valve guide wear
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Joined: Mar 2018
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valve guide wear
Im troubleshooting my 1985 corvette rough idle problem- I suspect the valve guide may be worn for the following reason- at some time in the past, some previous owner did lots of engine mods trying to squeeze more horsepower, among the mods were 1- aluminum heads from edlebrock that don't fit right because they have the 2 center bolts at the upward angle- so they elongated the holes in the manifold to make it fit.. 2 they installed a roller cam and roller lifters (which I have removed and I have them listed for sale on face book market place).) 3 roller rockers which I decided to keep. in the process I discovered that after they did all that they didnt bother to get the correct length of pushrod to meet the new equipment and they apparently simply reinstalled the original pushrods which were way to long. and the rocker arm geometry was way off. I have been told that this can lead to valve guides being quickly destroyed. My question is- even with the roller rockers installed, will bad geometry destroy the valve guides?
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Joined: Jul 2003
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From: Saratoga Springs NY
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If the geometry is that far off, usually you will break rocker arm studs. But yeah, its gonna screw up the valve guides as well. A leakdown test would confirm that.
Get the correct length pushrods and set it up. Maybe you got lucky and they are OK.
As far as the center holes being elongated, I've seen that before and never caused an issue. But I've seen it only 2x so....
Get the correct length pushrods and set it up. Maybe you got lucky and they are OK.
As far as the center holes being elongated, I've seen that before and never caused an issue. But I've seen it only 2x so....
