Premium shock absorbers on standard springs - too stiff?

[twr7cx]

I've been reading/researching in regards to my upcoming suspension refresher (89 NA6 with standard suspension, torn strut boots and collapsed upper mounts) yet I've been unable to find an answer to this specific question as all the threads/reviews I've found discuss the shock absorbers with aftermarket springs which are lower and harder. I'm looking to retain the standard swaybars and coil springs as I haven't been unhappy with it's performance and would prefer to retain the more comfortable ride over lowered harder springs. As part of this I would look to change to Fat Cat Motorsport / 5X Racing Street Bump Stops Micro-Cell Urethane 46mm to assist in improving suspension travel and comfort.

When selecting shock absorbers, would a premium shock absorber (such as Bilstein HD, Koni Sport, Koni SRT or KYB AGX) be a mismatch (poor choice) due to their firmer valving with the soft standard springs?

Would I be better off using the cheaper KYB Excel-G or Sachs Premium shock absorbers to match the stock spring rates?

[Code4]

At 190,000 km on my NB8A I replaced all four shocks with Kong STR'S keeping the standard springs (which last forever). Also used the fat cat bump stops. The thin rubbers on the top of the springs probably could have been replaced but I didn't and have had no issues. For a comfortable street/touring ride this set up has been without fault. Obstacle clearance concerns stopped me using lower aftermarket springs though the konis can handle a small drop in height. The only other change that improved comfort and reduced NVH was an Automotive Plus roll bar. Hope this helps. Bought everything through MOSS in the USA but not sure if they still export.

[twr7cx]

That helps a lot, thanks. My preference is to purchase a premium shock absorber rather than just an OEM equivalent, but I didn’t want to spend the extra if it would be a mismatch for factory springs. Normally I prefer Bilstein on previous vehicles but I’ve read negative things about their valving on the NA so was leaning towards the Koni SRT as I don’t hav the patience to play with the adjustability that the Sports provide.

[hks_kansei]

Stiffer shocks on standard springs will work fine.

Obviously within reason, super stiff race style shocks work be great, but what you've listed are all fine for normal springs. (Most lowering springs aren't that much stiffer than factory anyway)

With regard to bump stops, just make sure that whichever ones you use still actually stop the shock before it bottoms out.
No point having extra travel if the first big bump punches the end of the shock rod to bits.

[twr7cx]

With regard to bump stops, just make sure that whichever ones you use still actually stop the shock before it bottoms out.
No point having extra travel if the first big bump punches the end of the shock rod to bits.

Thanks for the tip and I fully agree with what you have said. Thankfully 5X Racing seem to have made that incredibly easy to achieve as when order the Street Bump Stop Kits for 1990-1997 Mazda Miata from their website < http://5xracing.com/i-20915224-5x-racin ... op%2Bmiata > you select the shock absorber you are using with it and it supplies the appropriate size bump stop, washer and any spacers required (e.g. Koni seem to require spacers). It seems their kits are based on or an evolution of the old Fat Cat Motorsports products that are often favourably talked about on the miata.net Forum.

[StanTheMan]

sorry wrong answer

[Mr Morlock]

driving a car for many of us is simply a balance between good handling- normally a given with the MX5 a sports car- and comfort. The quickest way to alienate many drivers from using the car too much is a hard ride.You can drive sports cars at more than twice the cost of an MX-5 i.e. new price that don't ride as well as an MX-5 crazy but true. An MX that has done heaps of KLM will do very nice with new shockers or maybe they are still acceptable. . All the advertising is just telling you what wonder products they have and some times you have to wonder. Drive the car first and see how it travels before making changes .

[wasp47]

Think about buying your KONIs from the UK, you don't have to pay the UK VAT 20%,which cancels the freight cost. Still a lot cheaper than buying here. Food for thought.
Cheers
Steven

[Wivvix]

When selecting shock absorbers, would a premium shock absorber (such as Bilstein HD, Koni Sport, Koni SRT or KYB AGX) be a mismatch (poor choice) due to their firmer valving with the soft standard springs?

Bilstein B4's might last just as long as Bilstein HD's, depending on the application. The B4's may also ride a lot better than the HD's, depending on the spring type and spring rates used. My mate tried HD's on his NA6 with OEM and king springs - the ride was jarring either way.

Would I be better off using the cheaper KYB Excel-G or Sachs Premium shock absorbers to match the stock spring rates?

Since you want to keep the stock ride characteristics, I would look at Bilstein B4's or KYB GR-2/Excel-G's. These were designed (valved) as replacements to suit the OE springs. The other shocks mentioned above (HD's, Sport's, SRT's and AGX's) were designed primarily to suit higher spring rate applications.

If you are concerned about quality, find out where they are made and choose one that's made in Germany or Japan.