FatCat Motorsports Shock Mount Review (10mm kit).

The alignment has been checked, the street testing phase is done, and the verdict is in.

First and foremost, here is a little information about the test vehicle: It’s a daily driven 1991 Miata. 137,800 miles on the chassis and the bushings. KYB AGX shock absorbers (a little over 90,000 miles on them) with stock 91 springs and FCM 54mm bumpstops, shocks were set to 3 all around before and after the shock mount installation. 7/8ths Flyin’Miata front swaybar set to its stiffest setting, with RacingBeat adjustable end-links.

Handling Impressions: The best way to describe the handling improvement(s) with the new mounts would be to tell you that it feels like a slightly softer sprung NB rather than an NA, only with a slightly more flimsy chassis. But some of you may not have driven an NB, so I’ll elaborate a bit more… Turn-in response has been greatly improved, with the steering feeling more direct than before, almost as if you had added stiffer springs front and rear (in fact, it actually reminds me a great deal of my RB spring setup, but without the jittery ride and more severe initial impact over bumps that the stiffer springs exhibited.)

I also noted a definite improvement in lateral traction, though how much is tough to quantify without an instrumented test. Should you decide to test out this improved lateral traction for yourself and overstep the limits of adhesion, you’ll be happy to know that the car has also become more predictable at the limit, and breaks traction in a more gradual and more controlled manner, making it even easier then before to reign back in.

The Ride: NVH has definitely been reduced. If I had to put a number on such things, I would say a 15 to 20% reduction in NVH has been made with these MCU equipped mounts over the NA pieces. The first thing that strikes you is how much more supple the car feels going over a bump. It has a more solid “thump” rather then the normal “thunkity-bumpity-whoosh-bang-fizz!” that comes from daring to use your NA on anything but the smoothest of streets. Much of the peripheral bumps that usually come back to you through the steering and seat have been filtered out very nicely, no more of that “if you run over an ant you can tell how many legs the ant had” ride quality.

On the highway, body movements after driving over a dip or over surface undulations on the highway are better kept in check then before, and with this new found sense of damping comes a somewhat dulled sensation of speed (for example, I’ve found 80 mph feels more like 70 did with the NA mounts, 70 more like 60, 60 more like, well you get the idea…) In fact, the whole car actually feels like it’s being sucked down against the pavement, but at a ride height of 12.1 inches front and rear, that shouldn’t be surprising.

There is something I’ve never seen mentioned in any review for the FCM mounts, so it led me to think this observation was just a placebo effect, but when two passengers on two separate occasions noted the same thing, I knew it wasn’t just my mind playing tricks on me (I’m too young for that anyway...) The road-noise coming up from the tires seems to have been reduced to a point where the predominant noise in the cabin is the gentle hum of the engine rather than the howl of the Azenis at highway speeds. How this is being accomplished I have no idea, just an observation (and some clarification would be more than welcomed.)

Downsides: There are only two minor downsides to performing the upgrade to the FCM mounts that I can think of… The first problem is the ride height when used with 90-93 OEM springs. I can definitely see some people not wanting the lower ride height that comes with these mounts, and 12.1 inches is fairly low for a daily driver (not for me however, and YMMV of course.) The second issue is really just more of a minor annoyance, and that’s the increased bump-steer that comes with lowering the car, but you could upgrade to either 93LE or 94R tie-rod ends to help alleviate this problem (but honestly, you can concern yourself with much bigger issues in the handling and ride equation then chasing down bump-steer issues. )

Having said all that, I firmly believe that the benefits in handling and ride quality that come from performing this upgrade are well worth the minor annoyances I’ve mentioned above.

In Conclusion: I’ve performed plenty of “modifications” on my suspension setup over the years, but this is honestly one of the only modifications I’ve made, that truly qualifies as a fully-fledged upgrade, and not just another “modification.”

There you have it. The MCU equipped FCM mounts get the Goji seal of approval. I’m just sorry I didn’t upgrade sooner and spare myself allot of wasted time and money with my lowering spring excursions back in 05 and 06 (check the suspension page on this site for more information about that...)

Jeff "Goji" Anderson-Lester