zeroptzero

since it's a JDM engine, any chance detonation could cause the damage ?

fernando.

lol @ people saying it's because he was at or near red-line for too long - the motor is designed to rev safely to 9000rpm's, hitting the limiter once, twice or 50 times SHOULD NOT cause this.

Part of me wants to think it's because you had a tight valve, once you hit the limiter it cuts fuel and essentially leans out the motor for a split second and it get pretty damn hot when that happens.

Either that, or oil pressure and/or lubrication somehow was lost on the rocker arm pivot causing it to seize/become over heated and give way.

Slowcrash_101

Maybe you stripped a jam nut and the adjustment screw tightened itself until catastrophe.

Also, OP said the cam journals and cams looked great, so it's not an oil starvation issue, and I doubt it's an overheating issue.

I agree with you though, I think a tight valve caused this.

windhund116

Seems like floated valve. Piston hit and fatally damaged the valve.

windhund116

JOC... any update? Hope rest of engine wasn't damaged too badly.

VTEC4-2

An overrev could happen on a 3>4 shift if the clutch was pushed in before removing the foot off the accelerator, and the increased revs happened more quickly than the limiter could respond to.

Or the gear selected was actually second.

I believe that rocker arm was a secondary victim after the valve and piston unfortunately met.

From the pictures, it appears that the damage was on the primary lobe - which could indicate VTEC was not engaged at the time the rocker arm cracked. Is there any additional pictures of the rocker arm or VTEC actuation pin which would reveal this?

Billman250

I strongly agree the broken rocker arm did not happen first. I think a massive blow to the rocker by the piston, using the valve as a punch.

The adjuster and locknut appear to be in proper height, so it seems adjustment was not an issue.

Quite the mystery.

RickyLee

thumbs up
its a mystery

OP keep us update please