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Flyin' Miata NA/NB frame rail reinforcement kit

Flyin' Miata NA/NB frame rail reinforcement kit
Flyin' Miata NA/NB frame rail reinforcement kit

Increase your Miata`s stiffness by 30% with our stainless steel frame rail reinforcements. Make an old Miata better than new. $50 price drop!

Made in the USA

Exclusive to Flyin' Miata

Availability: In stock



Viagra for your Miata! A simple piece but a very effective one. These braces slide over the factory frame rails and stiffen the car dramatically. The factory rails are easily damaged over bumps and mistakes when jacking, and every time they are bent the car gets floppier. Our initial testing showed a 30% decrease in twist and the car feels far more solid when it's being driven. Subjectively, our original test car felt as stiff as a 2004 Mazdaspeed when equipped with these rails. Ground clearance is unaffected and the total added weight to the car is just under 13 lbs. The rails and the fasteners are 14 gauge stainless steel to prevent corrosion. They're strong enough to act as jacking points as well.
Since their original introduction years ago, we've been working to improve them. The fuel and brake lines are now mounded to welded studs. The number of holes for installation has almost doubled, and even the length of the bolts has been fine-tuned to improve clearance in a tight spot.  Not all the changes are obvious, but they make for a better product. We've managed to drop the price by $50 by negotiating better prices with the production facility as well.
To make your Miata even stiffer, we highly recommend our  butterfly brace upgrade as well.
No welding is required for installation although 24 holes need to be drilled in the car. Fits all 1990-2000 cars as well as the 2001-02 cars without the Sport bracing. Sport cars and 2003-05 Miatas can use the braces although one of the factory cross bars has to be removed. The factory bar can be retained with a slight modification. If your factory rails have been damaged, they may need some massaging with a hammer to allow these to slip over top.
 There are less expensive knock-offs out there.  None have all the features of our originals, though, such as stainless steel construction and the cutouts for lower weight. Also, the FM rails are the only ones compatible with the acclaimed  butterfly brace upgrade.

See an installation! One note about this video - the competitor product mentioned is made of mild steel with zinc coated fastners so it'll be less corrosion resistant than our stainless items. Also, these rails survived multiple end-over-end rollovers on a previous car, then got reused.

Additional Information

Additional Information

Part number 13-69010
TÜV approval available No
Fits: 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1999, 2000, 2001, 2002, 2003, 2004 (non-MSM), 2005 (non-MSM), MSM
Manufacturer Paco Motorsports
Flyin' Miata exclusive Yes
Fits Exocet? No
Proposition 65 Warning: Cancer and reproductive harm
California emissions No

Customer Reviews 13 item(s)

A must buy if you put a new suspension on your car
I put these on my 2000 NB after I had put on a set of Vmaxx coilovers and summer tires. Before I put the frame rail reinforcements on I was concerned with how loose the car felt with the new suspension. After I had put the frame rails on all of my concerns went away. Not only did my car feel tighter and more predictable in the corners but it was quieter and smoother driving normally down the road.

If you plan on putting a sport suspension on your car, you need to but these on your car in order to take full advantage of your cars new performance.
Review by Newwt / (Posted on 12/19/2017)
Every Single NA/NB Miata NEEDS These!!!
Simply put, EVERY SINGLE NA & NB NEEDS THESE! How much more eloquently can you put it.

I had a full butterfly / frame rail brace on my first NA, and just frame rails on my second NA, and these take decades off the car's age...making it feel like a NC or ND in terms of quality.
Review by Richard Dekker / (Posted on 9/11/2017)
Useful on an NB2
People talk about chassis flex on the miata, but seeing as how my 03 already came from the factory with a significant amount of underbody bracing, I doubted frame rails would do much. I pulled the trigger on a set anyway and I’m glad I did; these were a real eye opener to how floppy the miata is. It used to be that my midpipe flange would scrape the tallest portion of my driveway when entering/exiting. Now that the chassis can’t flex so much, my suspension does more of the work and the exhaust doesn’t scrape anymore. In high speed corners, I noticed that the grip and balance of the car were different than before and that I could carry more speed than I used to. Lesson: the less the chassis flexes, the more the suspension can do its job.
Keep in mind that these aren’t going to eliminate all chassis flex on their own and they most certainly will not cure your cowl shake either (‘less floppy’ and ‘stiff’ are two different things in this case), but they definitely do their job reinforcing the chassis where it is weakest and any NA or NB can benefit from a set.
Review by Steven / (Posted on 8/24/2017)
Great bang for the buck
Why is it the older I get the more help I need to stiffen things up? I'm getting a bit tired of writing this but -once again a great product from FM. Can't believe Mazda didn't do something similar during production. The stock frame rails are paper thin, doesn't even seem right to label them "frame" pieces. Installation on my 95 wasn't bad at all and I found $1.35 in change when I pulled the seats! The only thing I did do that wasn't in the instructions was to lift the car then put all 4 wheels on blocks so the "frame" would be in the same position as when wheels were on the ground. Didn't want to twist the body with the lift and bolt it all together out of wack.
Once installed the car has an overall more solid and well built feel, wish I could say the same for me.
Review by Swifty / (Posted on 8/4/2017)
Installation hassles
Installation of most aftermarket parts can be a nightmare, but I've found most Flyin' Miata stuff to be good quality....I'm a fan. Installation of the frame rail reinforcement into my 2003 NB was NOT fun. First of all, I have a brace toward the back of the car and I had to modify the frame rails in order to maintain the OEM brace in its place. My second complaint pertains to the fuel lines on the passenger side. The Flyin' Miata solution didn't work for me. My fuel lines could not stretch enough to modify the brackets according to instructions, so I spent a few hours modifying my own alternative. Finally, some of the right - inside bolts are located so as to interfere with the fuel line brackets. I spent a lot of time messing with that problem.

