bought a set, on the intake side of intake valve there is oil after running motor (SBC) 20hrs and heads are on the bench look down the runner and theres oil on top of all 8 intake valves, put new guide seals from dart 32$ and six passes down 300ft track still oil, WHAT GIVES????? never had this much trouble with wore out stock parts! any help i can get would be geat THANKS!                               THE DUCK

if the heads have been milled at all the intake needs to be cut to match .

you might be sucking the oil down the stem when you shut down at high RPM.  Here's how I cam up with that.
Running down the track you are at high Revs when you shut down, and the following stuff is all going on.
1) The valve covers are full of oil after a 12 second long hard high Rev run.
2) The crank case is under pressure from blow-by and heat expansion.
3) The valves are "wiggling" with each stroke at those high Revs.  Even good ones wiggle if they are pushed by a rocker.
4) When the throttle is cut at high RPM there is a vaccuum created in the intake area.  This means each intake valve's stem is under the effects of a bit of vaccuum when it gets opened.  The piston is headed down and the valve is headed down and the vaccuum is looking for air.

So, maybe the oil is setting on the stems when you shut down at high Revs and gets pulled down the stems from the high vaccuum created at that point of shut-down.  Might go away if you put a positive crank ventilator that gets tugged from the exhaust.  That would create a vaccuum in the valve cover/crank case area that would continue even after shut down because the exhaust is still moving a volume of air that should overcome any high rev vaccuum in the intake.

If it was a seal or guide issue there would be smoke and oil use.

Anyways, I thought I'd toss out an idea.  Good luck

had the same problem and had to have a complete valve job, its sad that they send new heads out this way

guess im screwed