I think this spot should be ideal right where the coolant leaves the block and it clears the alternator. What do you guys think?

 

The throttle body coolant line is easy to access, and accurate. No reason to look elsewhere.

 

From what I understand it reads consistantly 10 to 15 deg cooler.

 

I was using a coolant sensor in my upper radiator hose, right after the hot coolant exits the thermostat housing. This location should have given me the hottest readings once the t-stat was fully opened. Then I installed a second sensor in the TB coolant line. I let the car sit at idle, and warm up. Since I had two sensors, I was able to switch the wires to my gauge back and forth, and check the gauge. The readings were always nearly identical from 180-220 degrees.

The TB coolant line will give accurate readings.

 

+1 This is the most accurate location for the sensor; the stock location and TB lines are OK, but yours is the best, and it's done.

Under no circumstances would I place a sensor placed downstream of the thermostat as it defeats the purpose (of the gauge). Yea, I know that it may seem to work and track, but the gauge temp is now regulated by the t-stat and it will not reflect true coolant temps if the t-stat is closed, stuck closed or sluggish. I know that it's easy to access because of the numerous threaded plugs in the coolant neck, but those plugs are not intended for temp sensors; rather they are coring plugs used to remove the sand mold from the neck during the manufacturing process. The chamber that is formed is designed for air/steam seperation.

 

i have an aem ems that ihook the laptop up to and can monitor the exact degrees of the coolant. i just hooked up a new autometer guage in the upper rad hose as well.....you have to wait about 5 min for the tstat to open, but it was on point with my laptop......i drove the car for 45 min and it was dead on.

 

put my Defi temp sensor in the same spot, it works perfect and doesn't require the thermostat to open before it works correctly. I chose the that location do to a stuck thermostat which cost me a motor long ago. Looks like a clean install, you can also bring the wire up behind the power-steering pump and tie to the stock wire harness. From there i made a small hole in the firewall below the master cylinder, rubber grommet and got the wire up to my pillar mount gauge. Didn't even have to extend the wires. PM me if you want pictures, but you look like your well on your way, good luck!

Mitch

 

how hard is it to tap that for a sensor and what tools / drills / bits are needed?

 

+1 for the throttle body line. SO much more easier. i know its accurate because the stock fans come on at 210. when they come on(not often).... thats where the gauge is.

theres no need to drill and tap another hole in your engine.

 

Thanks fellas, my motor is apart anyway so this just seemed to make the most sense. I'm not big on doing things that are probably ok or almost as good just because they're easier. Thanks for the info though!