Originally Posted by W Cole
I have searched thoroughly and am very surprised that I couldn't find anyone who has lowered their non-ZCP car by installing ZCP springs. I saw one member who retrofitted the entire ZCP strut and spring assembly onto this non-ZCP car and I noted in one post he questioned if the ZCP struts are any different than non-ZCP.
There seems to be a ton of conflicting information about the differences between ZCP and non-ZCP cars. I was wondering if anyone could lend some insight on the following:
- Are the ZCP struts different than non-ZCP?
- How is the lowering accomplished on a ZCP car? Springs? Different spring pads? Altered spring perch location? Or a combination of?
I could be going in the wrong direction entirely and perhaps this is why no one else has attempted this. I am looking for a very mild drop that will not prematurely wear out my struts and other suspension components. Perhaps the Dinan stage 1 kit is my best bet as I have read it provides a very similar ride height to ZCP?
I'm the guy who did the ZCP conversion.
I don't think there's clear consensus on what the difference between the struts are, primarily because there are no obvious visual differences between the two. My belief is that their valving and compression rates are a bit different based solely on the fact that they have different part numbers and different prices. It was also interesting to note that the ZCP struts are the same ones found on the 1M and the standard Japanese market M3.
As for the lowering, there's also no consensus there. The only difference in part numbers between ZCP and non-ZCP cars are the struts and springs -- the spring pads are the same part. It's either done through the springs or the spring perches (though as some have noted, the difference in perch location is practically imperceptible between the two struts).
Why not just order ZCP springs and see if you get the drop. As I recall, they're cheaper than the Dinan Stage I kit. If you don't get the drop, then you can either return the springs or buy the struts. Either way, you'd confirm where the drop comes from.