One accessory that can make a big difference in your gauge readings when installing a diesel pyrometer gauge is GlowShift’s Drill and Tap Kit. Drilling and tapping into your exhaust manifold isn’t necessary for installing any EGT gauge, but if you’re looking for optimal gauge readings directly from the source then using a drill and tap kit is the way to go. This drill and tap kit includes a size R drill bit used to drill the hole for your boost sensor and/or EGT probe and also includes a 1/8-27 NPT tap that allows you to thread your sensor or probe into the drilled hole.
Before you even start the drilling process, it is important that you use a center punch to mark the location where you’ll drill the pilot hole. To install an EGT probe to the exhaust manifold, you will want to drill into the EGT’s turbo flange. As I mentioned above, a size R drill bit is used, but it is recommended start with a 1/8 drill bit and gradually step up in drill bit size until you reach the included size R drill bit. Once you have completed the drilling process, it is important that you remove all metal shavings from the exhaust manifold with a shop vacuum and magnet pen to prepare to tap the hole. Slowly tap the hole to 1/8-27 NPT using the included tap and when you’ve completed this step, remove the metal shavings once more and you’re set! Check out the video below to see the drill and tap kit in action!