Miata Shock Question

91 Miata, with old AGX shocks and FM springs (shorter and stiffer).

I went with this setup because the stock springs and shock had be slamming into every speed bump in town, no matter how slowly I went over them. The FM springs are shorter, but stiffer. No more slamming into the tops of speed bumps.

Several hundred thousand miles later, those AGX shocks are worn out. Even set on 8 they leave the car riding like a buckboard. It doesn't pogo-stick, but it sure jars and slams the wheels up to the stops over bumps.

The question is, what shocks to replace these with, without breaking the bank, and getting adequate damping for the stiffer springs.

I'm also figuring I probably should replace the bump stops, which may or may not even be there any longer. I was thinking of getting the longer "comfort" ride types. My thinking is that even with the car lowered, so I'm more likely to be bouncing on them, I'd be doing so more linearly and therefore with less jar.

Any thoughts? Especially from you Keith?

Or, maybe I should just sell it and buy a Buick for the daily commuting slog.

Stock Bilsteins, maybe some extended top hats for the rear, and some FCM-ish bumpstops.

Definitely not stock NA Bilsteins. Tokico Illuminas are the best bet. They'll work better than those AGXs ever did - less harshness. We've got a 54mm urethane bumpstop that works very nicely. The extended upper mounts (an FM exclusive!) make a big difference by adding more than an inch of compression travel in the rear, but they're not the least expensive option.

Yes, harshness and joggle are things I still need to avoid. The beloved Harley has been really teaching me this. The Miata has been giving me follow up lessons.

Kieth, the only bump stop I see listed on the FM web page is just identified as being "improved". No dimensions are listed. Is this the same as the 54mm bump stop you mentioned?

At $519, those Tokiko's are not cheap. We're also close to the price of Koni Sport shocks (in fact, Goodwin has them on sale for $3 less). Any thoughts on the Tokiko vs Koni Sports?

It's stupid, I know, but I see weird named shocks on ebay for $120-140 for set of 4. The cheapness appeals to me, though I suspect their lifespan is measured in weeks. Oddly, I've found a few reviews of some over on the Miata board by folk who claim to have tried them, said they weren't all that bad after all.

Yes, that's the one. Definitely improved over the hard stock ones.

We offer the Koni Sport as well, and we're also offering the Koni sale price. Given my choice, though, I'd put on the Tokicos. In fact, I'm going to pull a set of Konis off my own street Miata shortly to reinstall the Tokicos.

I cannot comment on "weird named shocks" without knowing more. Keep in mind that your stiffer springs require a shock with more damping, so you cannot use a stock replacement. No Koni STR.T, no KYB GR2, no Showa. The Illuminas might be more expensive, but you'll only have to buy them once. We're talking about an extra $400 every couple of hundred thousand miles!

Swank Force One wrote: Stock Bilsteins, maybe some extended top hats for the rear, and some FCM-ish bumpstops.

You do mean NB billies and NB mounts right? Because no one should ever put NA shocks and NA mounts back in a miata once they've been removed.

Leafy wrote:

Swank Force One wrote: Stock Bilsteins, maybe some extended top hats for the rear, and some FCM-ish bumpstops.

You do mean NB billies and NB mounts right? Because no one should ever put NA shocks and NA mounts back in a miata once they've been removed.

Well, yeah.

Keith Tanner wrote: Yes, that's the one. Definitely improved over the hard stock ones. We offer the Koni Sport as well, and we're also offering the Koni sale price. Given my choice, though, I'd put on the Tokicos. In fact, I'm going to pull a set of Konis off my own street Miata shortly to reinstall the Tokicos. I cannot comment on "weird named shocks" without knowing more. Keep in mind that your stiffer springs require a shock with more damping, so you cannot use a stock replacement. No Koni STR.T, no KYB GR2, no Showa. The Illuminas might be more expensive, but you'll only have to buy them once. We're talking about an extra $400 every couple of hundred thousand miles!

Cool, send me the Koni's then. I'll appreciate it!

