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Btw what is the vacuum advance?
Here's hoping that your new old school mechanic has been able to help you out!
He will have noticed the lack of the vacuum advance as well - the vacuum hose that attaches to your distributor.
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On performance engines vacuum advances are rarely used. Typically you run as much initial timing and mechanical advance as possible for performance. If there is any timing remaining to get to the total advance you want then add the use of the vacuum advance.
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Well folks. Thank you all for your advice. Turns out it wasn't the headers leaking. Turns out it was.....just about everything in the top of the motor. Valves were stuffed (several of them) and leaking and not closing off and damaged. Roller rockers were stuffed - several of them (from bashing around with the valves). Push rods were worn. Lifters were worn.
So a few $ later. Actually a lot of $ later and its running like a charm. Guess i'll tackle the bottom end another day I'll post up the new sound soon.
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I am glad to hear you are back up and running!! It sounds like the first mechanic didn't do such a good job setting the valve lash. Based on the damage you described it is possible the incorrect push rod lengths were installed which changed the entire geometry of your valvetrain. Out of curiosity what was the reason why the mechanic installed new push rods and guide plates to begin with?
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(05-29-2019, 07:07 PM)Mustangmike Wrote: I am glad to hear you are back up and running!! It sounds like the first mechanic didn't do such a good job setting the valve lash. Based on the damage you described it is possible the incorrect push rod lengths were installed which changed the entire geometry of your valvetrain. Out of curiosity what was the reason why the mechanic installed new push rods and guide plates to begin with?
He decided they were wrong. ?. However I don’t believe he was totally at fault. Inonly drove the car a about a dozen times on short trips since he did the work. I believe he didn’t help but the new guy showed me just how wrecked the valves were. Really bad. So must have been a problem for a while. He said several weren’t closing. Yeah all bad. But anyhow. All running strong now.
Fingers crossed.
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The fault can be placed on the solid lifter cam. Solid lifter cams will damage stock rocker arms and valves. With solid lifter cams, todays norm is using full roller rocker arms and valves with hardened tips. Many years ago, lash caps were installed on the valve stem tips to prevent damage to the valve stems.