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Reason being, the flywheel and clutch of my SE have concentric circles machined into the flywheel and replicated into the clutch face. Most bizzare. I have never seen it before and just wondered if that's something that exedy do with their clutch kits. The clutch looks like it's got kevlar running through it but the flywheel doesn't have any stampings on it to say it's an exedy.

Anyway, just in case an NB or NA 1.8 owner for that matter wants a clutch upgrade, the SE clutch kit is a seperate part number than a standard NB8B clutch kit. Furthermore, the flywheels are the same for all NBs including the SE. The concentric circles machined into the clutch contact surface are factory from Mazda and the guys I've shown it to today suggest its very smart engineering.

I'm intrigued. Have you got a photo of the flywheel and clutch plate?

Not yet, but I will take one and post when I get a chance. The clutch plate is just an exedy organic with kevlar fibres - same as on their website. The clutch cover looks stock but being matched to the exedy clutch I'm guessing it ain't.

So obviously it's more surface area so it's beter at heat disappation. But, more importantly, it was described to me that at high revs, the air pressure inside the bellhousing actually makes the clutch stick to the flywheel. The pattern allows air to be trapped between the plate and the flywheel and as such it releases better at high revs. Sounds plausible to me. All three guys I took it to are very skilled and experienced engine builders.

So, it begs the question and I did ask them, that for most aftermarket clutches, they require a freshly ground flywheel. For this one, they all said not to bother and it should be fine. I think I'll keep the exedy one that was in it handy....just in case.