- My model of MX-5 is: Sport Tech NC3
- I’m based near: Milton Keynes
- I’m looking for technical help or recommendations on: Bilstein rear shocks
I’ve recently become the owner of a 2014 Sport Tech.
It needs new rear shocks and I want to replace like-for-like.
The Mazda part number I’ve been given is NH47-28-700A.
This translates to 24-131759 in Bilstein which appears to be the only B6 option for all NCs.
However MX5 Parts lists 2 different Bilstein rear shocks, one soft-top, one hard-top.
Does anybody know the full story? Is the shock available from Bilstein for £150 the same as the Bilstein shock from MX5 Parts for £238?!
Ask Bilstein supplier whether it comes with the spring or whether only sells the damper. The spring stiffness in the suspension has changed a number of times mostly to lower the static sag height of the car.
If I were you I would ask an mx5 suspension specialist that will know the right answer.
I believe the spring on the PHRT maybe slightly stiffer and thats maybe why there probably are two part numbers. However I have a feeling that the’re “maybe” slightly different top hats on the PHRT rear shock as well - but not 100% sure on that
A person you may want to ask is paul roddinson @https://www.mx5-racing.co.uk/ - he will tell you all you need to know mate
A very good question to ask!
I have the 3.75 Sport Tech too and have also previously researched those…
I do know that the rear body wing configuration is different between the two because of the weight of the hard top etc etc.
Mine not needed yet, but like to have the information to hand.
If Mazda are quoting you £150 per unit I would be inclined to go there.
Curiously, what do MX5 Parts say on the subject?
Are they really different somehow in width/length/build?
Please keep us posted. 
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I have a 3.5 Sport Tech PRHT, and recently fitted a set of Bilstein B6 shocks (part numbers 24-131759 & 24-131742), but I reused the existing springs. If this is what you’re planning on doing, then you should be fine. Hope this helps!
I bought new Bilstein B6s from Demon Tweeks and fitted them with the existing springs. Great improvement - currently listed at £155 front/£165 rear.
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I have front and back shocks that I replaced on my 2014 sport-tech that you I can sell you. I had the shorter springs added last year but found the car was a tad too low so got new BC racing adjustable coilovers put on instead.
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Thanks to everyone for their input.
I got this info from Mark at MX5parts (hope he doesn’t mind me quoting him):
“The Mazda-supplied Bilstein shocks are not the same as the aftermarket Bilstein shocks sold by Bilstein stockists.
The Mazda shocks are specially made to Mazda’s specification by Bilstein and supplied to Mazda. The damping rate is tailored to the Spring rate used by Mazda in that application.
The aftermarket non-Mazda Bilstein shocks are generic shocks made to work with the standard springs.”
While I’m sure the B6 shocks would be fine, definitely better than the rear shocks I have which have been misting for the last 4 years (before I owned the car) the purist in me wants the original fitment. So I guess my credit card will be sustaining fairly serious damage at MX5parts quite soon…
Thanks for that.
Curiously, what is the difference in price from a Mazda dealer?
Cheapest Bilstein B6 I found was £144.94.
The Mazda equivalent from MX5Parts is £237.94.
I don’t know what a Mazda dealer would charge now but the previous owner was quoted £450 each 4 years ago but that did include fitting.
Any advance on an hour a corner?