So I decided the car could use a suspension upgrade...

I was thinking about Tecna at first, but that evolved into a much bigger project in the course of planning.
A phone call to 949 pretty much steered me away from anything they could offer. You could chalk it up to the fact that ridiculing a customer is not the best method of instilling confidence and loyalty in a business establishment.

Anyway.. I made a plan.

I would get/make and install the following:

• Tein Street Advance coilovers
• RB 54103 hollow FSB
• MSM 14mm RSB
• Handmade endlinks for the sway bars
• Handmade support/reinforcement blocks for the RB FSB
• Aaaaand, Tein EDFC Active Pro thingie...

I then called Bryan at FAB9. He helped me immensely. We talked about this and that, and I placed my orders.

Problem: I live on the other side of the planet. That means eleventy billion dollars for shipping an item as large as a coilover box.

A friend was fool enough to post about his upcoming trip to Istanbul. I immediately threatened him with waterboarding his family, and convinced him to be my mule. He had to agree.

So, this thing arrived at the airport with my friend under it:

 

I proceeded to install just the coilovers and the endlinks I made.



I used heim joints with brass bearings (they have grease zerks), had my favorite machine shop make long adjustment nuts with rhd and lhd threads, used locking nuts, and most important of all, made a bunch of spacers and conical washers to prevent binding and ensure correct geometry. I also used heavy grade bolts with conical heads.
I spent 10 bucks and had everything chrome plated to avoid rust once and for all.



Installing the coilovers and setting the ride height took a whole the day. I had to make trips to the basement garage of a grocery store a few times to settle the suspension and take precise height measurements.

I adjusted the endlinks, and everything was just fine up to that point.

 

Some of you may wonder why I went with the EDFC ACtive Pro...

The thing costs almost a grand, sounds gimmicky, and introduces more potential failure points in the equation, right?

Wrong.

I researched this thing and found nothing less than glorious reviews from actual users. There are not a whole lot of actual users out there, because this is a pretty new product. Comparing this setup the the ordinary EDFC we all know and fail to justify is a pretty moot affair; it's like apples and unicorn tinkle.
(That IS the correct use of a semi colon, Joe)

It is expensive, tho. In the US, that is.
I found a cute little outfit in Japan, owned by a couple of Americans.
Click for awesome prices from Japan - Yay JDM!

So, that price came down, about halfway down with those guys.

And it was something I was looking forward to.
I mean, I faced the MS in the face, in all my noobery, and came out on top..
I wasn't about to shy away from programming a friggin' suspension doodad. It's not like I would blow the engine, or eject myself from the car if I got it wrong the first time around.

I respectfully asked my wife if it was OK to spend some dough on some toy that I wanted just because, and she said yes.

Protip: Always ask questions of this nature AFTER you do the dishes, wash, dry and fold the laundry, and clean the house, including the windows. Do not miss the windows. And wear pants while you do these chores, so the wife knows who wears them.

I talked to Bryan one more time and found out that the swaybars were on the way.

 

Installing the motors of the EDFC kit on the shocks would be a challenge.

Fronts are no big deal, there are no space restrictions under the hood.



All you have to do is remove the hex nut along with the knurled adjuster + the small piece inside the shock shaft, and pop the motor on.



There's youtube video by Tein on this, too:


The rears, on the other hand, were a different matter...

 

The "holes" on both sides of the gas tank are taken up by my water injection tanks.





Installing the stepper motors on the shocks would be impossible with those tanks in place. I also did not want to let go of my water injection system.

So I came up with a solution.

I would reshape the tanks, and add a third one in between to make up for the lost volume to make room for the motors.

And, I decided to go with stainless steel once I cut into the aluminum tank and saw the corrosion in there.

The tanks in the pics are Version 2. Version 3 were all aluminum.


I made a bunch of foamboard mock-ups and test fit the tanks.



I even considered installing a total of 4 tanks at one point. The fourth tank would go just in front of the gas tank. That idea was scratched.

 

The rear tanks proved more than adequate in the end.
All stainless steel, sight gauge for water level, and room for the stepper motors...



Total volume: 16 liters. Enough for a few days.
Stainless steel is expensive. Cost me about $200 to get them cut, bent and welded, including all fittings.

I also took the time to install the AEM failsafe monitor that was patiently waiting for its turn in a box on the shelf..

 

With the center tank in place, trunk carpeting was pretty much useless.
The solution was covering it up with 3mm MDF, and using self sticking auto carpeting to finish it off.



