Well after waiting almost five months my AutoExe Member Brace arrived from Japan. I ordered it from HERE it cost $603 plus shipping. This mod has arguments both for and against. Since the installation involves just replacing the OEM member brace component with the beefier & more encompassing AutoExe parts it would seem Mazda thought the car needs some form of frame bracing. This is an easy install on most 8’s done with basic hand tools. Please hold any replies till I am done posting.

Tools Needed:
Jack Stands / Ramps
12mm, 17mm, 19mm Sockets 1/2" drive recommended.
Torque Wrench that can go up to 115 ft lbs.
Might need a hacksaw / grinding wheel.

Photos:
1 & 2 the included instructions.
3, Show the OEM braces that you need to remove.
4, Shows ground clearance BEFORE install.
5, Is the AutoExe Brace.

 

Photo one shows the front OEM brace and the bracket mentioned in the second AutoExe instruction sheet. Please remove the three bolts on each side. They might be tight so use a long handled socket wrench or breaker bar. Those bolts also have DIFFERENT torque specifications so using a torque wrench to re-install is important. Once you remove the OEM brace test fit the AutoExe Brace. If the brace will not fit flush against body do to interference from the bracket circled you will have to remove that bracket and remove enough of the lip for the brace to fit flush. The Included instruction provides a liberal template. I however did not need to remove it as there was about a 1/4" of space in-between the AutoExe brace & that bracket as seen in photo two.

 

Photo one is important; bolts 1-3 are the OEM bolts and are re-used with the AutoExe Brace. The circled bolt, (photo two) washer, lock-washer comes with the brace along with a small “L” bracket that has a nut welded to the straight end. The RX-8 doesn’t have a nut for that bolt in that area of the frame. What the “L” bracket does is hold the nut and bolt in place and there is a hole in the frame that might be covered with factory undercoating. The nut will fit into that opening into the frame once tightened. You might need to jiggle the brace to fit both of those rear nuts into the frame holes so only hand tighten the bolts at this time.
Using a torque wrench I alternated tightening the bolts left / right side of car. I did this to make sure the brace “seated” properly. The torque settings are as follows.

Bolt, 1 86-115 ft lbs.
Bolt, 2 72-94 ft lbs.
Bolt, 3 58-76 ft lbs.

The rear bolt (the one provided by AutoExe) just needs to be tightened enough to compress the lock washer.

 

Installing the rear portion of the brace is also easy. The AutoExe brace replaces the OEM braces in photo one (did not take that photo) and ties that area of the frame with the rear suspension. To install the rest of it you need to remove the circled bolts in photo two. One bolt is next to the fuel tank in a part called the “stopper plate”; the other is in the lower rear-trailing link (photo three).

 

Once the parts / bolts have been removed begin by installing the square brace to the body by re-using bolts #1 (photo two). After you figure out which rear brace is left / right attach them to the rear suspension by re-using bolts 3 & 4. Then place the top part of the triangle brace into the recessed rear section of the square brace and hand tighten bolt #2.
Again alternating the tightening of the bolts the torque specs are as follows. Also be sure to jack the rear high, tightening bolt 4 might be hard with a long handled torque wrench.

Bolt, 1 14-19 ft lbs.
Bolt, 2 13-19 ft lbs.
Bolt, 3 46-68 ft lbs.
Bolt, 4 55-75 ft lbs.

 

That’s it, lower the car and go for a ride. If you torqued everything correctly you shouldn’t hear any strange sounds. I would also re-check the torque after a few hundred miles. It’s kind of hard to notice any improvement driving around the neighborhood. With my other mods my 8 corners well already. My goal is to improve handling without changing the shocks/springs. I like the ride and do not wish to change that. I also do not wish to lower the car or go through the install process of springs. I hope this will be more noticed at the track. Along with the Brace I have Racing Beat sways, MazdaSpeed front & rear strut tower braces and will get 245/40/18’s if my RE040’s ever wear out. The weight of the brace is 22 Lbs. Minus the 7 Lbs of the OEM parts removed this brace will ADD 15 Lbs to your 8. This brace also doesn’t decrease the ground clearance much. The photos attached are of the completed installation.

 

Hi SpongeBob,

Congratulations on your successful installation of the Autoexe braces. Nice pics! Great and well organized instructions!

I have the same thinking as you. I love the stock suspension and civilised ride and would not want to change the coilovers. I have installed Carbing front tower brace. May next project would be the anti-roll bars or sways as you call it. Questions :

- Would sways have an impact on the ride quality? I believe it should be none or minimal
- Would sways add to the body rigidity, almost acting as an extra brace?
- Which is better, solid or tubular sway bars?

Thanks for your comments.

