cybern8

i am installing a holley sniper2 kit, and need to find a place to install the coolant sensor. the factory gauge sensor already occupies the manifold fitting near the thermostat housing. does anyone know of another suitable location where i can install the new sensor? i already saw posts mentioning cylinder head ports, but those didn't come about until 1968, so i don't have that option. i know i can just replace the factory gauge sensor with the new one and i'll have a dead temp gauge, and i really don't want to do that.

Nowhere Man

in the 70's GM used t-stat housing very close to what was used on mid years but with a bung for coolant sensor

L78

If not the thermostat housing itself, perhss as ps a spacer under the thermostat housing.

but check the fitting port sizes…

jforb

if you put it over the thermostat, it will read cold until the stat opens.

If the heater does not have a water valve in it (coolant flows all the time) you could put an inline bung in the "hot" heater hose.

cybern8

my thinking...
the spacer option (sensor under the thermostat) should give the most accurate coolant temp reading.
the thermostat housing (top) option positions the sensor above the thermostat, and so will be reading the temp of the coolant in the radiator until the thermostat opens.
if i am relying on the coolant sensor input as an input to EFI, it seems the spacer option is the way to go.

sound right?