Sup guys and gals. I'm going to be ordering some of my fittings for my build soon, however, I was going to buy some stainless steel ones we use for work, BUT, they only fit up to 12mm tubing in 1/4" size threads; only the 1/2" BSPP/ (F) fit the larger sizes, 16/19mm. So, my question is, if dropping down in tube ID going to cut down on temps, not interested in flow, as it won't drastically change. I was looking at 13mm ID and 19mm OD fittings in the water cooling style, not the industrial stainless ones I use on occassions at work, plus a 18mm compression angle is £80 so thats a big no no! It would cost me over £2000 for the fittings I'm looking at lol!