Upper would be better.... because that would be the closer to engine temp of the two, but the upper hose isn't necessarily loaded with coolant, so you might get some funky info, and likely no useful info until the engine is fully warmed up.
Really the best measure for coolant temp, is to simply yank out the compensation board in the cluster, which will then liberate the stock gauge so it can give proper, real readings.
Good luck!
-Ryan
--
Athens, Ohio 1987 245 DL 314k, Dog-mobile 1990 245 DL 134k M47, E-codes, GT Sway Bars 1991 745 GL 300k, Regina, 23/21mm Turbo Sway Bars Buckeye Volvo Club
|