427 valve lash

[arrowdriver]

In my going over the car I bought I pulled all the plugs and valve covers to check a few things. The plugs look ok but some are a bit whiter than I think they should be, considering colder plugs and perhaps richening the carb a bit. The valve lash on a couple of intakes that I measured were about 0.038, which seems way too much. From my experience this should be more like 0.020, 0.025 at most. The heads are iron.

I would be interested in what others running these engines suggest.

[Jim Harding]

.038 seems too wide for me too. But unless you know who made the cam and what grind it is, you're lost as to what is the correct gap to set them at. On my car, the cam card states .020 (hot).
I recall from days gone by, that you could fudge both the intake and exhaust lash settings to squeeze out that last fraction of HP. These were not more than few thousandths. Going more or less than .007 to .008 either way was pushing it (as I remember), so having the right lash adjustment is necessary to prevent damage. Too loose increases the noise and increases the wear on the valve train components. Too tight increases the likely hood of burnt valves.

[Naumoff]

.020 hot is good.
And is safe if you don't have a cam card.

[arrowdriver]

Thanks, I think I will for now at least use 0.028 cold which seems to be the Ford spec. Not hard to reset this if I get better info on the cam

I'm also changing to a colder plug so will see what difference this makes. Might also be a good time to check the resistance of the wires.