I used a brass t with 2 brass barb fittings on the other side I place my sending unit. The whole thing cost me less than $10. Its out of the way and reads the temp good.

 

is that from an outlet off your RAD? if so I think its better to have the temp before your RAD to get a 'true' engine water temp reading instead of the radiator water temp.

Dunno, I could be wrong

 

The outlet from the Rad. is the same one that you would run off of your AST (lower center) and the same for the upper hose near the rad. cap.

Its a cheap and easy install, plus the where to get the"true" engine temp is always up for debate.

 

If that is the outlet after the radiator, it is a really bad choice for a sending unit. If you don't want readings as hot as you can get, why not hook up to the wiper fluid reservoir

 

IIRC there was debate about the TB coolant line vs. thermostat housing, but not the lower radiator hose. Why do you want to know how well your radiator is working?
It's hard to get any easier than the TB coolant line.

 

Yep!! I tested the temp readings from TB coolant line, and t-stat housing. They were nearly identical. Since the TB coolant line is so easy, and it gives readings ALL THE TIME, it is the best spot for a sender

 

Do you really need to place the sensor at the hottest point in the cooling system?

As long as you know where the sensor is located, and know what the "normal" operating temps are with the sensor located in that location, then I don't see why placing the temp sensor before/after the radiator really makes a difference. You'll still be able to spot abnormal temps and shut the car down.

Edit: I'm in the TB coolant line (my temp sender that is)

 

Yes!!! You should always strive to do things right. Doing things right will result in less chance of a screw up.

Example: 4fun loans his car to "Bob", and forgets to tell him that he installed the sender in a spot that will give accurate readings. Something goes wrong with the car while Bob is driving it, and the temp gauge goes to 225. Bob knows that 225 is ok, so he continues to drive the car, which is really at 250 degrees. The car overheats for an extended time, and the coolant seals are toast, along with whatever else melts with them.

 

no it's not. right underneath the thermostat on the engine side...that's where coolant temps are the highest.

 

thermo housing it is. didn't even cost me anything but a tap. easy as hell. people shouldn't be scared to drill and tap the thermo housing, I found it to be very easy and that is for someone at the time that had very little tap experience. You get exactly the same spot as the stoock sensor, that way you can really see how the stocker doesn't work. I am up to 140 on my defi before the stock one even moves. I vote to do it right and rest assure your getting proper temps. I think its worth it, don't you?

 

The stock sensor is not after the thermostat. I agree that you should do it right, to get the right readings.

 

I agree, but I don't. Well I certainly agree with the do it right part. Just not with the example (because I would never lend my car!)

Don't know why I'm arguing though, given that I would never install my temp sender there. The TB is so much easier. If I was to go for an alternative for the TB line, I'd tap the thermo housing.

 

Bad example....your first screw up is letting someone else drive your car ! ! ! LOL Besides no one looks at the gauges or the lights when they come on.

 

Just to point it out. It's in the line that would normally go to the AST. In his case it seems that he has eliminated the AST and the line goes straight to where the AST would go into the rad. It should in theory read just about the same as having it tapped into the housing.

 

As it does.

I guess we all have a "right" way going about placing there sending units. At that location works best for me. It works and I know if I have a temp problem. Thanks for the input guys. What I will do is write down my reading there and then barrow another sending unit and see what the diffrence is + or - .

 

There is a drawback to looping the line from the fillneck to the radiator instead of capping both sides. It allows hot coolant to bypass the radiator.
The stock AST actually has a restrictor built into its outlet so that the volume of coolant flowing through it is significantly reduced. I think it's something like 1 or 2mm in diameter, very small.
An unrestricted 10mm will actually flow a significant volume.
Just something to think about.

 

Ya, I didnt think about that. Ill find something to neck it down a bit.

 

although you're right about that, if you have to worry about that, your cooling system is inadequit.