-Ringer-

 

i am envious! plz post in the suspension thread after u drive it hard and tell us ur impression!

 

Check out the RB Sway Bar Install DIY. Here's my evalutation from that thread:

"Finally got my RB sway bars and installed them today. Installation was not difficult. Only thing that was a PIA was snaking the original front bar out and the new one in. The rear bar installation was a piece of cake. Entire project took about 2.5 hours including jacking up the car, removing the wheels, and other preps.

The instructions that came with the bars were pretty good, although they could stand some improvements, particularly larger/better pictures to go with the instructions. The pictures included were pretty small and in some cases it was difficult to make out the details referred to in the instructions. I also printed out and reviewed the original DIY posted in this thread by expo1. That was definitely helpful also. The shop manual was not much help since it assumed that the large plastic pan under the front of the car was not there. I wasn't about to take off that pan.

I took a short run through the twisties in the mountains near me after installation and had the following impressions:

**Steering was noticably more precise. It was already precise/tight, but now it is REALLY so. And the turn-in-point/apex relationship definitely felt different. The slightest movement of the steering wheel translated immediately into a change in direction. Seemed as though I needed to be more focused on driving to keep from drifting out of the travel lane.

**Most of the minor body roll previously experienced during heavy cornering is gone. I said MOST, not ALL, but it is much improved. Installation of certain aftermarket springs would likely eliminate nealy all of the body roll, but I'm not willing to give up more ride comfort for the last little bit of body roll. Now I need to think about 4/5-point racing harness to keep me in the seat when cornering. (Note to self: Gotta think about mounting options for such a belt.)

**Ride was slightly harsher but not objectionably so. It seemed to me that small bumps/ripples in the road that I didn't notice before are now noticable. Might just be my senses being more acute to such things because of the desire to feel the difference in ride after installing the bars.

All-in-all, I am pleased with the handling and the feel of the car with the RB bars installed. It's about what I expected so that's all I can ask. It was money well spent in my opinion."

 

Go48 answered most of your questions, here are some other threads that might help you.

https://www.rx8club.com/series-i-wheels-tires-brakes-suspension-55/sway-bars-50941/
https://www.rx8club.com/series-i-do-yourself-forum-73/diy-racing-beat-sway-bar-install-43677/
https://www.rx8club.com/series-i-wheels-tires-brakes-suspension-55/swaybars-racingbeat-vs-whiteline-53509/
https://www.rx8club.com/series-i-wheels-tires-brakes-suspension-55/front-sway-bars-questions-44950/
https://www.rx8club.com/series-i-wheels-tires-brakes-suspension-55/tanabe-rb-sway-bars-24298/

 

nice installl
looks good man

 

please post your impressions after you drive it hard

 

That will happen 6/4 @ Summit Point Raceway. One thing I have noticed is on real bad roads (Brooklyn, NY) I feel more of the road imperfections than before but I think that is just because the about of flex has been reduced. On normal to “OK” roads the ride is fine.

 

good i was thinking about this as well as autoexe's own 4pt front and rear strut set with JIC FLT-A2 coilovers, and the racing beat sway bars and rear endlinks maybe with some cusco pillowball suspension pieces.(with the 2 pc 4pt struts, both front and rear anti sway bars, sport shocks and springs, and 4pc lower arm brace set you'd be fully autoexe suspension'ed out) :D

putting handling mods on a point and shoot car seems moot but i wont stop untill it handles like a mini cooper S.

 

you will feel every pebble with those mods

 

im 16, the last thing im concerned about is the condition of my back and ride quality.

 

That's what they all say. I was 16 not too long ago and driving a car with those mods as a daily driver will make your car a rattle disaster. Trust me, been there done that. Feel free to do whatever you wish, just know that Darkmaz8 told ya so.

 

who said it was a daily driver? it gets about 3 miles per week between my dad and I

 

i would imagine these are not legal in scca solo2 STU? i mean, i hope they are but probly not

 

expo, any updates on how the car feels with them? I know it's been awhile, but I'd like to know the difference with them on.

 

Car handles fine. I would say that on the street you might not notice it. But I track my car and I am happy with the way it runs on the track.

 

its a very track oriented product so you'd expect that. i dont see what the point of spending 600 dollars on reinforcing your frame that you don't put through 80% of its stress threshold by just driving it on the street

 

Definitely.

 

You make some very valid points. But I had some money to put into this car and after spending alot of time on this board I thought the best place to spend money was on suspension mods and track time. After four trips to Watkins Glen I am happy with the way I modded my car.

 

wow that was suprising considering the person that doesnt even touch cars anymore actually said something that makes sense...im probably more suprised just because im baked.