As I mentioned, I just put a Spec Stg. 2 + (
456 lb/ft capacity) with the lightweight steel single-mass flywheel in my car yesterday.
Only issue during install was the center bore of the flywheel was a little small and needed to be honed a tad, but it's on and performing flawlessly thus far. Everyone complains about chattering with the single-mass flywheel, but I barely hear anything but a faint rattle at idle.
The entire rotating assembly (steel flywheel, pressure plate, and clutch) weighs in at
11 lbs. less than the stock assembly. 40 lbs. total for the stock parts and 29 for the Spec parts.
As it turns out, however, my stock clutch actually hasn't failed at all. The friction surface of the disc is just a bit glazed and smoothed out which led to the slipping I was experiencing. Scuffing it up a bit should bring it back to normal operation again. Unfortunately in my case, this just can't be determined until it's removed and a replacement purchased under the assumption of what appears to have been a complete failure.
I realize that some people appear to have tons of issues with Spec, but I know from working in the industry that problems posted on the internet, while seemingly abundant, really only represent a small percentage of actual problems. Additionally, many of the issues I've seen in my research seem to be with clutchs very similar in torque capacity to their OEM counterparts when something of a higher capacity should have been used. Additionally, many complaints are more often simply hearsay perpetuated by friends of friends who have no firsthand experience, which exacerbates the apparent severity of the failures.
I am in no way affiliated with nor defending Spec; I have no reason to. I have never used their products in the past, nor was I given any discount or sponsorship on this setup. I'm just willing to give them the benefit of the doubt and trust that it will operate as advertised.
I will obviously keep the potential issues in mind, however, and report any problems should they arise, but everything is working fine so far, and I'm confident that won't change. Time will tell.
Here are some photos of the Spec:
As well as the glazed but reusable stock clutch: