So right now I am having this problem with this rattle from under the left valve cover. I have been driving the car like the technician told me to do and it seems as if the car is losing power. I pulled into a cruise night parking lot and this guy approached told me it sounded like I have a bent pushrod and I could have ruined the camshaft by driving it. I started to notice that the car doesn't pull like it was so this guys opinion makes some sense to me. I'm no mechanic and I don't know what this guys expertise is either at this point it could be anything. I'm taking the car in tomorrow to have them figure out the issue. If my camshaft is ruined, bad lifter, or bad rocker, what would be good replacements for these items? Since my car is a B4C 5.0 5 speed it already has the bigger cam in it. Is there a bigger cam I can run? I have been reading the LT1 cam is better than what I have and I also have been reading about a Crane cam. At this point I am doing my due diligence and I don't know exactly what the issue is. Since I need to get this issue fixed I'd like to get some extra power in the process. Any help is appreciated.

 

Chances are it's just something on the top end - loose rocker, etc.

If it's a flat cam lobe...... scrap the 305 and get a 350. There will be metal debris from the flat cam all through the engine and generally that requires a full tear down and rebuild to clean it all out.... which isn't worth doing on a 305. The fix there is a 350 crate motor, etc.

Again - I doubt this is the case. But if the rockers have gone to **** then that also indicates excessive wear and the cause should be investigated. It may be an indication that the engine is starting to wear out and if that's the case you'll be money ahead just getting a crate.

GD

 

The loss of power is likely due to false knock and the resulting spark retard from the noisy valve train.

At a minimum pull the valve cover and find what is loose. Then go from there.

RBob.

 

Get the valve cover off first and do some investigating. Hopefully just a loose rocker, maybe broke valve spring. Assuming your car has the original engine (91) you would have a roller tappet camshaft which typically do not have lifter related failures on engines that have been maintained.