I am bringing a question from another model (e46 m3, S54 4-valve shhhh!) to this forum.
This project started with an increasing valve tick that has proven to be 2 worn rockers. There isn't
a learned discussion of what to keep and what to replace, most are replacing all 24 rockers and both camshafts.
The theory is that rockers and camshafts wear in together, but more importantly, offers an opportunity to
hop things up.
These camshafts were inspected closely by 2 machinists who determined that they can be returned to service.
I was considering swapping in just 8 but decided to splurge on 24 so that in case the noise comes back,
it won't be rockers, it will definitely be camshafts. Them Shrick DLC "diamond-like-coating" rockers are blingy.
There are some discussions of valve train, crankshaft, and diff work that refer to some of the processes
above. I probed some posters about the how and why, and the explanation that comes forward
amounts to upselling.
On the topic of micropolishing a serviceable, scratch-free camshaft: I am reminded of a medical
report on most modes of knee cartilage damage that concludes no difference in long term function
or pain with or without surgery. But I overthink...
This is probably a DonL question: can anybody report experience/recommendations with small-shop surface prep techniques? Maybe I need to go find the SBC hotrod guys.
This project started with an increasing valve tick that has proven to be 2 worn rockers. There isn't
a learned discussion of what to keep and what to replace, most are replacing all 24 rockers and both camshafts.
The theory is that rockers and camshafts wear in together, but more importantly, offers an opportunity to
hop things up.
These camshafts were inspected closely by 2 machinists who determined that they can be returned to service.
I was considering swapping in just 8 but decided to splurge on 24 so that in case the noise comes back,
it won't be rockers, it will definitely be camshafts. Them Shrick DLC "diamond-like-coating" rockers are blingy.
There are some discussions of valve train, crankshaft, and diff work that refer to some of the processes
above. I probed some posters about the how and why, and the explanation that comes forward
amounts to upselling.
On the topic of micropolishing a serviceable, scratch-free camshaft: I am reminded of a medical
report on most modes of knee cartilage damage that concludes no difference in long term function
or pain with or without surgery. But I overthink...
This is probably a DonL question: can anybody report experience/recommendations with small-shop surface prep techniques? Maybe I need to go find the SBC hotrod guys.
