I appreciate the explanation of exactly why this is important. And not just telling us we have to do it

Telescope gauges (he refers to these as "snap" gauges) can be highly accurate for small bore measurements. It all depends on who's using them and how experienced they are with this tool.

I can build the heck out of an engine but every time I watch one of his videos it’s a reminder I’ve been doing it wrong for years lol thanks for all the help love to see more.

Excellent explanation & I learnt something new. Cheers

Great stuff!

Thanks for the education. Cheers.

I am struggling to find the link you said in the video for the micro set

Curious, when you try to "Narrowest point"... is that typically when the needle goes counter clockwise or clockwise? I'm trying to figure out wheres the 0 position if i were to rock it back and forth. I might be confusing myself. I'm sure the answer is when the needle goes backwards/past the 0 mark going counter-clockwise then zero out the gauge by moving the dial and recheck to redial the measurement... at your 6:13 clip, i'm guessing the above was too confusing. So pretty much its either the minimum to highest point in the needle reading and choose where you want to zero it out at and remeasure how far it move and that's the varying clearance between the bore. I love your engine building tips. Keep this going!

An excellent video, but I believe misses some important information the at home or inexperienced engine builders need. Most engines/blocks the viewers are working with are used, and the bronze bushed or enlarged lifter bores are out of budget for them. Flat tappet lifters can be used in bores with as much as .003" clearance with a little extra (and simple) work to the block. Usually what causes flat tappet lifter failures IS lack of rotation, but because of another issue not mentioned. The bottom of the lifter bores see the side loading as lobe pushes the lifter up, the very bottom edge of the lifter bores will dig into or bind the lifter enough to keep the lifter from spinning and wipe out the cam and lifter(s) Flip the block upside-down, and with 800 to 1000 grit "wet-or-dry" sand paper and a light oil - automatic trans fluid works fine - polish the sharp edge of the lifter bores off. Just take that sharp edge off, that's all that needed, just enough to take that very corner off. This will keep the lifter from binding and let the lifter spin. Actually this should be done on new freshly machined blocks also - even on roller lifter applications because that sharp edge will score and gouge the lifter and cause more problems later. Another common reason for this kind of lifter failure comes from having a block baked and blasted at a shop. Most shops use beads not sand to blast the block clean, the problem comes in that the beads will roll the edge of the lifter bores towards the bores - unless this metal is removed it will also cause the lifter to bind or drag in the bore, or at the least gouge the lifters. We've been in the race and/or street engine service field for some time and have not had a flat tappet cam failure yet, so I know this information works. Otherwise a Fantastic video, and well explained!

I learnt something new😀.

The telescope gauge is a very accurate method. To use it properly one lets is spring open, one then snugs (not tighten like no tomorrow, just snug) the screw and rocks the telescope gauge over "top dead center" to explain what we would be doing, this gets the telescope gauge right at the hole size. I think if you practiced a bit you would quickly see how accurate it really is :-). The downfall of the telescope gauge and even the dial bore gauge is that they do not tell us exactly what size plug would fit in the hole due to the hole not being perfectly round :-). This is true of any 2 point measurement.

What would happen if I put a roller lifter set on a hydraulic flat tappet cam? Obviously would need set with links like u showed

Are flat-tappet lifters that have the small oiling hole on the face, a worthwhile upgrade?

Comment on the practice of grooving the lifter bore to increase oil lubrication to the camshaft.

Telescopic gauges are incredibly accurate, you just don’t know how to properly use them. You have to “snap and snug”, then drag across center to find the largest spot. The plungers will will find the biggest diameter, shock you then measure. I think 80% of the people I’ve met do not know how to properly use those measuring tools. I’ll add that cam tunnel index is as critical as lifter bore position.

Maybe I missed something but why the hell would you go to a bigger bore Ford or Chrysler lifter which also have more mass? Isn't that just adding mass to the valvetrain and causing problems?