Valves on new rebuild, When to re-adjust Options

[jeffdon]

Been driving with the new engine, and probably have all of an hour and a half behind the wheel. The engine has quite the clattering noise that I notice at idle, which I assume is the valves. I set (and re-set) them three times before it went in the car. My webcam 494 spec card showed to set both valves to .006. I went with .007, based on the common thinking that its better to be a little loose. I am running stock push rods.

Just climbed under the car thinking to check the valves, and am really not looking forward to this. I have set them with the engine in the car in the past, and cannot recall it being such a crappy job.

I guess my question boils down to this:

Should I put more road time on the car before adjusting the valves? Or am I better off letting things break in more before doing the adjust. I am thinking if the valves are making noise, they may be loose, which is way better than too tight, allthough the performance would be down.

Whats all ya'lls consensus?

[Jake Raby]

The web recommendations do not consider the pushrods material you'll be using. Do some searches. We run chromoly pushrods and web cams with zero lash cold. Look at the 160k mile teardown of my 912e engine I built in 2002. It went over 120k of that with zero Valve adjustments. That cam has a 494 intake lobe.

Lash is determined by expansion, expansion is heavily impacted by material.