Lowering SE springs

Aiming Faster · Postby **Aiming Faster** » Thu Oct 08, 2015 1:34 am

Hi, I installed some (low mileage?) SE shocks onto my NB8A, which caused it to lift around 10mm. Suggests the originals were saggy.
Any issue with trimming off 30mm from the SE springs? As it is now, there's around 70mm between tyre and guard.
I saw that someone installed adjustable sleeves, which would be preferred, but I see that job getting big enough to stall me.
Bring out the thoughts! Thanks, D.

Postby **beavis** » Thu Oct 08, 2015 1:53 am

I did exactly that on my NA.
Installed SE shocks with 'reduced height' springs.
Ride is firm but good for the street, spring is still sitting firmly in the shock.
There is a nicer and more even gap between the wheel/tyre and the guard.

RS2000 · Postby **RS2000** » Fri Oct 09, 2015 8:21 am

You probably know this Aiming Faster, but just incase you don't :

The car won't lower by the amount you cut off the spring free length, as the spring rate goes up. The spring rate will increase roughly the same % as the % you reduce the number of coils by. Obviously the ride will be a bit stiffer too.

Cheers

Aiming Faster · Postby **Aiming Faster** » Fri Oct 23, 2015 12:16 am

Thanks for that, the other option is to machine the inside of the lower spring 'perch' where the captive circlip sits, anyone know how much I can lower the perch by safely?
I was hoping for 25 or 30mm, but hard to know where the clip is without removing from the car/disassembling.
Thanks, D.

Aiming Faster · Postby **Aiming Faster** » Mon Oct 26, 2015 9:43 pm

Next option would be to machine a replica groove into the shock body, 30mm lower.
Keeps the spring original-but-lower, can be reversed later down the track, if requirements change.
I will extend the top mounts by 25mm to retain the damper rod travel, whichever method I go with.
Unlike you guys to be shy with the suggestions!!!
Thanks, D.

hks_kansei · Postby **hks_kansei** » Mon Oct 26, 2015 9:49 pm

RS2000 wrote:You probably know this Aiming Faster, but just incase you don't :

The car won't lower by the amount you cut off the spring free length, as the spring rate goes up. The spring rate will increase roughly the same % as the % you reduce the number of coils by. Obviously the ride will be a bit stiffer too.

Cheers

Depends on the spring, linear rate will drop by a similar amount to the amount cut off, progressive will depend which end you cut.

in saying that, MX5 springs are stupidly long, so you can probably cut off a good 2 inches before it's not captive..

hks_kansei · Postby **hks_kansei** » Mon Oct 26, 2015 9:53 pm

Aiming Faster wrote:Next option would be to machine a replica groove into the shock body, 30mm lower.
Keeps the spring original-but-lower, can be reversed later down the track, if requirements change.
I will extend the top mounts by 25mm to retain the damper rod travel, whichever method I go with.
Unlike you guys to be shy with the suggestions!!!
Thanks, D.

Personally i'd just get lowered springs before having the perches machined.
Most lowering springs are between 25 and 40mm lower, so perfect ofr what you want.

Probably cheaper than getting a shop to machine the shocks too.