Collets and Valve Spring Caps

[northernboy]

I am just re assembling my 1098 12G202 head and notice the collets and caps don't look just right.

Looking back at photos before I stripped it is the same as i found it.

It just looks like the collets are protruding a little too high above the caps and their appears to be gaps between the collets.

Am I correct in thinking these are designed to have the spring clips added, thus the additional height, but people tent to leave these clips out?

[philthehill]

I would suggest that the collets are sitting correctly in the top cap as I have checked your photo against a fully assembled head I have on the shelf.
It is normal for there to be gaps between the collets. The gap ensures that the collet is sitting fully home in the spring top cap.
The early 'A' Series had the spring clips fitted but it was found that there was no requirement for them so were deleted by the factory. This led to the adoption of the shorter collet which appears visually to sit deeper in the spring top cap but to all intents and purposes fits exactly the same in the top cap.
The original thinking behind the fitment of the collet spring clips was that at high rpm the collet may decide to pop out with disastrous consequences so the collet spring clip was fitted.
So long as the collet and spring top cap are matched then there will be no problem as regards the collet popping out.
As your engine has been running as is then it appears that the collets and the spring top cap are matched.
Just assemble and enjoy.
At the same time as the collet spring was deleted the valve guide shroud and flat seal which fitted under the spring top cap were deleted because again they served no purpose as regards keeping oil from the valve guide.
The best you can do is fit the valve guides with groove and attached to them the top hat seals. Both guide and top hat seals are available from ESM and other suppliers.

[northernboy]

Thanks Phil - advice always appreciated.