Flyin' Miata Cannon rear subframe brace

First off, this is a really high-quality part. Well engineered and built. Looks fantastic. I can't really say I noticed a huge difference after install though. I suspect this is because a) I had already put a lot of extra bracing on my car (butterfly brace, strong arms) and b) I have an NB2, which is already the stiffest chassis of the early generations.

If you have an NA car, I'd guess this has a much more dramatic impact on your rear-end stability and predictability. And in any case, as said, it is super high-quality.

I bought this knowing the frame rails and butterfly bracing were going on too. This went on first. Was it a huge difference on its own? No.

Add the frame rails, butterfly brace, already installed rollbar...and the car is getting there. This likely solves a next available weakness issue. The car was already flexing, add the frame rails, and the unbraced (1990) rear becomes the next point of "failure". Add this brace, and the rear gets stabilized, and the flex point gets pushed to the springs and mounts, where it should be.

Overall, I feel confident it is doing something, but have no way to quantify that. And since I gave myself a blood blister putting it on (needed little encouragement because I didn't read the directions well enough, do not tighten the over exhaust piece before it is all mounted), I am not taking it off to test that theory.

I mounted it on a 97’, grinding the factory brace mounts off took just a few minutes and installing the cannon brace was straightforward and quick. The coating flakes off a bit but as it is an aluminum brace it doesn’t matter. The difference in handling was immediately noticeable with the car rotating through corners a lot better. I actually had to put the my front sway bar on a stiffer setting to compensate for the extra rear end input. It does seem that under impacts where only one rear wheel hits an obstacle eg. a pothole the car will upset more than normal but during regular driving conditions it is more composed.

I mounted it on a 97�, grinding the factory brace mounts off took just a few minutes and installing the cannon brace was straightforward and quick. The coating flakes off a bit but as it is an aluminum brace it doesn�t matter. The difference in handling was immediately noticeable with the car rotating through corners a lot better. I actually had to put the my front sway bar on a stiffer setting to compensate for the extra rear end input. It does seem that under impacts where only one rear wheel hits an obstacle eg. a pothole the car will upset more than normal but during regular driving conditions it is more composed.

Don't listen to them. Don't use a torque wrench at 20lbs. Hand tighten only snug. They will snap before 20lbs with a torque wrench. Now I have to remove everything to drill it out. Also on an NB this brace is totally obsolete so really not worth it and they should tell you that. We have a bar running across right under where this goes. So this does jack all. Except fudge your $130 flying Miata alignment and break some bolts. For NB owner the juice ain't worth the squeeze. I hope they change the directions. Hand tight just snug.

Note from FM: 20 lb-ft is the factory torque spec for the studs here, as per the factory manual. We use these same specs for sway bar installation instructions and have for several decades. It might be worth checking the calibration of this wrench.
The factory bar does tie the two lower points together but it does not triangulate them to the upper points, which is not as effective.