I'm thinking for base-plate thickness, you'd be set with something in the medium thickness range... say 3mm min and no more than 8mm... Depends on the flow rate that you're system allows. A nice thick base will act as a buffer for temp spikes or any sudden changes, which should occur if you have a stabil system etc... I'd post my block design, but I wanna post it as a new post so I can get a (hopefully) but of responses/ideas, so see my new block design post... okay, hell, I'll post it here and post a new one etc...
PS- PICK ME!!! lol
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XP 1600+ AGOIA-Y (GreenLabel, UNLOCKED!@/ NF7-S 2.0/ PC 2700 DDR
10.5*172FSB(1806/ 1991 high), Vcore 1.792...@84.95Watts
--86' Chevette Heater Core
--1/2" Vinyl tubes
--Via1300-Stealth Mod(QUIET!)
---Home made copper-tube block
---PVC small internal res