Evo Flywheel Converter Kit.

[Nick Mann Services]

This topic is coming up more and more at the moment, so please let me share with you what I have learned and what I am selling!

The VR4 clutch is very similar to the Evo clutch. The pressure plate on the evo has a slightly different shape to the springs, making it slightly deeper in size to the VR4, but the flywheel/crank fitting is substantially different, leading to a much shallower flywheel on the Evo. The bolt spacing on the flywheel is the same, and the bolts connecting the pressure plate to the flywheel are identical. The release bearing is identical. The Evo clutches and especially flywheels are cheaper and easier to source when compared with the VR4 stuff.

So in my opinion, the options for a VR4 clutch are:

1. Stick with stuff designed to fit. You know it has been designed for the car, so get peace of mind. The significant draw back to this is that uprated stuff is difficult to get and expensive.

2. Stick with the VR4 flywheel and use an Evo pressure plate/friction plate (That's what most traders sell as a clutch kit.) There are two things to think about here. Firstly, most clutch suppliers will not offer any guarantee on friction plates unless they are coupled with a new flywheel. Secondly, the Evo preesure plate is deeper than the VR4 one, leading to the release bearing sitting in a slightly different place. I have been told by someone who should know that this often leads to higher friction plate wear and early death for the clutch. I have no first hand proof of this myself.

3. Change the whole assembly for an Evo setup. This needs an adapter for the flywheel to crank join. I have taken measurements of the starter ring teeth and the overall assembly sizes and have then asked a local machine shop to manufacture these rings for me. So the Evo flywheel can now be bolted to the VR4 crank. This should solve any premature wear problems - the assembly should now be sat in the right place. It also means that Evo clutches can be used, which as stated above, tend to be easier to get and cheaper to buy for performance items. The one negative of all this is that the flywheel bolts normally used for the VR4 are now around 5-6 mm further out of their threads than normal. They have a 1mm thread pitch, so that is 6 turns! There is a longer bolt available, though, with an extra 7mm on it. Perfect!

So I am selling one aluminium spacer for £35 with the chance of buying 7 bolts with it for a further £25. Postage to the UK is £5. The picture below shows the kit, two bolts out of the bag so you can see them and one original VR4 bolt.

There are several kits in use now and so far I only have good feedback!