JIC Coilover install on 2004 Mazda RX8 - How to - FAQ

How to install coilover suspension on your Mazda RX8, JIC coilovers in this example-

We hooked up with a pre-order of JIC coilovers so we are one of the first to install before the rest of the retail market on our RX8. The box arrived on 11/21/2003 from Brian at Good-Win Racing:

The first thing we noticed was that the spring rates were crossed out, and we got 1KG more than expected in the front..... we got 9/5 kg's, instead of the usdm 8/5's.

Here's a few pics before the install, click on an image to view it full screen:



We did the rears first as they are the most difficult to do on the RX8. Open the trunk, and remove the road wheels. In the trunk you will find some plastic screws that will have to be removed to get to the upper strut areas.



The first thing to do is remove the head light leveler arm, and the sway bar link, left rear side here

After that, remove the 14 mm upper bolts and lower bolts in the trunk. Afterwards, there is a 12 mm that you have to undo from the bottom of the car.

Then mark the inner rear link bar, we spray a bit of yellow paint here, and then scored it with a screwdriver to mark alignment for reassembly.

Remove the rear shock/spring assembly, and it will take a bit to undo.. Did you undo the sway bar links on both sides for easy prep? After that, transfer the upper cone assembly to the new coilovers. Positioning of the coilovers should be even for the rear for reference for install... but you will have to adjust them to approx height later, and then corner balance.

Now take the pre-assembled rear coilover and work it into the car. If you disconnected the sway bar on both sides, it should go up fairly easy, if not, do it now! Get it aligned and slip the bottom of the coilover on to the hub. Get a small jack, and put it under the lower hub and slowly jack it up so the upper threads go into the trunk.

Lock down the upper 14mm bolts and stay away from the lateral bolts for now. Don't impact, just hand tighten for now!!!




Simple as that! Now return the rear link and line up the marks, and torque all the bolts down

Repeat on the other side, and remember that the rears are the most difficult side! Use some locktite on all of the bolts and the rears are done!!!

So get those rears done, and don't worry about the height/preload at this time, as long as they were matched up before install on the rear pairs, getting the setup very close before corner balancing is going to be breeze! Put the wheels back on, then torque down the bolts in the trunk!

Remove the road wheel and pop the hood up. You will need to remove the front strut tie bar from the upper strut mounts. I think it's a 12 or 14 mm nut. Get that bar off and the 3 upper hat retaining nuts! Do not undo the center nut that holds the strut/spring together.


Look at the strut, and there's a lower 17 mm bolt. Remove it completely:

Remove the sensor line, a 12 mm if I remember correctly:

Next, let's work the assembly out. Grasp the lower end of the stock strut, and pull it outside. Then work the upper A arm, and you can lower the strut assembly. Then move the upper part out at the top and then with some manipulation, it will come right out after you clear the fender up top.

The angle of the driver's side (left) strut coming out after it's lowered:


Then put the new coilover in place, lower side first, then work it in, and look at the top side for clearance:

At this point, it should be self explanatory. Lock everything down in reverse order, use loctite if you can. Do the sway bars last after each side is done, and just jack a side up a bit to get things to align. Remember the stock sway bar links are plastic behind the ball joints, so use extreme caution! With the extended top adjusters of the JIC's we had to grind down some side metal with upper strut bar.

It's late, and the next step is to get the suspension close to where I like it in height, the next weekend: Corner balancing and performance alignment. Stay tuned for more progress on the RX8

Ok, after the JIC Coilovers were installed, there was no way to adjust them without taking the shock/spring assembly out of the car. We came up with a primative, yet VERY effective way to adjust the coilover dampning rate without undoing a single bolt!:

We started with 1/4" ID hose (acutally 6.35mm). We used Fuel Injection hose, because it is more durable and less prone to breaking if you twist it a lot. The install is pretty simple to do. Drop the coilover, lower bolt and upper retaining bolts, including the side brace. Don't forget the 12mm under the spring plate.

First of all, take the hose and a file, and ream the hose out a bit. You could probably use 3/8" hose and a hose clamp, but that was too big in diameter for our use. We squirted some silicon lube on the inside of the hose and routed through a top hole. Work the hose over the top of the dampner adjuster until it's over the knurled portion. Then use a zip tie or a metal clamp just to be sure!

Here's a few pics of the install, click on an image to view it full screen:

 Here you can see the hose sticking out, we cut it about 4" back, and are able to adjust the dampning on the fly!!!!

Overall, this is not a difficult mod, and you are better to do it during installation of the coilovers, or even when the koni shocks come out! The size might differ on the top of the adjuster, so take care to have plenty of supplies on hand, and do it right from the start!

We do have some more pics in the swankmonkey.com photo album here!

Posted in | Submitted by deviantspeed on Fri, 2006-11-17 03:57.
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