Emillio are the above comments with NB top hats or AST top mounts?

Suspension theory question-if you have a 7 inch spring with some preload on the rear isn't that enough to extend the shock on dips and broken pavement? And isn't the unsprung weight enough to continue to extend the shock once the spring is totally extended?

a 7" spring is long enough where you'd start to run into problems with spring bind...

As long as it`s still loose at full droop you might run into a situation where the shock does not extend enough into the dip. Unsprung weight will not be enough to push the tire down. Not fast enough and will not take any load when extended and therefore not really doing anything...

I have Xidas and 7" springs in the rear. No problem with bind. See video;

http://vimeo.com/37469352

^ Great video :)

Wow. I should have kept my mouth shut. I could have sworn when i did all my beer can measuring it wouldn't work out. Failure.

indeed. that's a great vid. thanks for posting it.

related: is the motion ratio of the miata ~1.6?

I think Brain and others have had issues with softer 6 inch springs.

6" springs made my piggly MSM sit way to low in the rear for street duty. And I don`t even have a rollbar yet...

Fronts are fine with 6" springs, even have some compression left on the helpers with car static on the ground.

7" in the rear gives me my desired ride height, but need extra bushing on shaft to have enough droop available to let the helper do more than beeing a spring spacer. Also full droop is most likely way out of range of of the chassis ability to move independently with the rear swaybar connected.

I will make new video with the new spring locators and 6" springs along with FM`s tophat spacers to see if it will put the suspension in the correct range of motion. Maybe what the MSM`s should really have is a heavier rate helper...