M3Loco wrote:

Keith Tanner wrote: Yes, that's the one. Definitely improved over the hard stock ones. We offer the Koni Sport as well, and we're also offering the Koni sale price. Given my choice, though, I'd put on the Tokicos. In fact, I'm going to pull a set of Konis off my own street Miata shortly to reinstall the Tokicos. I cannot comment on "weird named shocks" without knowing more. Keep in mind that your stiffer springs require a shock with more damping, so you cannot use a stock replacement. No Koni STR.T, no KYB GR2, no Showa. The Illuminas might be more expensive, but you'll only have to buy them once. We're talking about an extra $400 every couple of hundred thousand miles!

Cool, send me the Koni's then. I'll appreciate it!

You say that now, until the konis pound your spine into your spleen.

Leafy wrote:

M3Loco wrote:

Keith Tanner wrote: Yes, that's the one. Definitely improved over the hard stock ones. We offer the Koni Sport as well, and we're also offering the Koni sale price. Given my choice, though, I'd put on the Tokicos. In fact, I'm going to pull a set of Konis off my own street Miata shortly to reinstall the Tokicos. I cannot comment on "weird named shocks" without knowing more. Keep in mind that your stiffer springs require a shock with more damping, so you cannot use a stock replacement. No Koni STR.T, no KYB GR2, no Showa. The Illuminas might be more expensive, but you'll only have to buy them once. We're talking about an extra $400 every couple of hundred thousand miles!

Cool, send me the Koni's then. I'll appreciate it!

You say that now, until the konis pound your spine into your spleen.

Damn, that bad? I'll have to make that VA appointment sooner then..

Of the shocks capable of handling those springs the only thing to ride worse than the konis would be R package or NA Billie HD shocks. Although if you turned the konis up too far they would ride worse than the r-package. R-package shock ride is bad because WAY TO MUCH rebound, koni ride is bad because not enough low speed compression and too much high speed.

Leafy wrote:

Swank Force One wrote: Stock Bilsteins, maybe some extended top hats for the rear, and some FCM-ish bumpstops.

You do mean NB billies and NB mounts right? Because no one should ever put NA shocks and NA mounts back in a miata once they've been removed.

No. The NA stuff isn't that bad, and there's lots of incorrect info out there as to travel. The NB mounts don't give more travel. They add more rubber between the shock shaft and the mount, which interestingly is viewed as a bad thing in the high end coilover market but viewed as a good thing in the consumer end.

If you're going to go with NB parts, you need to change the springs, shocks and upper mounts. You can bodge together bits and pieces, but you end up losing compression travel and messing with the designed ride height.

Keith Tanner wrote:

Leafy wrote:

Swank Force One wrote: Stock Bilsteins, maybe some extended top hats for the rear, and some FCM-ish bumpstops.

You do mean NB billies and NB mounts right? Because no one should ever put NA shocks and NA mounts back in a miata once they've been removed.

No. The NA stuff isn't that bad, and there's lots of incorrect info out there as to travel. The NB mounts don't give more travel. If you're going to go with NB parts, you need to change the springs, shocks and upper mounts. You can bodge together bits and pieces, but you end up losing compression travel and messing with the designed ride height.

Its not that the NB mounts are all that much better, its that all the shock options for NA mounts suck.

We're going to have to disagree on that one.

Break the bank, and get a set of Xidas!

How easy is it to skip the spring compressor and just leave the top hat in the car and lower the shock out with the lower control arm on a jack? On say the Spitfire and a few others, it's simple enough, and saves a good bit of time. Not so sure about the Miata. Looks doable enough, especially with the FM springs, since I rather suspect they're shorter. Any of you guys do it this way?

Doing a little google research, I see I should pull the trunk carpet and look at the condition of the rear hats. See if the shocks are actually just bouncing up and down because the rubber has given way. Haven't bothered with doing that yet, just assumed the clunking and thuds in the rear were the differential bouncing around on it's thoroughly worn out bushings.