Ticking in the valve train

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Sweetjones

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I have just got my 340 together and have been trying to adjust the valves so I can start the break in process. I've only let the motor run for 30seconds to a minute each time I start it because I'm scared I'm going to chew the new cam up. I'll do my best to exsplain what I have. Stock rotating assembly but bored thirty over. When I bought the motor it had already been rebuilt. I replaced the x heads with edelbrock rpm aluminum heads and used the same aluminum roller rockers and shafts an push rods. It had a tick to it before when the other heads (x heads) where installed. There are also some spots where the top of the valve springs are just barely hitting the spring pocket on the rocker arms. Also the rocker arms have no numbers or identifying marks on them neither do the push rods. The cam is a lunadi voodoo with a .513 lift (can't remember duration off hand). When i adjust the rockers to have a quarter turn of preload the motor is so tight it won't start. Also the adjustment screws on the roller rockers are a pretty good ways out from the locking nut. Can someone point me in the direction to the correct rocker arms and push rods. This set up I'm using now is just not working and I'm getting very frustrated. Ha ha. Any help will be greatly appreciated.
 
Sorry to say it, but by running and then shutting off the car without breaking in the cam for 20 minutes at various speeds above 2500rpm, you are almost guaranteeing a flat cam lobe. All your cam break-in lube is gone after the first few cranks, so it's up to your oil to keep things lubed while the lifters and the lobes mate together in their spinning pattern. The first 20 minutes or so are critical to cam and liter life.

Your valve train doesn't match your heads, your rocker arms are hitting the valve springs. If your new heads have pushrod guide plates and you are running non-hardened pushrods, you will have more problems.

Did you check for spring and rocker interference prior to starting the motor, and consider addressing that? Did you check any of your valve train related geometry and/or opt for some correct length pushrods?
 
I just used what I had. I've already thrown a ton of money into this project. I've been reading here on the forums that the shafts have a orientation that they need to be in so I'm sure that's one of the problems. I'm going to replace the rocker arms with a set I found that are made for that particular cylinder head and hope that gets it done. As far as push rods I am assumeing there stock. Hope I haven't ruined anything already!
 
Did you check valve to piston clearance? I built a 340 that was similar. I used the pistons that were in it and heads that were on it. I put a new cam in it and had issues with valves hitting the top of the pistons.
 
No I haven't checked that nor do I even know how to. Lol turns out I did have the rocker shafts on upside down but I'm putting back some paychecks so I can order some new rocker arms and pushrods. Thanks for the advice!
 
If the springs are hitting the rockers as you say, there's your noise. I also agree that if you keep cutting the engine off before you've broken in the cam and lifters, you are askin for trouble. Get those rockers off, locate the witness marks and clearance all of them accordingly with a die grinder and reassemble.

Lastly, those Voodoo cams are very aggressive lobe designs. Couple those with roller rockers and you will likely have a somewhat noisy valve train. It's simply the nature of the beast.
 
It has been quite the hassle but I will post an update so other people can learn from my mistakes! First off I took the roller rockers off and had the spring pocket milled down about an 1/8 inch. That solved that problem. The next issue was my push rods where too long. I ordered a set that you cut and press yourself and NO machineshop in my area would touch them!!! So I took them to my uncle (who's a machinist) he cut and pressed the first cup on and split the other end of the pushrod! So that was about $130 down the drain. After that I printed off a order form for smith brothers and sent it in. Got the new ones in about a week and they are perfect and smith brothers service was great!! Now I have everything back together and went threw the break in process an re adjusted the valves and she sounds beautiful! Thanks everybody for the input hope you can learn from my mistakes!!
 
You figured out the basics, & fixed it. A 2-400 bones is cheap,compared to what some people spend. You did ,well.
 
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