valve guide sizes
 

How do I work out which valve guide size/oversize to fit to my SC heads. Have just removed the original guides, and am about to fit new valves too - the stem wear is apparent, while the faces are very good. The internal guide size will obviously be standard with new valves, but how do I calculate if I need oversize OD, or do you just go up a size after pressing old ones out?
Thanks
Alan

Hello, Alan.

I stopped doing this myself.

The specialist head shops do it much quicker and cheaper and do it right..

The process involves removing the old guides veery carefully to avoid broaching the hole, then measure the hole, then size the oversize guide in the lathe.

All the details are in the manuals and spec books..

The heads need heating very hot, and thr gudes in the deepfreexe..

Good luck..if you get it wrong the head will crack or the guide drop..

Kind regards
David

Hi David,
Many thanks for advice. Whether I fit the new ones, am undecided as yet. But need to order the parts (via Pelican), and trying to decide what I should be ordering in terms of guides. Am doing complete strip down, so trying to compile list of components.
Regards
Alan