Flyin' Miata butterfly brace v2.1 upgrade
Flyin' Miata butterfly brace v2.1 upgrade
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Description
Note: This kit allows you to upgrade your v2.0 FM frame rails to the full butterfly specification. It is not compatible with the older frame rails. It cannot be mounted to a car without a set of frame rails.
If you don't already have a set of v2.0 frame rails, you're looking for the full butterfly brace.
The butterfly brace "closes the box" for improved chassis rigidity.
First, why do you want chassis rigidity? Because a stiff structure allows the suspension to work better. If your chassis flexes, it's basically a big undamped spring that changes your suspension geometry under load and shudders every time you hit a bump. A stiff chassis will give your suspension a solid platform to work from, leading to better, more predictable handling as well as improved ride quality. There really is no downside. Chassis stiffness is usually measured as torsional rigidity - resistance to twist - because that's how loads usually travel through a car.
When it came time to update the design of our popular and effective butterfly brace, we did it properly. We tested Miatas in a variety of configurations, from a high mileage 1990 to a late NB with the full Sport bracing. Here are some of the highlights:
- The new design is stiffer than the original design
- The new design ties right into the front subframe mount points
- Fuel/brake lines have more room than with the original design
- The new design fits a wider range of cars and exhausts
- The new design includes mounting points for attaching a flat undertray (not currently available)
- The new design is dramatically easier to install and remove for service.
Ground clearance is unchanged from the factory Sport bracing. The new design gives more clearance for various exhaust configurations and is easier to remove if you need to do work like dropping the trans. It's fully compatible with factory front and rear subframe braces. Cars with the "Sport" undercar bracing will have to remove two cross braces in the center. It's made of stainless steel so there is no concern about rust. The butterfly upgrade adds 19.5 lbs to the car, low and in the center of the car.
The butterfly brace upgrade adds the center section to an existing set of 2.0 frame rails. If you have our older frame rails then they're unfortunately not directly compatible without welding in some mounting plates.
The differences between the 2.0 and 2.1 butterfly brace designs are minor, and they are interchangable. The primary modifications have been for more consistent quality.
Stiffer. Easier to install. Lower price. Now that is progress.
Miatas with stock headers will likely need to cut the heat shielding off to prevent interference. This is a relatively easy modification.
Instructions
Shipping
What does it fit?
Fits: 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1999, 2000, 2001, 2002, 2003, 2004, 2004 MSM, 2005, 2005 MSM
Emissions
Emissions do not apply.
Warranty
1 year
SKU
I had added the V2 frame rails to my 1990 Miata a couple of years ago. That was a nice change. It made the car more stable on bumpy roads, less flexy and less bouncy. At least that made it feel like the car wasn't shaking itself apart when cornering quickly on rough pavement.
Now I have indulged in the V2 frame braces. As soon as I sat down in the car without even starting the motor, it felt quite a bit different. More solid, stiffer. I never perceived that it was flexing just by sitting in it. By the way, this car has 135k miles, but is in pretty good shape. No rust.
Coming out of my driveway, it was less wiggly and noisy. It feels more planted, and smoother. I almost want to say the manual steering feels heavier, but tighter at the same time. I think this is because a given amount of movement in the steering wheel is effecting a greater change of direction, and I think this is because before, the chassis was loading up like a spring. So the steering was spongy before, and is now is acting much more firmly on the car.
There is a highway ramp connecting one highway to another that I often traverse. This is a long corner with a slowly decreasing radius, a little less than smooth. In the past, even 65mph around that turn felt like I had to actively steer the car and hold it stable. Now, with the braces installed, I took that turn at 80+ and felt much more stable than before. I did not have to drive to the wiggle, keeping my hands loose as the wheel whipsawed in my hands. I was able to drive with much more confidence. I feel that I could take that turn at 100+ without an issue.
My opinion is that this bracing makes the chassis far more rigid and takes away almost all of the winding up and releasing oscillation that I felt before. This is a great upgrade that really makes the car feel smoother, tighter, more responsive and more stable. I am even more in love with this car now.
A worthwhile expense for a NA Miata. The car is more solid and stable. My car is a 35K mile car, and yes, what a difference it makes. I purchased the frame rails and installed them first. FM was out of stock on the butterfly braces at that time. I am glad that it worked out that way. I was able to experience the difference each one made.
When I first got my 99 in 2019, I almost immediately got a pair of the version 2.0 frame rails and installed them on the car. They made a nice difference, mostly, in that they added safe jacking points.
When I took my car out for the first time after installing the butterfly braces, the difference between rails only (plus Paco arms, diff brace, hard dog roll bar, and all the additional Mazda sport bracing they offered through the years) was amazing. I expected some additional rigidity and rattle minimization, but the difference in how the car feels was profound when I drove over the same potholes I drive over every day.
It feels like my car is 15 years newer in how it responds to expansion joints, bumps, and in general, overall stability. For the price, these are the single biggest improvement to my Midori I have installed to date.
I bought the frame rails when V2 was introduced but I did not do the Butterfly Braces until now.
Easy install, and the car feels even more stable and tight. Another great product as far as I am concerned. Not the cheapest but very effective.
I've been waiting for the butterfly brace to become available since I purchased my frame rails last year. As soon as I noticed the new version was available and in stock I placed my order.
Order was shipped right away, and received within 3 business days from my order. As soon as I received them, went to the garage to install them. The install video recommended using a jack to hold the braces up while installing, but I didnt find that to be needed. There is some heft to these, but it isnt unmanageable for a single person to do without additional help.
Everything lined up perfectly, as you'd expect with an FM-engineered part. All-in-all install took about 15mins once the car was on jackstands. Only issue I've experienced is the rear brace makes contact with my Roadstersport V3 catback, and the front brace contacts the heatsheild on my stock header. This is likely due to my original 27yr old exhaust hangers, so I've ordered polyurethane replacements to help.
First drive after install blew me away. Car feels much more solid when going over normal road bumps, cracks, dips, etc. Hard to quantify, but it was a noticable difference. Car just feels solid now. First track day of the season is coming up this weekend and I'm excited to see how the car performs compared to last season.
Buy these, you wont be disappointed.