Rear strut tower questions
 

i tried searching with no luck, im in the middle of transferring all my good parts from my vert into my new coupe. i am trying to keep the interior as complete as possible but if i have to mod the rear strut towers to make my parts work then so be it. i want to know how people get access to adjust their coil-overs and install a rear strut tower brace in a coupe? also what people do for rear speakers?

:/ You have to cut holes in the the side carpet and body to get a rear strut bar installed..

I've seen people just eliminate the whole speaker mount from the strut, I just cut a square large enough to fit the bar in and a tiny hole in the carpet big enough for the bar to fit through, took ends off bar, slid carpet onto bar the bolted ends on bar and bolted bar into car and re installed the carpet.

To adjust the coils, I just took out all 7 screws and there it was. I think 99% of people don't adjust their suspension after the first week. The exception is at a track and you can just leave everything off. There are two types of rear bar, one is described above and needs a hole in the metal. The other is he mazdaspeed style that bolts to the inside and outside of the strut tower. You cut slits in the carpet for the bar mount. It is slightly less invasive. For rear speakers, you can fit a 6.5" speaker in the tower and clear both types of bars.

not quite related, but still.... i have a Cusco rear tower brace and like mentioned before i had to cut the sheet metal of the towers and also cut small holes into the carpet to fit the bar. i run KYB AGX's tough so adjustment is hella because it's near the bottom of the shock, not the top.

I bought a mazdapeed knockoff from e-bay. It does not require any drilling of the speaker mounts, as there is already holes in the speaker tower. You need to drill through the carpet for some small bolts though. If you don't mind the knockoff (which is as good as the "real" one.) It's about 100 shipped.

very true Rxspeed16, i hardly ever adjust my coilovers but i was just seeing if there was an alternative option but leaving the speaker and everything up top is just a sacrifice ill have to make. Does anyone have pictures of the rear strut bar installed and pictures from inside the speaker mount so i can check out the holes people have hacked. and i have the corksport strut bars btw.

I am in that 99% and only change the coilovers during track days (5x a year at most), mostly to try different things, not lowering my lap times. As for getting to the adjuster, some have removed the speaker, but left the cover on. Then they put a small hole in the cover grill, directly above the adjustment mechanism. As long as it's large enough for the adjusting tool, you can just reach straight down without removing anything. Or if you're really fancy, you can get a remote control, http://www.tein.com/products/edfc.html

dont need speakers with the sound of a rotary

I ran coilovers that adjusted at the top of the shock,and I attached the speakers to the Covers with screws and nuts(right through the grill then painted the screw tops so you wouldn't notice),then just put 2 screws in the covers so you could unscrew it, and take the speaker/cover assembly off as one.
and NO TUNES??..holy shit!..Unless I decide to go on Track 24/7 I am keeping Tunes in my car!.
(Put on a REAL good tune and go for a run..nothing like it,,pure S-E-X!)

for strut bars
https://www.rx7club.com/2nd-generation-non-technical-pictures-198/pic-request-tc-sportline-rear-strut-bar-809380/

no need to cut anything except for the carpets.
As for coilovers you can just take out the speakers everytime you want to adjust the setting. Its a hassle but for me, I cant have just teh front speaker putting out tunes lol

I tried the remote adjusters for my Stance coilovers and the first time I tried to adjust the damping down the crimps on the knobs failed. It was a good idea and horrible execution.

All they had to do was put something inside the spring where they crimped the knob on to keep the spring from unwinding out of the crimp and it would have worked.

I will try complaining and hopefully they update their design.

For now I just have my speakers held in by gravity and the speaker covers held on with the plastic fuzzy shafted rivets in the 2 spots in the top of the covers so I can rip it all out fast for adjustments.

Personally, I don't think rear bars do anything for the FC other than add weight. The loading on the shock mount is completely vertical, and the car is pretty well structured in that regard to begin with.

+1. This point doesn't get mentioned enuf. Structurally, there is absolutely no reason to use a rear strut tower bar on a FC. Similar situation for using the strut tower location as a roll bar mounting point, better to tie into the boxed floor structure. A rear STB can be used a poor substitute for a harness bar though.

To help the OP, you can mount a small speaker box between the rear towers for decent sound. Saw a good example at 7Stock, but it was all black so the pic didn't turn out. :uh:

Personally, I don't think rear bars do anything for the FC other than add weight. The loading on the shock mount is completely vertical, and the car is pretty well structured in that regard to begin with.

+1. This point doesn't get mentioned enuf. Structurally, there is absolutely no reason to use a rear strut tower bar on a FC. Similar situation for using the strut tower location as a roll bar mounting point, better to tie into the boxed floor structure. A rear STB can be used a poor substitute for a harness bar though.

The rear "strut" bar does a huge amount of good on an FC because of the large open area in the unibody for the hatch which allows the unibody to flex.

It isn't supporting a strut from moving as the name might imply (as you stated it is on top of a shock mount with no horizontal suspension load placed on it), but a bar across this area does help reinforce the chassis and the difference can be felt.

The rear bar location on an FC is superior to bolting your harness to the floor because it results in a much better angle on the harness as it passes through the seat and over the shoulder. However, the rear bar must be properly designed to handle the forces- for instance I would not trust my JIC CF bar as CF splinters instead of deforming as a mild steel bar would.

OK, fair point that there is a large open area for the hatch, the question is, do the rear suspension loads distort the rear unibody structure enough that a rear strut bar significantly counteracts those deflections. I say not really, but frankly have no data to back it up.

You appear willing to concede that the shock loads are not causing the top of the towers to pinch-in or expand apart significantly, so we are left with torsional deflection (twisting) due to the subframe loads acting on the chassis. A rear strut bar could certainly help counteract this twisting if it were happening. One way to test it is to replace the bolt tying the crossbar to the mounting bracket with a wooden dowel. If the deflections were substantial as you claim, that weak pin would snap. Give it a shot.

Totally agree with your clarification here, that's what I meant by "poor substitute for a harness bar". Since the brackets for your JIC STB are aluminum, it could possibly still work as a harness bar since they might bend before the CF strut snaps. I doubt you want to test this theory. :egrin: Um...what was this thread about again?

Appreciate your comments regardless.