1990 Corvette 113 heads refreshed less than 200 miles ago, 1991 Vette block bored .30, Mahle hyper pistons, Lt4 valve springs and keepers, Lt4 hotcam, Crane gold non-SA roller rockers (part# 19002-16), 7.2 hardened pushrods, isky adjustable guide plates, hedman elite headers with Percy's deadsoft gaskets.

I've been messing with this thing for nearly 6 months trying to get rid of what sounds to me like a valvetrain noise. It started after I had the heads refreshed which included new seats, install of springs, valves checked and ground and pressure test. While I was trying to figure out this noise it started blowing oil out of the valve covers so I had the "new" short block built. I reused the heads since I had the $$ into them already. Guy that built the block also installed heads, set preload, etc.

Installed the "new" engine thinking that I would never hear that annoying noise again. NOT! I know that the rollers are going to make some noise but I don't think it's supposed to be this loud.

http://youtu.be/mVYujR0lgO0





I looked at the valve stems and it looks like the rockers are contacting in the right place there so I don't think it is a geometry issue. I guess it could be a header leak.

I don't know, I'm stuck and tired of throwing $$ at this damned car.

Any suggestions?

Thanks,
Jeff

 

Are you 100% sure the lifter preload is adjusted correctly?

 

I adjusted the preload by watching the intake valve on one cylinder, after it had opened I continued turning until it was atleast 2/3 closed then I adjusted the exhaust. Then I rotated engine until the exhaust was just starting to open and I did the intake.

 

Roller rockers are louder. If its to loud 4 ya put your stockers back on and see if you like it better.

 

Did you ever find the cure to your noise?

 

I have.

I had to use ISKY adjustable pushrod guides and adjust the rockers with the engine running. Yes, they are still louder than stock. That wasn't my real concern.