Hi, this is my first post of what will probably be many.... Let me first start out by saying that this is my first BBC and I absolutely love it. Im currently running it in my jetboat.Im running a 1979 mark iv 454 with 049 heads. Im not sure what if anything has been done to the engine other than I know that its a Hardin Marine engine... It came with a dual point Mallory dizzy and Holley 850 double pumper. Holley mech fuel pump and Hardin Marine log/snails exhaust.
After the first season of owning the boat/engine which ran pretty good, I wanted to do some upgrades. During the winter I ditched the Dual points and added a Pertronix unit. I went ahead and ditched the old looking Accel wires and install a set of Pertronix wires too. When it came to spark plugs I took my set out which were Autolites (which im not a fan of) and hit the parts store. I found out there that the previous owner install the wrong plugs which were the bigger plugs. I ended up going with the smaller NGK yr5s gapped to 35. The engine really liked the new additions. Start ups were quick and it ran smooth from idle to about 4200 which was my max rpm. After those mods I found a good deal on an intake and installed an Edelbrock HIGH RISE dual plane intake to replace the very low rise stock iron anchor intake. I couldnt believe how heavy that thing was! Bolted up the Holley and the rat like it even more. The engine had more overall pep than before. (Im not sure about how much hp was gained but Id like to say it was noticeable). The last modification was a to the jet pump that got the boat out of the water some which let my motor spin a little higher on the top end from 4200 to about 4700rpm.
Ok, so thats where I am at now.
I ran this set up going on year two with no problems.
I should note that when I first bought the boat I did a compression test and all cylinders were close to the same, with only the #8 cylinder being about 7.lbs lower. That spark plug was a little heavy on the oil too.
On the subject of oil I run 10-30 synthetic blend along with some Lucas oil that a buddy gave me to try. He claimed it made his jet run better so I gave it a try. My engine always made some valvetrain noise so just for kicks I added the Lucas stuff while the engine was warmed up and running. I noticed right off the bat that the engine quieted down and seemed to run smoother. I definitely heard some ticking go away about 30 seconds after adding the stuff.
Anyways not trying to be an infomercial here....
So this year I did no mods.... Everything running as usual except the valvetrain noise has been getting louder lately. From about idle to 3k everyting sounds fine.... then from about 3500 on up it chatters. Chatter goes away when I let of the gas.
I did some research and found out that I could adjust the lash on this BBC so I went ahead and did that. While I was in there I checked for correct torque on head and rockers. I have a hydraulic flat tappet cam with stock stamped steel rockers. Single valve springs with dampeners.
This is what I noticed while in there... When I removed the rockers I could spin the valve springs. I mean that I could spin the springs with my fingers. Exhaust and Intake springs.
Is this normal?