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Old 12-19-2012, 09:07 AM
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Originally Posted by ant_8u View Post
(Regarding valve heights.......since I have pushrods and adjustable rockers, do I still need to concern myself with valve heights?)

Thanks again
The valve height- or more like the depth of the seat- has a direct bearing on the valve spring installed height. Sunk seat = more installed height and vice versa.

So you need to measure the installed height of each valve and shim the springs to give the correct installed height. While there are dial spring height tools, I use a snap gauge and caliper to measure this. The problem w/some dial tools is the top of the tool doesn't always match up to the retainer spring seat, so it has to be shimmed or otherwise somehow account for the mismatch.

No machinist worth his salt will have set you up w/a situation where the seats are too tall, that's to say to give a too-small installed height. But because the new exhaust seats look to be a bit recessed (not that much of an issue especially on the exhaust side), and that the intake seats were refinished (which sinks them slightly) this should not be an issue.

While I certainly understand your desire for perfection, in the greater scheme of things the difference in output between the two different intake valves would not amount to a measurable difference, all else being equal. Not saying don't change them- just saying.
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