dropped valve : (
Well its offiical I killed it I admit it, I was doing the burnout and the motor started to miss when I hit high gear pulled up to the staging lights and gassed it once to see if it would clear up and it was smoking something terrible so I cut it off, got help pushing it back and on the trailer and finished watching the races contemplating what had happened to motor.
After removing the valve covers noticed #1 and #3 cylinders rockers were loose as hell, removed intake and head on that side and well it was a mess to say the least. It had dropped the intake valve on #1 cylinder, the valve banged around on the piston for a while till got small enough to be sucked into the intake and then into the next cylinder where it got lodged in the intake port of # 3 and bent the intake valve there. several peices of the valve and or piston made there way around in the intake wrecking havoc on 2 more pistons before it all was said and done. 2 pistons damaged and one completly gone, #1 cylinder's combustion chamber looks like hell but I think it can be fixed, the cylinder wall is screwed too so a sleeve will need to be put in there.
My question here is how long should a set of valves be run before you would replace them to prevent this from happening again? Or do they even need to be replace periodioticly?
As far as I know these valves have been in this motor for more than 4 plus years and I was thinking that was along time. The springs were replaced last year along with new keepers.
I had been driving this car almost 2 seasons now for a friend and we've never had any problems till tis happened, I asked the owner he has had any previous valve train related problems before I drove it and he said never.
The motor is a bbc 468 13 to 1, 722 lunati solid roller cam, grumpy jenkins merlin heads w/ stud guirdle. Motor has never been sprayed w/ nos and I shifted it out at 6800 via an electric shifter so its never over reved.
Im building a 496 for my car and I'd like a heads up on if and when to replace "things" to prevent this from happening to me, or anybody else for that matter. Any info would be greatly appreciated.