I read that recommended drill bit for 3/8 NPT is 37/64 and alternate size is 9/16. In mm it's 14.6844 and 14.2875, so my plan is to get 14.5 mm drill bit, 15 will probably be too much )
Living all my life in metric part of the world, fractional inch sizes are a bit confusing
. Not saying that I had to order 1/8 and 3/8 thread taps and wait for three weeks for them. Anyway, most of good and affordable aftermarket stuff comes from USA, so there are no other options )
I tried to put the manifold on top of the engine and it looks that sensor can be mounted on the bottom. Here:
Just enough room to get it in and out with manifold installed and I can't see any problems with the connector as well. Probably will be easier to tap because manifold is flat there. But I still want to try spot on the top. I believe it's the best spot in terms of airflow although wall thickness and rounded shape may require welding the bung in...
By the way, here are my sidefeed fuel rails and rest of fuel system parts:
Definitely an overkill for my stock yellow injectors and expected power levels, but should be fun learning experience. Always wanted to do something with AN fittings )))
Probably should have gone with top feed conversion, but rails with most of AN stuff appeared on ebay in Europe as a kit with nice price tag on them. I think I'll still be able to find bigger side feed injectors If I'll need them someday...