Need help:
I have a shelby csx 4000 cobra with a shelby 427 aluminum block with edelbrock aluminum heads,comp cam roller rocker on solid lifters.
On two occasions the rockers have broken apart (as if peeled back and split from the bottom belly). The car has a tendancy to knock when I shut it off. I am running pump gas (premium 94 octain), the comp is 11 to 1.
The first break occured pulling into my driveway at almost no speed, the other time I think it may occurred when shutting off the engine. I have heard that the spring tension may be too high or is it possible the rocker is just not strong enough, possibly not enough oiling. I don't like the fact that the raw aluminum rocker is riding on a metal shaft (these rockers have no bushing or needle bearings).
My engine builder wants to make the car hydrolic roller being a street car. He insisted we make the car a solid lifter car a few years ago. Changing to hydrolic does not explain or cure the reason for rocker failure. Can someone please help. This is become a real pain and at times I want to just get rid of the car. More time being repaired than driving.
I have a shelby csx 4000 cobra with a shelby 427 aluminum block with edelbrock aluminum heads,comp cam roller rocker on solid lifters.
On two occasions the rockers have broken apart (as if peeled back and split from the bottom belly). The car has a tendancy to knock when I shut it off. I am running pump gas (premium 94 octain), the comp is 11 to 1.
The first break occured pulling into my driveway at almost no speed, the other time I think it may occurred when shutting off the engine. I have heard that the spring tension may be too high or is it possible the rocker is just not strong enough, possibly not enough oiling. I don't like the fact that the raw aluminum rocker is riding on a metal shaft (these rockers have no bushing or needle bearings).
My engine builder wants to make the car hydrolic roller being a street car. He insisted we make the car a solid lifter car a few years ago. Changing to hydrolic does not explain or cure the reason for rocker failure. Can someone please help. This is become a real pain and at times I want to just get rid of the car. More time being repaired than driving.