Long story short at the track last year (second to last pass) i started hearing a very audible intermittent clicking coming from my head. we decided to run it anyways. we made another pass and it lost a cylinder. i pulled the valve cover when i got home and one of the rockers split and pooped all the needle bearings into the pan. I replaced the intake valves on the dead cylinder and that was the end of it.

ok so fast forward, i just got my car started a few days ago. drove it a bit and shut it down cause of a few misc oil leaks. I pulled the valve cover to fix a leak and what did I see? THE SAME ROCKER(replaced of course) SPLIT OPEN. same position as last year.

I had ALL 16 valves replaced previously for the season, only thing that remained the same was the guides. I also put a kiggly HLA in. I did spin bearings twice last season due to other problems. could a chunk of bearing lodged its way in an oil passage to the lifter and is causing my problem? I'd like to be able to have the car hold together this season...

What causes these to break? Should i change out heads? any idea what would be breaking them like this? its odd how its split the same as last year(maybe i magically used the broken lifter some how and put it on the same valve? lol)

 

Pics would help alot.

 

Have you ever bleed the lifters?

 

are you running ignition based cuts? i.e. anti lag, launch control, flat throttle shifting?
what valve springs, seats and retainers are you running?

 

I have heard ofthis before as well.

how many revs you spinning it to?

any idea of your VS installed heights & seat pressures?

just curious, which cylinder?

how does the cam lobe wipe across the roller? is the lobe centered above the roller or could the lobe slighly side loaded?

who made the cams & what spec/version?

 

Of course I've bled my lifters lol but I am running ferrea singles with supertech guides and seals. I am not sure of seating pressures or heights. Also the cams are gsc s3s(also brand new for this season). The cams are fairly new so wipe is hard to really see but everything looks centred. The part that strikes me odd is this roller broke the exact same way how the last one did. It splits open about 3 cm. I have plenty of spare rockers but I don't know how happy I'll be when one of those needle bearings makes its way into the pick up...

 

sounds like your s3 cams might be too much for your valvetrain, those are some aggressive cams, sounds to me like check your valve guide height, make your seals for valve stems are intact, well one thing you can do is since you have to many rocker arms breaking, see if you can send em out to be cryo treated as an option, cryo treating goes down to the molecular level to strengthen the parts...could be worth it to look into that.

 

op, what cylinder??? #3 or 4?

did you have the kiggly oil pressure thingy installed for during both of your rocker failures?

 

3, it was the 5th intake valve from the timing belt. and i've had this failure with BC 280s and no kiggly HLA and then again with GSC S3s and a Kiggly HLA

 

When you had the head off were there marks on the piston? I'm thinking valve float.

 

Last time I pulled the head when it first broke the rocker it bent the valve there was contact. But what is weird this time is the car drove 22 miles and never went above 4k so it wouldn't of had the opportunity to float

 

This is from what I've read - I'm no race engine mechanic - when valves float the springs develop harmonics (they are vibrating a lot) and this quickly heats them up and the springs can lose all strength. I'd suggest pulling the offending springs and having them checked out.

 

So afree pulling the pan, I found No needle bearings. This leads me to belive that I some how put the bad rocker back in...

 

Wait....you pulled the back rocker, then put it back in?! You didn't pull it and toss it? Oh jeez!

 

I guess... I got nothing.