coilover options

[RecceDG]

First, his claim that all Japanese coilovers are crap is ridiculous.

Read the article more closely - I didn't claim that all Japanese shocks were crap; rather, I state that all the Japanese shocks I tested (and I tested a lot of them) were crap, and so there was a very good chance that a Japanese shock bought untested would be crap.

And hell yeah, the ones I tested were horrible.

A) who takes their brand new $2500 coilover set to him for revalving and/or shock dynoing?

Actually, quite a few serious racers. I was one of the first people to start publishing dyno results and I had more than a few customers ship shocks directly from the manufacturer to my shop for dynoing.

And shocks don't really deteriorate gradually. There's a slight change in performance over time as seals wear, oil gets dirty... but that change is small. It's when something lets loose ("blow") that you get a drastic change. So except in the case of a blown shock, age really doesn't play a part.

B) Most of the <$2000 japanese coilovers aren't made in Japan anymore. They're made in China and Taiwan, where (on the whole) quality control is not what it is in Japan.

That really doesn't make much difference. Off-brand is off-brand, built in China or Japan, a Tein is a Tein.

Even still, TEIN's dampers don't typically exhibit the "crosstalk" he claimed they do.

Every single Tein I dynoed did. That doesn't mean that every single one will, and there's nothing to stop Tein (or JIC or HKS or Zeal or whatever the flavor of the month is) from getting their act together and building a decent shock.

But past performance is not on their side.

So what? That means if you are at all serious about your shocks, you must get YOUR shocks dynoed.

If you find a flavor-of-the-month that, once dynoed, is proved to be a workable shock - hey, good for you. Awesome. Money well spent.

The point of the article - that ever so many fanboys miss - is not "Brand X Sux0rs and anybody who buys them is lam3" but rather "There is a metric assload of crap out there so you need to test EVERYTHING".

Buying ANY shock undynoed is a total crapshoot. Even shocks from my "good guy list" are not sure things. I know of at least one Penske vendor who habitually mis-assembled or outright damaged his shocks.... (Not Joe Stimola - Joe is good people)

C) JIC, TEIN, Cusco, Zeal, HKS -- all offer custom valving on their mid-upper level coilovers. Zeal will provide shock dynos (not sure about the others). Just because he can't get the parts doesn't mean its not possible

If it doesn't come with a dyno sheet, don't be so sure. One of the sets of a "famous Japanese brand" shocks I dynoed were supposedly revalved, but they exactly matched a second set of off-the-shelf shocks sourced from another vendor.

The lack of accountability, given that nobody was dynoing anything, means that there have been some pretty shady things going on in shock absorber land.

The other dubious claim is that no one needs adjustable dampeners.

DAMPERS. A "dampener" is a hose.

The "since F1 cars don't need x, you don't need it either" psuedologic is so played out. F1 teams don't need adjustable dampers because they have testing days where they can try out various custom valving. There is no need to have the extra weight of adjustable valving on the car because by the time the race starts, they know where they want the valving to be. This is in addition to a whole host of other suspension adjustments at their fingers, to fine tune throughout the course of the race.

F1 guys do their shock development on the 7-post simulation rig. They can play engineering curves (like frequency sweeps) and recorded data (from previous sessions) directly through the car and measure the response. They get the damping curves figured out well before the car ever reaches the track - and that shock has no adjusters because they don't want (or need) the weight and complexity on the car.

Yes, they have access to far, far better testing and design facilities than mere mortals.

But here's what you're missing - if it starts to rain mid-race, they change tires but not shocks and the car works just fine.

Get the damping right, and you never need a knob.

I had far, far better results with my car (and those of my customers) with properly-valved, non-adjustables than with low to mid range adjustables. High-end adjustables (Penskes) were great, but 80% of the use of the adjusters were fine-tuning on the dyno.

If we were twiddling knobs at the event, something was SERIOUSLY wrong.

Most guys at an autocross or track day have very limited suspension adjustments at their disposal. They can adjust tire pressure, they can adjust shock dampening, and they may have an adjustable swaybar. They aren't sitting there in the pits revalving shocks and swapping springs. They aren't adjusting the roll center. They aren't changing the alignment. They aren't changing tire size/compounds. So they have to make do with things that aren't ideal, but are better than nothing...

The fast ones ARE changing springs, alignments, roll centres etc. Not so much at the event, because all that work was done at the test session prior to the event. Just because you don't see it doesn't mean it isn't happening.

My ratio of testing time to race time was something like 100:1. A test weekend could consume multiple sets of tires, involve spring changes, bar changes, shock changes (usually in concert with spring changes, but also to test new valvings) alignment changes... you name it.

And then we'd go to the event and not change the car except maybe a tire pressure tweak. And it would WORK.

* The guy with $800 to spend who wants the best handling he can buy (even if at the expense of comfort)

This guy needs TIRES. He'll get way, way more performance out of a bone stock suspension and good tires than any crappy shock.

If body roll is an issue (as is likely with good tires), roll bars can help quite a bit.

* The guy with $2000 to spend who needs adjustability (either because he uses the same suspension to drive on poor quality roads that he uses on track days, or because he needs to dial in his car for each course he comes across)

This guy doesn't exist. Get the shocks right, and the car is not at all uncomfortable. Even with spring rates in the 2.5 Hz range, the car will transmit road noise, you will get feedback from every ripple in the road, but the car will not be at all harsh or uncomfortable.

As a test, I drove my full race setup flat-out on a dirt road (I changed tires to street tires to keep from flinging gravel all over the place, but otherwise, same setup) and the car did not back, buck, or beat me up. It just worked

The Pike's Peak guys do the same thing. That road is paved about 1/3 of the way and is dirt the rest. Same setup on both dirt and pavement. Admittedly not optimized for both surfaces (dirt wants less spring) but perfectly workable.

If you have $2000 handy and you want to invest in a really effective suspension, doing the work to tune a non-adjustable Bilstein is by far the best bang-for-buck suspension option. No question about it.

DG

http://farnorthracing.com

 

[Cz.]

If you're still here, any recommendation on who to send Bilsteins to for revalving?
I've found that there are a few places besides Bilstein themselves who do revalving, though they charge roughly double what Bilstein does. Not really sure if they're worth it though.

I read through your entire "autocross to win" section and I learned a lot of things, thanks for writting that up.

 

[RecceDG]

I'm a little out of the loop on the current state of who is doing what (in terms of services) as I just got back from Afghanistan.

I will say this though - once a Bilstein has been converted to a take-apart (which is admittedly a little pricey, as there is welding to do) subsequent revalves should be fairly cheap. It's simple enough to do yourself.

If you stick with Bilstein's published valvings, you can almost get away with not dynoing, as they will hit their force targets very accurately. The post-rebuild dyno is more about catching assembly errors (which do happen) more than confirming the valving.

If you are developing your own valving, you do need a post-assembly dyno, as changes in shimstacks produce non-intuitive changes in forces. There is quite a bit of trial and error.

But a whole shimstack is like $10. Bilstein parts are really very cheap - it's all labour.

When they fail, all you do is change the oil and a pair of seals - cheap. The bodies and shafts last forever. And even if you want a new shaft, that's like $25.

So that price hit you take up front gets you a user-serviceable part that will last forever.

DG