k, just pulled my motor for my ls/vtec build. got the head off and looked at the valves and the intake valves were black and the exhaust valves were white. thought it was weird since on all the heads ive ever pulled they were black. I have my timing advaced to 18btdc and im running 90 octane. so whats the deal folks?

 

anyone? i know white usually means its running lean/hot but wouldnt it be on both intake and exhaust valves? its just got me wondering what the hell is going on with my engine.

 

so no one on here has experienced this? comon i came to this forum b/c i had been told i could find 99.9% of my questions. cant find any valves posts other than upgrading them. if no one knows then could someone please refer me to a better site?

 

wow ive never seen that. appears to be running a little lean

 

the engine is stock and im running with no catback. both o2 sensors are in and functioning. no check engine light. i was getting a boost of power over stock with the timing advanved 18deg. butt dyno was saying an additional 5-7hp. no pinging either. how would half be white and black?

 

team-integra.net
theintegra forums.com(<-- no spaces though)

 

thanks

 

like to know also. my exhaust was brown an my intake was black, what would that be a sign on? all stock with 60 k

 

I had the same question https://honda-tech.com/zerothread?id=1839488 and I got different answers from different people. I bought an engine that only had this in one combustion chamber, the one with bent valves.

 

You can try the All-Motor forum, might get more help. I can tell you that the intake valves will usually be darker than the exhaust valves, that is normal. On the exhaust stroke, the hot gases after combustion are exiting over the faces of those valves as apposed to intake valves that only see cooler fuel/air gases entering past them on the backside of the valve.

It does appear that you are running lean. So you have a stock engine, a stock exhaust manifold, cat conv. and air intake but you disconnected the exhaust to run on the dyno or track? Is that what you mean by no cat-back? I could see running advanced timing and no exhaust leading to a lean condition.

Could have been a valve lash problem or even a skipped tooth on the timing belt causing the exhaust valves to open or close slightly off the perfect timing. I admit to not knowing what a burnt valve looks like, but your pics seem to point in that direction.

 

^^^^^EXACTLY WHAT I WAS LOOKING FOR! That made so much sense and I now know my mistake. I believe I skipped a tooth. I junked the stock exhaust because it had holes thru out it. Glad I caught it this soon. I would say they arent burnt yet but were on there way to total annihilation! Thanks again everyone that posted.

 

update to an old post. those images are showing highway mileage! long duration trips made the exhaust valves red hot and they turned white. head was running perfect.