Who has thrown a rocker arm before, and am I suffering valve float?

[josh817]

I over did it today and threw a rocker. One of those gut wrenching moments when I heart a pop and then a tap tap tap tap. Thinking to myself I'm not in the position to have something break on me right now.

 

I was happy to see that it was just a rocker that came off. It nicked the cam lobe right on the edge, so it doesn't affect the wipe pad. The thing I wasn't happy to see was that the pivot had unscrewed itself all the way down. After checking all the other valves for clearance I started her up, she runs much more smooth. Before, if you were holding the throttle at a certain point above 3000RPM when the cam is coming in, it would start choking and stuff. Plus, every time you went to shift and let off the throttle you would get a big backfire, when typically I only get backfires if I let the engine brake me. Symptoms are gone now. Made sure everything was tight. My question is are these "mouse trap" springs enough to hold rockers in at higher RPM's? They don't appear to be very competent, just by looking at them and seeing that you can easy take one off with your hands.

 

Also:

I baby my motor, its never seen past 5500RPM. Its not only that though... For some reason if I floor it, it will come up to about 5500 or 6000RPM, you feel it accelerating, and then its like it hit a rev limiter. Sounds like a rev limiter, and it feels like one. You almost fall forward, because the power just stops. However, if I do 75% throttle, it can ease its way up to about 6500-7000RPM, thats as much as I can take before worrying, and it is precisely when I threw a rocker. I am running a Schneider "stage iv" cam which is 295º/.490", along with their springs. Intake is triple Weber 40's, and I am running an HEI module with a '77 dizzy I think it is. I don't think its valve float, but who knows, maybe. I want to say it could be carbs since I have NEVER touched them. They bolted on and ran. Don't mess with it if it works. I was thinking maybe the motor is choking since I did some porting, which is at most like a "mild" job by professional standards probably. However, I'm thinking maybe it IS valve float because at 100% throttle, it occurs, like the rapid RPM acceleration is the culprit compared to slowly creeping higher like I did today. I think ignition is the last of my worries. I only list it because I remember reading on here that the HEI modules drop off in performance when you hit the 5000-6000RPM mark?

 

Anyway yah, it was just one of those moments where I was like oh no what have I done. The last mile to the shop I was thinking what it could be because it was ticking pretty bad but not at the speed of a piston. I thought maybe I kissed a valve or something is getting ground up inside the cylinder, worst case scenario, but it wasn't like a thrashing from hell sort of noise, just a loud tick and a lack of any power. Glad it worked out for the best, easy fix, took ten minutes and $0.

Edited May 6, 2010 by josh817