I installed the frame rails on two rainy days and didn't take the car out for an after installation test drive. So, after I take the car out, I might be wanting to write a rave review. I'm still glad that I bought them.
Review by Steve Littlefield / (Posted on 6/6/2017)
Noticeable difference
It makes a very noticeable difference. I enjoy it so much in fact that I want to buy every brace I can to solidify the structure. Despite the huge difference the rails make, it is still a convertible so it still vibrates and has cowl shake but not it takes bigger impacts to trigger the shake.

I'm very happy and highly recommend them.
Review by Jdiek / (Posted on 1/31/2017)
Buy these rails bro
Just put these on with a hand from a friend. BUY THEM. The car feels so much better. Potholes and rough roads are totally soaked up and the car feels at least ten years newer. If your thinking about the other guys frame rails remember that these have the butterfly brace that can be put in later, come with a sweet FM sticker, and look genuinely more BA than the competitors
Review by Brady / (Posted on 5/31/2016)
Who doesn't like a stiffer chassis?
Like you, I've read all the reviews and great things to say about these frame rails. However, I never rode in a Miata with them installed to make a comparison. After much research, I pulled the trigger on these and added the butterfly upgrade.

The install was straight forward and is quite easy with two people, one drilling from under the car, one above placing the nuts and bolts. You can actually see the floor pan get squeezed in a bit when you tighten the nuts. I sprayed some rubberized undercoating into the drilled holes and on top of the bolts. The butterfly piece takes a bit of fiddling to get it to fit, but it fits properly when you have everything else in place. Overall took about 4 hrs to do including removing and reinstalling interior pieces.

The difference is drastic. The chassis is tightened up and bumps are soaked up. What felt like a floppy chassis shake on my 15 yr old NB1 when going over bumps is now a solid "thud". Bumpy roads are still bumpy, but the feeling on the highway is also more composed.

I would definitely install these again if I had to.
Review by Mike / (Posted on 8/14/2015)
Huge difference in perceived rigidity/solidity
So... embarrassingly, I had these sitting in my garage for a long time before I got around to installing them (I ended up having a friend with a shop help out so we could use his lift). I haven't done any performance-oriented driving with them yet, so can't speak authoritatively about that aspect, but I can tell you that I had an immediate "WOW" moment when I drove the car home on the truck-damaged surface street between his shop and my home.

I'm always wary of confirmation bias in such a subjective review, but I've been driving this car for 25 years (since new), so I'm pretty familiar with how it shakes and rattles on bumpy roads, and there was a LOT less of that. I felt like more like driving my wife's new Audi down that road than my OLD miata. It was similar to the difference/improvement made by my previous upgrade to FM springs and Tokico Illuminas (plus new urethane bump stops from another vendor).

No downsides (except I'm glad I didn't lay on my back for hours under jackstands to install them); highly recommended.
Review by Pat / (Posted on 8/7/2015)
Frame Rail Reinforcements are a winner.
Finally got around to installing the frame rails last month and I love them. IMHO the reports of improved ride quality over bumpy roads are not exaggerated. My ’94 did not have any squeaks or creaks that I noticed (old guy here that tends to crank up volume of the classic rock FM station, FM cat and catback installed) so I can’t comment on any body noise improvement.

If you massage damaged stock rails with a hammer you might get showered with beach sand. Previous owner had driven my Miata on the ocean beach. I bought my Miata over 5 years ago and was amazed on the amount of fine beach sand that I had to flush out of the driver side stock rail. Beach sand was no longer salty but I imagine the sand was at least a bit abrasive as it shifted a bit while driving. Might be wise to flush out the stock rails and maybe squirt some sort of undercoating in them.

I was going to mount a vise on my floor jack to straighten the damage on stock rails but tried a cheap Harbor Freight C clamp with a short piece of wood first. Stock rail metal is soft so the C clamps easily did the trick.

If you are hesitating over buying the rail reinforcements I suggest you just go ahead and do it.

I keep wavering about ordering the butterfly brace upgrade, actually ordered and canceled before I installed the frame rails. Now I am back to thinking I will add the butterfly brace in the future.

I would buy the FM rail reinforcements again.
Review by dmcfz30 / (Posted on 7/13/2015)
Frame brace
Installed these on each of my Miata's ('90 stocker and '05 MSM). Have hardtops on both with usual hardtop squeaky noises on bumps. Frame rails noticeably reduced these noises as a result of much less body/frame flexing. Significant gains on rough roads. Totally happy with these. Special thanks to Brandon for his "shop tour" and technical help during my recent visit.
Review by mtn-miata / (Posted on 6/8/2015)
At first I was hesitant, but these really make a difference.
I am no longer afraid of potholes! These really stiffened up the chassis and it rides much better in corners and rough pavement and bumps. I no longer cringe over potholes or entering driveways at an angle. Body feels much tighter and responsive. No more creaks in the dash. I have vmaxx classics and FM sway bars and noticed more body roll after the frame braces I assume because the chassis isn't twisting as much and the suspension is doing more of the work. I love these things the bonus features is the stainless construction and they can be used as jacking points. Very straightforward install.
Review by VonMoldy / (Posted on 5/16/2015)
The least expensive and most effective handling upgrade
Frame rail stiffening immediately changed the attitude of the car. It tightened up a floppy 20 year old chassis better than almost any other mod for me. The install was straightforward and the fit was perfect. The only problems you may run into is if you have deformed frame rails from speedbumps but they are easy enough to manipulate back into shape with a hammer or other large tools. We paired these with a set of sway bars and now we can't take a corner without grinning.
Review by Werdna / (Posted on 3/20/2015)
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Why stop here? Consider this upgrade.