If your chambers have been worked/cnc'd , you may want to find a way to see exactly how long of a reach plug that you need. I have a set of BB RPM heads in the shop now that have had the chambers cnc'd and because of the material that was removed , the threads for standard .750 reach plug ,for that head, now protrude an 1/8" into the chamber. While I dont think that would cause any clearance issues, it will affect how well you plug will dissipate heat.
So with the plugs sticking into the chamber 1/8 inch, do you just stack washers on the plug to correct the depth? Leaving them long , the threads will carbon up and either pull the treads upon removal or break off the plug. What's it going to be?
