TRD shocks and springs

[NoHachi]

Hi jon,

I'm not making any judgement on the "quality" of these shocks. They look fine. The problem is that you can have very high quality shocks valved completely wrong for the application. Despite being high quality these would then return low ride quality and performance.

What springs can you match with a set of dampers..wel that depends on the types of damping curves that you dial in. Normally you want a digressive curve. Steep initial rise at lower speeds tapering of at higher speeds. The low and highspeed bits need to be set exactly right for your car. If succesfull you have a car that is controlled at speed and comfy during cruise (or at least as comfy as your springs allow). For an idea of how a digressive curve looks, take a look at the red line in the dyno's from my link.

Linear dampers like HTS are a compromise. They do not taper of at high speeds, so you are given a choice (if enough adjustment is available).
*Do I set the low speed portion right for the fast stuff (steep curve)? If so then the high speed part will overshoot and make the car lose traction over bumps and become more uncomfortable.
*Do I set the high speed damping correct and accept that the low speed section is suboptimal for body control? The car will be comfier during my commute, but I give up some body control.
Both these compromises are decent:
* Set high speed ok for track duty: optimal control and smooth tracks don't need much in the way of control over bumps or comfort.
* Set low speed ok and comfort is ok, but control less so. Not a problem since we are not introducing big forces into the chassis during DD anyway.

Digressive dampers can change exactly in tune with your suspension. This is a very delicate proces and takes some nifty adjustment hardware. Hence the huge prices of quality stuff like öhlins, Moton or Penske (notice that there are no AE86 manufacturers in that list..nobody loves us yet )

Then you have progressive dampers.. I'm sure that there is a situation in which progressive stuff is nice to have. I guess I just haven't heard of it. You have too little damping at low speeds to control chassis movement, but too much of it at high speed to be able to provide traction and control.

Now take a look at the dyno curves. At the lowest settings the BC's start of progressive.. This makes those setting essentially suboptimal, you'll always have underdamped body control or pay the price with a very stiff ride and poor grip (dorifto!).
In the middle setting they are linear.. So probably ok for track with 8kg springs, but could be better. If look at the red line for 8kg/mm (the rears of a subie) and forget about weight (ballpark ok) then you'll see that the mid-settings come out relatively ok for the low speed bit.
At high speed they are progressive...so slap these babies on a car that has stiff springs and they'll work a lot better. This includes cars with high motion ratio's like MX5's, Honda's en other non-McPherson strut cars..

Whew..lots of text..and still no idea what the 86 stuff really looks like. So you can probably ignore most of what I said. The 86 hardware is probably very different from the double adjustable stuff.