In the process of rebuilding this b16a head when I noticed 5 of the 8 Ferrea exhaust valves had this weird lip running all the way around the face of the valve?.... not to sure what to make of it. Any ideas?

 

Pretty sure I solved it.... I think this is what happens when your piston to valve clearance is just tiny little itsy bitsy too tight!
Like it only touches at near redline.
Everything stretches... including connecting rods.





The last few times I ran this engine I felt like something just wasn't right so I was pretty gentle on her. That explains the dent but the thin layer of carbon build up.





ahhh closure.

 

I disagree with your hypothesis. Aluminum is not going to be hard enough to peen steel like that.

I think you are looking at valve to valve clearance issues. What do the intake valves look like?

 

Thats what I was originally thinking but its the only explanation. No marks whatsoever on the intake valves they look new. There are only dings on the exhaust side of the pistons too. 5 of the 8 valves have the lip and there are only dings in 5 of the 8 valve reliefs on the Piston face.

That aluminum piston is far softer than the valve but maybe the carbon getting caught between is abrasive enough?

 

After millions and millions of impacts...... maybe. At least this is my best guess so far.

Mirror finish should do her well.

 

Piston to valve contact usually marks the piston not the valve. I have a little experience with that. One instance was run for a long time with the piston closing the exhaust valves. Not a mark on the valves only the piston.

If it were carbon abrasives the valve material would just be gone. Yours appears to have more of a peened over look. The material is still there just not where it should be.

The direction of that material flow is not consistent with the the piston pushing the valve upward. Looks more like the edge of the valve being dragged over something as it is closing. Like an intake valve that has opened. As the exhaust is closing the intake is opening. With big overlap the intake might already be open.

What engine and what cams? What cam timing if adjustable?

 

What does the edge of the intake valve look like? And the seat?

 

I'll get some more details once I get back home.

 

You son of a gun! Called it.
I can't believe I missed that.

 

Nifty!

 

So my next question is do I advance the exhaust cam a hair or retard the intake?

Besides the fact that I got valves touching it seems to run so good. I would think I wouldn't need a retune....

 

Can't say for sure without measuring your piston to valve clearance on the VTEC lobes for both cams at a various points in the rotation.

I would put it back together exactly as it was and measure piston to valve every 2 degrees near the valve opening and closing events. Then decided how much room you have to advance and retard timings.

Be sure to measure piston to valve again after making changes.

 

If your valves are touching each other, you need to decrease the valve overlap. Either advance the exhaust or retard the intake. Being the Intake valve events have a much greater effect on power than the exhaust, I would advance the exhaust.
You should go ahead and degree the cams and check ALL your valve clearances at different settings while its all apart.

 

Someone suggested to just cut like .010" off the valves and leave the tune alone. I don't really see anything wrong with it. If anything its less area for the charge to go around...=Mo Powaaaaa! Lol

any thoughts?

 

You would still have to check clearance and you would lose the nitride coating. Plus the labor.

If it is really that close just retard the intake a degree or two. Still would need to check clearance. Doubt that small change would have a huge impact on the tune.

You can shortcut all you want but the results may not be what you are after.