of swing in compression adjustment, regardless of the valve (evasive and CSG use different base valves) so if you aren't in the ballpark, you aren't getting there.
• The nose point on the evasives at anything BUT full soft was over 25lbs. This nose point (the transition from compression to rebound) is what affects how the shock deals with small imperfections. This high nose point is what caused the skittishness. The high rear nose point on the Evasive is likely what caused the twitchiness at Autoclub on the banking when crossing the pavement joints.
• Whats interesting to note is the CSG valving was developed using only driver feedback and in many ways was going in the same direction as what Guy proposed but just wasn't nearly as aggressive. The proposed valving took the direction the CSG's went in and turned the volume to 11.
• The dyno curves of the re-valved Teins are not on even adjustments. Every corner is at subtly different settings to yield even dyno curves. I found this very curious.
• Building custom SRC's costs MORE than just buying Penskes out of the gate and Teins re-valving costs are easily double what most other shock builders charge per corner. It would certainly be more palatable if Tein would allow 3rd parties to rebuild their shocks.
• Finally and most importantly, Guy, in an afternoon with my shocks on a dyno was able to accomplish more than I had in months of testing at the track even with multiple drivers in the car etc and it was done with less effort and frustration and most importantly cost. I would say that from now on the shock dyno is one of my first stops when setting up new suspension, and those of you out there that have dialed it in by feel, might still have an amazing revelation if you had an experienced shock tuner take a swing at it.
  

All this results in a shock setup that interprets the road without upsetting the chassis or shocking the tire which in the end provides more ultimate grip.

Huge thanks to Guy Ankeney at Ankeney Racing http://ankenyracingenterprises.com/ And Mike (Psycoazn) at Counterspace garage http://counterspacegarage.com/ for working with me on this endeavour and to rhouck for letting me take his car apart in the interest of science.

While I wont be at the track in the S2000 again until June due to my Lemons schedule (wish us luck in Utah), stay tuned for updates and some guest driver feedback on the car as well since there are much faster drivers than me out there with an interest in trying the results of this work.

andrewhake

EXCELLENT info! Thanks for sharing!

sillyboybmxer

Great write up.
Hope this helps a lot of people

Bullwings

Good stuff!

I've always been some what hesitant to try out the Teins.

That said, I think i'm gonna be chilling in Street class for a while. I'm gonna keep it simple, keep the modding down, and just focus on the driving. I have another OEM setup with 50K miles on it ready to swap in since my current setup has 86K on it.

The current rules setup allows my car to be competitive as is in Street - now it's all on the driver.

anorexicpoodle

Honestly if I had known then what I know now I would have just started with Penske and enlisted a shock expert like Guy from the beginning. I would have easily been ahead by over a grand if I had gone that route versus the months of frustrating testing and tuning followed by the inevitable and expensive re-valving.

I would be less hesitant about the state of these shocks if Tein allowed 3rd parties to purchase parts for re-valving. Honestly from a component perspective they are nice shocks. Externally they check all the boxes, but the state of manufacturer support makes them a difficult sell as a long term platform.

Sebring AP1

Thanks for confirming the majority of my speculation. Really awesome that you did this, now hopefully you don't kick my ass left and right in street class (Although my car may be sold in July)

sillyboybmxer

Ameer!!!!
Did you find a gt3rs????? dont tell me you are gonna hit the track in the ST instead

Sebring AP1

LMFAO hey screw you guys the ST is cool.

No gt3rs haha. But if I do pick up another weekend car yes it will be RWD. The cars not sold yet I just have a very interested friend. Who is probably reading this. Maybe he will back out maybe he won't. Either way works for me lol

sillyboybmxer

Well, .....not to derail this thread, but Holla at a brotha if those jrz or volks need to leave.

Back on topic, I never understood why the SRC is THE choice. Seems like they were overpriced IMO. ....or maybe I just have a hard time taking Tein seriously/or that they build a high end shock with all the low end stuff they also produce. Maybe the hype will die after this thread

Sebring AP1

The hype should have never existed IMO. I never considered them "THE" shock to use. Maybe if you're a ricer. And use ricer math and logic to calculate laptimes

Edit: I am going to preface this by saying yes I am a hater and none of this opinion is grounded in fact. So please don't try and have an argument with me and go into detail