what thermostat
 

got a 350 merc. in my 23xl wellcraft nova. calls for a 142 if runnig wide open. an 160 if crusizing my questions is what one should I run and how big a difference between the 2. I do mostly crusing, some wot. Im looking an changing over to a edelbrock perfomer rmp intake.

All the carb engines came with the 140 deg when they changed to fuel injection they started using 160 deg. The actual temp on the gage may vary.

its qudrajet 4 barrel so i guess ill run 142. i had a 160 in there as of last year.

Was your alarm going off. When I intalled my aftermarket MPI kit I started using a 160 deg therm. My alarm kept going off for the temp being too high, so I installed a temp switch from the 454 Mag MPI engine.

no it always ran around 160. only if i ran wot for 20mins it would move up to 165 to 170.