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Hi guys,

Tomorrow i'm installing new shocks on my NA.
I'm just wondering where the top hat should sit along the threaded shaft; right at the base or higher up?
There's no guidance provided in the manufacturer's instructions.

In case someone asks, the labels read from top to bottom, thick nut (blue), thin nut (red), spacer (green), top mount (black).

Cheers

When you pull your old shocks out take note of where all the parts go
And it is BIG nutt first the thin nut is the lock nut
See here for NB shock
http://www.fatcatmotorsports.com/FCM_shock_mount_install.pdf

Right at the base. Snug it down before locking the nuts in place, or else the shock post will flop around.

I'm slightly surprised that there is no rubber/polyurethane damper in there...?

Russellb wrote:When you pull your old shocks out take note of where all the parts go
And it is BIG nutt first the thin nut is the lock nut
See here for NB shock
http://www.fatcatmotorsports.com/FCM_shock_mount_install.pdf

Originally I thought so too, but then I saw this.

http://www.boltscience.com/pages/twonuts.htm

zossy1 wrote:Right at the base. Snug it down before locking the nuts in place, or else the shock post will flop around.

I'm slightly surprised that there is no rubber/polyurethane damper in there...?

Do you mean the MCU bumpstop? You can sort of see the top of one on the left shock body.
Or do you mean a rubber isolator between the spring and top mount?

Wivvix wrote:

Russellb wrote:And it is BIG nutt first the thin nut is the lock nut

Originally I thought so too, but then I saw this.

http://www.boltscience.com/pages/twonuts.htm

Well I'll Be I've always gone big nut little nut.
I will be doing it the other way from now

Wivvix wrote:Do you mean the MCU bumpstop? You can sort of see the top of one on the left shock body.
Or do you mean a rubber isolator between the spring and top mount?

Not the bumpstop - that is to stop the top of the reservoir from crashing into the top hat at max compression.

What I am talking about is a system to provide some cushioning to the top hat mount itself. I have seen pillowball top hats and they generally operate without rubber (albeit with a large and tightly tensioned ball joint), but with a flat top mount like yours appears to be, I would have thought that a system similar to the OEM Mazda setup would be preferable. IIRC, Mazda use a hard rubber damper on the top hat, half of which lives under the top hat and half of which lives on top (with the top hat sandwiched in between). This stops the top hat from vibrating and smashing itself to pieces as the shock does its work. There is a massive amount of force applied to the top hat at the point of connection with the shock slider and it is wise from an engineering standpoint to spread this load over a wider area and damp it as much as possible.

My V-Maxx coilovers (which admittedly use OEM NB top hats) use this system also.

EDIT: OK, just re-read your original post and I now get the impression that these are just replacement shocks - not some new setup? In this case, reuse your OEM mounts as has been said and take note of the order the rubbers come off. You will see the rubbers I am talking about when you pull the old ones off. Don't leave them out whatever you do!

zossy1 wrote:

Wivvix wrote:Do you mean the MCU bumpstop? You can sort of see the top of one on the left shock body.
Or do you mean a rubber isolator between the spring and top mount?

Not the bumpstop - that is to stop the top of the reservoir from crashing into the top hat at max compression.

What I am talking about is a system to provide some cushioning to the top hat mount itself. I have seen pillowball top hats and they generally operate without rubber (albeit with a large and tightly tensioned ball joint), but with a flat top mount like yours appears to be, I would have thought that a system similar to the OEM Mazda setup would be preferable. IIRC, Mazda use a hard rubber damper on the top hat, half of which lives under the top hat and half of which lives on top (with the top hat sandwiched in between). This stops the top hat from vibrating and smashing itself to pieces as the shock does its work. There is a massive amount of force applied to the top hat at the point of connection with the shock slider and it is wise from an engineering standpoint to spread this load over a wider area and damp it as much as possible.

My V-Maxx coilovers (which admittedly use OEM NB top hats) use this system also.

Ah. I probably should have clarified. The "top mount" depicted in that image is for representational purposes only. I will be using standard NA (rubber) top hats.

Wivvix wrote:Ah. I probably should have clarified. The "top mount" depicted in that image is only for representational purposes only. I will be using standard NA (rubber) top hats.

Yep, I need to RTFQ more carefully ;)