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If anybody can help me with this I would greatlty appreciate it. I was building up the my 5.0 in my 95 ford mustang. I put a B303 cam, gt40 intake, full length headers, and I had some work done on my cylinder heads. They milled .003 off my heads and put bigger intake/exhaust valves, and port/polished them. After I put everything together I started the motor and the lifters/pushrods were making a very loud noise. I took the valve covers back off and noticed the pushrods on all the exhaust valves were bent. I called the guy that did the work on the heads and he said the valve springs were only made to handle .460 lift and the cam lift is .480. Obviously, I have a problem here - but my question is why did it not bend the pushrods for any of the intake valves? The cam is balanced .480/.480 intake/exhaust. It appears the intake/exhaust springs are the same. Any help would be greatly appreciated. (the guys suggested buying springs that would handle upto .500 valve lift) Would that really solve my problem or does another one exist.
 

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Did you shim the rocker arms when you put it all back together? You may not need to but w/ the different cam & head milling your rocker arm geometry and pushrod length might be off.
 

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what valves did you use.
were they stock length and did they cut them in so the valve stem height was same as stock? With non adjustable valvetrain if ANYTHING changes you can have all kinds of diff probs
 

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Exhaust valve hit pistons w/ bigger cam? Just thought, not a good one though
 

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Does the B cam use the stock valve springs? If so it shouldn't have coil bound the valve springs unless you have something else wrong like too long push rods or the valve spring installed heighths were wrong.
 

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Discussion Starter #6
I am using the stock pushrods. Since the heads were milled .003 I used shims the same width under the roller rockers. I will have to check into the valve lengths.
 

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samhane:
were your heads milled .003 or .030? I didnt think you could get a shim that was .003 (3 thou.)
If the heads were milled .003 and a .030 shim were installed, the pushrod would probably flop out of the socket in the lifter or rockerarm and jam up on something??
just thinking,
Rick
 
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