best place to add water temp sending unit for aftermarket gauge?

Jwood562

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I so I am adding couple basic gauges, water temp being one.

what is the best place to add the sending unit? I am looking for a very clean OEM looking (or hiding) install and the most accurate place to get a reading.

I have only seen the splice in upper radiator hose adapter. I dont really want to splice my mishimoto radiator hose up top.

can i drill and tap the thermostat housing?

If I have to splice a hose, can it be the lower? or the one that runs to the coolant tank, those would be easier to hide
 

JC SSP

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That would be the perfect place for a temp sensor.
 

Jwood562

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You could drill and tap into the coolant crossover.

that is a great spot, but i'm not sure i want to pull the intake manifold to drill and tap the crossover.

I still make check the clearance on top of thermostat housing.

any other suggestions?
 

bambam 06

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that is a great spot, but i'm not sure i want to pull the intake manifold to drill and tap the crossover.

I still make check the clearance on top of thermostat housing.

any other suggestions?

It will not fit on top of the thermostat housing, it will hit the hose coming out of the intake manifold. I tried, you have to do it on the passenger side next to the alternator bracket. You need a 1/8"-27npt tap and a 21/64" drill bit. I just did it last week.
 

bambam 06

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bambam 06

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Auto Meter electric temp gage Z series #2635, auto Meter sending unit #2258.
 

Jwood562

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It will not fit on top of the thermostat housing, it will hit the hose coming out of the intake manifold. I tried, you have to do it on the passenger side next to the alternator bracket. You need a 1/8"-27npt tap and a 21/64" drill bit. I just did it last week.

thanks for your input and pics. i am using glowshift gauges and the sending unit is low profile.

me being a glutton for punishment, i think i can make the housing work. and if i cant, im out $25 for the housing i bought. i would rather experiment on easily replaceable housing parts. I bought a new housing at a local parts shop, which appears to be OEM as it has the same markings and casting marks.

the water cross over is still the most ideal place, but my thermostat housing experiment should work and serve others well
 
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Jwood562

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so a little experiment update, I took the new housing and marked where i wanted to mount the sending unit, I decided the very back that goes under the intake manifold, there is a good spot, if you get the hole straight.

I tried my best to gauge the housing thickness to see how many threads i could create. I think I was wrong, once the hole was drilled, I tried running the tap and could not get it to cut clean threads. for two reasons, the housing was too thin and it was on a rounded part of the housing.

I planned for this.... I bought a $5 aluminum 1/8 npt weld in bung. opened the hole to the bung specs and now have it ready to go in. Im going to JB weld the first one and install it, it if works and I want to make it "better" I will have the bung tig welded on my OEM one
 

Reloader

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308446350_502294635010216_2736893849430103303_n.jpg I'm sorry for the poor picture, I should have looked more closely.

Yes it is. I have an Autometer 100-250 Water Temp Gauge wired directly to that point. Kit came with sender. It will read lower than the temp that comes from the stock sender because the stock sender is located on the passenger side head under the intake manifold. The stock sender actually reads head temp rather than water temp.
 

wdrlaw

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It will not fit on top of the thermostat housing, it will hit the hose coming out of the intake manifold. I tried, you have to do it on the passenger side next to the alternator bracket. You need a 1/8"-27npt tap and a 21/64" drill bit. I just did it last week.
Sorry I'm a little dense and late to this party. So to tap into the crossover manifold you need to remove the intake and remove the crossover, drill and tap for the sender, and reinstall?
 

Reloader

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I have the new version crossover pipe on a '05. The driver's side of the crossover that is on my engine has a threaded plug. The prior owner installed the cross-over, removed the plug and installed the Autometer sender and gauge. One wire through the firewall to the gauge.

Look closely at the picture and you can see the plug that I am talking about.

s-l1600.jpg

Hope this helps.
 

TexasBlownV8

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I have a 05/06 crossove I drilled/tapped, and used for quite a few years; removed and listed in parts for sale on here, but here's what it looks like:
one hole used for temp sensor (1/8" npt), another with 1/4" npt.

crossoverinstalled.JPG

crossover-tapped.JPG
 

wdrlaw

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My car is a 2009 GT. The crossover manifold does not have a hose outlet per se; the thermostat drops in on the driver side, covered by the thermostat housing, and the upper radiator hose attaches to the housing. I can tap into the passenger side pad as Dino Dino Bambino and BamBam06 suggested. I can't figure out how to avoid metal drill or tap filings getting into the coolant passages (or removing them) without disassembling the intake and crossover and drilling the tap on the bench--something I would prefer to avoid. Also, I have Mishi's pricey radiator hoses and don't relish the thought of cutting them up. So, I guess the driver side block plug is my remaining choice?
 

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