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Rectifying non-captive springs in Zeal coilovers

Hello all,

So, I've taken my new R33 GT-R through its rego inspection (in the ACT you have to go through the government pits. It's worth just going and seeing what they find as if you return with everything rectified within a month you only pay an additional $16 or so). Mostly all stuff I anticipated that's easy enough to fix, like the exhaust being too loud. The one surprise has been that the springs in the coilovers aren't captive under full droop, such as when the car is jacked up. For background the car is on Zeal coilovers (sub brand of Endless), unsure if they're function x or something else as I haven't had a chance to properly get under the car myself. I've taken it to my suspension guy (Ian at Revell in Fyshwick), who's said if I don't want to lower the car further the fix is helper/tender springs (people don't seem to be able to agree which name goes with which thing - here we mean the super low rate springs that coil bind as soon as the car sits on the suspension and only extend to pin the springs in place under droop) which will cost almost a grand after parts and labour.

Before I drop that kind of money I want to be sure it's the way to go, so I've been doing my research. So firstly I'd like to check I've understood the problem properly. As I understand it the issue goes like this. With coilovers unless they have independent height adjustment ride height changes are made by winding the seat of the spring up and down, adjusting the preload and how much it's squished by. Non-captive springs happen when the seat isn't wound up enough, allowing the spring to fully extend under droop and rattle around. Is that correct? What I don't understand is why a kit that I assume was designed for this model of car would have such a problem within its range of adjustment. Is it just operating at a ride height higher than the manufacturer intended?

Secondly, I obviously need to work out the best way to fix this. Again as I understand it the possible solutions worth exploring are:

  1. Lower the car more. It's not crazy low but clearance at the front is marginal already in a lot of environments including the ramp to my apartment complex parking. The current front splitter is already scraped underneath but I don't want to break anything, and ultimately I'm planning to put a carbon fibre item on and would like to avoid destroying it.
  2. Helper/tender springs. A decent chunk of money but will properly fix the problem, retain the current ride height and not mess with the properties of the suspension under driving conditions. Can also potentially be reused on other coilovers I might fit in the future.
  3. Replace springs with longer springs.
  4. Replace coilovers with different coilovers that don't have this issue at the desired height or with a separate spring and damper combo.

Whilst I'm thinking I might eventually replace the coilovers with Ohlins ones down the track, I had planned for that to be in several years after doing a bunch of other work on the car, as it seems the current Zeal coilovers are reasonably well regarded. Is that the case? I'm leaning towards just getting the helper/tender springs, but want to make sure I'm not just throwing good money after a bad setup. I'm planning to keep this car until they put me in a box, so want to do it right.

 

TLDR - Zeal coilover springs aren't captive under droop, should I fix with tender springs or are these coilovers junk and I should replace with a new system instead of spending money fixing them?

I could be wrong, and someone with more knowledge than I will surely come along and help, however, using the below pic of generic Zeal Coilovers as an example, the height adjustment is separate to the spring seat adjustment, so you should be able to adjust the Lower Spring Seat & Lock ring (2 rings below the spring) to fully captivate the spring at droop, (what effects this has on the ride comfort with pre-loading I don't know). 

The ring at the very bottom is the one used to adjust the ride height, so if this is what your coilovers look like, you should be fine without having to adjust the height.

$1000 to install helper springs is ridiculous, pretty sure you can  buy them for about $50, but I guess there is a lot of labour in removing, pulling apart, reinstalling and aligning. but you shouldn't need to do this.

Hopefully.

Jonathans-Zeal-Coilovers-005.jpg

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You need a helper spring.  They are not expensive.  Find out what the inside diameter of you springs are (Would guess 65mm), what height you need to bridge and go from there.

http://eibach.com/de/en/motorsport/products/eibach-helper-system

Edited by djr81

While I agree, they are kind of expensive if you take into account that you may need intermediate spring seats (between the main and helper spring) as well as the springs. and the labour assuming its not DIY

You could just lower the car so they are captive to get through the pits.....

I wouldn't swap out working zeals for new bilsteins, they are a reasonable shock and its not really an upgrade unless they needed a rebuild anyway.

My 32 had zeal coilovers on it when I first got it and mine were junk. They were the stiffest things I have ever felt and despite trying some much lighter springs to try and get some (if not ANY) travel they made little difference and were only fit for the bin. Bought a set of near new Australian made Shockworks coilovers which made an absolute world of difference!!

Okay, so I finally had a chance to get under the car over the weekend properly. GTofuS-T gets a cookie, they do indeed look like they're independently height adjustable, and besides that the springs spin but don't rattle so even if they're at full height already the lowering would be in the order of a couple of mm to fix it. They'd been slipping up more and more lately for me and a few friends, but I think I'll be going somewhere else for suspension stuff from now on!

Not that it matters, but for background the quote was something like $88 bucks a spring, $33 bucks a spacer and the rest was labour for fitting them and a full alignment. But that's money I don't have to spend now! Just need to work out what size range c spanners to get and I can do it myself.

 

 

  • Like 1

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