I think I have found another controversial topic like 'Which Oil to Use'

[BRENT in 10-uh-C]

...and it goes something like this. What is the proper length a replacement one-piece valve guide is supposed to be exposed (protrude) from the valve guide bore?

This should be an easy topic to determine. The replacements one-piece guides are roughly 2-¼ (2.2500") inches in overall length. The original guides have an overall length of 2-⁹⁄₆₄ inches (2.1400"). The original guide has a shelf located approximately 1.3000" from the top of the guide that locates each guide to a uniform height. So where does the ⁷⁄₆₄" difference between the guide lengths go?

Should the replacement one-piece guide;

..... ◆ -protrude upward into the port area by the 0.110" potentially impeding airflow yet adding more stability to the valve stem.

..... ◆ -protrude downward into the spring area,

..... ◆ -split the difference making it protrude 0.055" higher than stock, and 0.055" lower than stock.



Bonus round question, how much valve seat spring pressure is lost when the 0.1250" thick guide shelf is no longer used? (I think you will be surprised.)

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