Originally Posted by Doug Stirling
A certain tuner on here (he builds proper big power engines) is quite happy to avoid verniers
If asked by the customer, he will time up the cams by REMOVING the keys.........therefore setting up the timing (on engine dyno) and then tightening up the nut to the new settings.........as long as the nut is properly tightened it is safe.
I'd sooner have the insurance of the key as well TBH, but its perfectly possible like that, thats how Zetecs work anyway IIRC, and lots of other engines for that matter, obviously they are designed that way from the outset though not just done as an afterthought.
All down to personal preference, but as you say the nut (well bolt actually, not that it matters!) tightened properly should hold it in place well enough, especially if its a race engine and hence only run for a few hours between rebuilds anyway.