That's my tea "cup" in the trunk. You can see the water level sight off to the right side.

And, here's a close up of the sight glass opening:

 

The EDFC unit uses wireless modules, and that makes life easier.
I stuck one on the passenger side water tank in the rear, and the front module went on the actual firewall.
They work perfectly.

 

Here's what the controller looks like.
I opted for the GPS unit, it's also receiving the VSS from the ECU.

 

The unit takes the initial shock settings as base value, and adds or subtracts "stifness" from that setting based on speed and G loads.

I used the default settings for a few days to get a feel for it, and then made a few changes to the speed portion only.

Rears go softer up to 40 mph or so, and then stiffen up progressively. That made the car incredibly comfortable, especially in my 640 year old, cobble stone neighborhood.

G forces require dedicated time and a place with slow and high speed corners to get a feel for over and understeer. So far, default settings on the G actuated controls are just fine.

The car behaves very, very different compared to before. Seems to cling to the road, and does not let go. I found myself increasing my speed in familiar corners, and it is actually a lot of fun.
I sometimes peek at the gauge as I enter a corner, and all four values change in an instant. The manual says it takes 26 ms for a change. Outside shocks stiffen up, the front gets harder than the rear, and the car just holds its line.
Bumps and undulations are a nonissue. Soaks them up.
I no longer "crash" into potholes.
It feels like I'm putting on a different suspension on every piece of new road, and the car behaves perfectly.

Street Advance coilovers have 16 settings. Since you remove the adjusters to install the motors, you get to choose what setting parameters you would like. The motors give you a 16, 32 or 64 setting possibility. I used the 32 step adjustment range.

I mean, the car is PLUSH comfortable at slow speeds, and gets right down to business as the speed gets higher.

Plus, I now have a very accurate clock in the car...

 

Here's the pass side motor on the front shock.

It's pretty crowded in there.

 

Installing the swaybars was a pretty straightforward deal.
I already had the proper endlinks, and I decided to spend the $3 and get myself a couple of aluminum blocks to reinforce the mounts.

I have a pretty basic drill press, too.

 

And, the rear swaybar..

 

I feel like I should mention the Delrin bushings..

From what I have read so far, rubber CA bushings add about 1 Kg/mm of force to the overall spring rate.

Since I switched all my rear bushings to Delrin, that rate is effectively reduced to zero, meaning, I can move the entire rear suspension (without the shock and spring installed) from lock to lock with my left pinkie.
I'm pretty sure it has an effect on the coilover's, as well as the overall spring rate.

So, I guess it would be safe to say I have a 7/5 Kg setup, rather than the advertised 7/6. That may be contributing to the cushy comfort the car has found with this setup.

On a final note, I would never believe a light car like the Miata would become more comfortable with stiffer springs. I guess we live and learn.

 

Thanks for the detailed writeup and review. It's a brave new world out there with all these semi-active suspension systems including the EDFC Active Pro and HVT Tractive ACE.

 

Awesome!

 

Yes very nice, slick setup there.

 

Any updates? Do you still like them? Have they been reliable? I'm thinking about the EDFC Active Pro for another car (Infiniti G37) but have found very few reviews from actual users.

 

Yes, I still like the setup very much.
No problems whatsoever so far - aside from a curious car wash attendant fiddling with the settings and reverting the setup to default, which I immediately felt and corrected in about 30 seconds.
The car feels very good, and very planted under all conditions.

I'd do it again in a heartbeat.

Disclaimer: You need to spend some time to set it up properly in the beginning. Also, allow yourself at least a week of taking mental and written notes to make the necessary minor corrections on your speed and G load settings.

 

I can't believe I missed this thread.
And the whole EDFC active pro thing.

Do your shock ***** stiffen only rebound or both rebound and bump?
Because I think the best EDFC application would be to adjust *only rebound*. I think you would want rebound to stiffen on the *inside* wheels in cornering, so that the inside of the car will jack down - i.e. won't lift so much. This reduces body roll, and lowers CG. This also reduces oversteer when powering out of corners.

I remember an article years ago in Sport Compact Car magazine. They did a skidpad test on a car with adjustable dampers. Then they cranked up the rebound on the inside wheels. The car gained about 0.02 or 0.03g.

Then you can reduce rear end lift by cranking up rear rebound during braking, and reduce front end lift during acceleration by cranking up front rebound during acceleration.

Can you put a "tune" into the controller using a laptop? Can you map the **** settings as a 3D function of the 2 axes (longitudinal and cornering g's? (like having MAP and RPM as axes)