EDIT: This is the passenger side switch used for fan control.

It's been a while since I tried to source one of these. I don't even recall or have records of what I've been using other than to think it was an OEM part in some application.
The image below is what it looks like although the spec is not the same.



That's a Hypertech switch which looks to be unavailable.

I'm looking for any single switch that'll work in or around 180°.
The connector doesn't really matter but a switch with a stud would be preferred as it would tighten up the connection that's right between the header tubes. The plastic version above doesn't like the heat.

Maybe something like this?



https://www.summitracing.com/parts/bci-75029

Anything else?

Thanks in advance.

 

Are you referring to the temp sender to the dash gauges? the one that is on the drivers side of the engine block closer to front? If so, I took a quick look over at RA but it looks like they are all blade style connector. probably a redesign so the connector doesn't get accidentally knocked off as easily as the original factory style.

https://www.rockauto.com/en/moreinfo...=1482&jsn=1482

 

Sorry. I should have specified. This is the temp switch located on the passenger side. It's used for fan control. This all retro-fit stuff. Aftermarket everything more or less.
I've edited my post above (and title) to reflect the change.

I'll nose around at Rock Auto though. They may have a generic listing from Standard Motor Products or similar.
Thanks.

 

Most of what you will find will be like what you have shown in post 1. If you fold the wire back towards the block and zip tie it it will be header friendly. I have tried several. I have not found one that turns on & off at the advertised temps. One turned the fan on before my 180 thermostat opened so it was always on. Others turned the fan on well above advertised temp. 220+. The one I have now turns the fan on at about 225 and shuts off at about 190-5. Of course I've tried so many I don't know which one I am using now. Sorry.

 

I find it's the connector body itself that can't take the heat. It's very bulky and has no place to hide.
As for the many and varied aspect, I agree there's no telling what you'll get despite the rating.
FWIW, between the existing switch in the right side head, the water temp gauge, which is an Auto Meter with an Auto Meter sensor in the left side head and my Dakota digital temp controller, (which is fed from the same sensor as the gauge) , all seem to reconcile at the temperatures indicated or specified. With a 180° thermostat, IIRC, the fan comes on at 195° and off at 180°. (But I may not recall correctly!). At highway speeds, the engine temps stay slightly above the t-stat temps but below the fan switch temps. This keeps the fan off while cruising. If I knew which switch I was using, I'd get another and deal with that bulky connector with some heat shield sleeve and zip tie it out of the way as suggested. The switch itself has had the ceramic bit smashed up (hence the needed replacement) and along with the melted connector body, connectivity is kind of sketchy.
Still looking...

 

He wants a Thermostatic (Electrical Switch to ground) to activate a Fan Relay.

I have used those Stanless Units that you posted (With a sealed up Eyelet) and just wire on a GM Sealed Connector after few Inches.



But I rarely use Thermostatic Switched anymore... Now using Holley EFI with a Temp Sensor and 3-Way Connector:

 

If you want the Stainless type...

I'll wire you up one with High Temp Wire Protection:

I boot the Switch... Raychem Sleeve the Wire, than Fire Sleeve it in 1/4" sleeve:



I would add the connector a few feet away from the heat

 

I haven't located the appropriate switch at this point (although I can't say I've tried all that much).
The idea of a studded switch appeals in that I can complete the connection with little more than a ring terminal and heat shrink. It'll last between the headers tubes. I've also sleeved a couple of single wire sensors (engine and oil temp gauges) with stainless steel thermocouple armour. It's not designed for the application but it certainly is bullet proof.

 

I have multiple levels of solutions that will work, Guarantied!


I'd be happy to take care of you>


Will say that I very much dis-like the Cylinder-Head Location for the Switch for multiple reasons.

I prefer an aggregate of the Coolant/ Water Temp below the Thermostat, over on poor location on one Head.

Please send me Images of the Engine, and the Intake-Manifold Water Ports please!

 

Connectivity and heat resistance aside, do you have a recommendation for a single wire switch regardless of connector type?
195° on. 180° off.

 

This is the closest to what works on all levels. Single stud. Looks to be the right temperature range.

https://www.summitracing.com/parts/cim-p-195

 

Why do you want the Temp set so high?

I recommend a 185 On/ 165 Off from SPAL

I Prefer this Stainless 2-Wire Version (No Eyelet needed) but you have to ground one Wire and run the other Wire to the Relay.
The bad news is it is Double the Price of the type with the Threaded-End and Nut (SPAL #185-2TS) ($59 My Cost).


For a Single Wire version (SPAL #185-TS) ($29 My Cost):

 

The Be-Cool Part in the Link in your 1st Post is a relabeled SPAL 185-TS (185 ON/ 165 OFF) Sold at Cost.

That was a very good find


That is what I pay for them from SPAL.

 

Good question and that spec was some memory of what I had run.
But, it's a 180° stat. After a good heat soak, whether trackside or cross country, temps tend to stay in the t-stat opening region. I like the fans to be off when there's enough breeze through the rad to keep the engine cool. So fan off at 180° works. If I go 170°, I'll never see it. Once the thermostat opens, it'll stay that way. Most of the time anyway.
As I said, I haven't done all of the math. There's the option of lowering the thermostat temperature and then working with the fan switch accordingly. With iron heads and higher compression, 180° was a good go to value. I always managed, other than when I had a temp controller malfunction, to keep in that range.

 

The worst thing for electric Fans is to be switching on and off.

The Fan Start-UP/ Turn on puts the most Strain/ Abuse on the Fan Motor and Amperage Draw on the Circuit.

This is why GM went to dual Fans... Low Speed/ High Speed Circuitry in the 4th Gens.

I try to get all my customers to go this route (Dual Fans with Low Speed/ High Speed Circuitry).
I do not want the fans to ever turn off until the Engine/ Car has been turned off.

To do this, I run a 165*F Thermostat, and I'd rather the Thermostat close, and keep the Fans at low Speed...
Than Fans Off and Thermostat Open.


As an Electrical Engineer, I have determined this to be the optimal arrangement for the life of all the Electrical Components/ Wiring, Etc...

 

Most Fan Companies won't tell you this...

So they can keep selling fans!

 

EDIT

 

ebay has a bunch to choose from: engine fan switch 185 for sale | eBay

3/8" 175~185 Electric Engine Fan Thermostat Temperature Relay Switch Sensor Kit | eBay

Gold 185 To 175 Degree Electric Engine 3/8" inch Cooling Fan Thermostat Switch 813519719154 | eBay

Fan Thermostat Temperature Switch W/ Hexagonal Nut 185°~165° For 265 283 Engines 934067385391 | eBay

185 -200 Degree Electric Engine Cooling Fan Thermostat Switch NPT 3/8" Inch 2PC# | eBay

You will have to look up the specs on these:

Nos - CARQUEST Engine Cooling Fan Switch 77051 769106770513 | eBay

Engine Cooling Fan Switch Standard TS-151, NEW | eBay

Engine Cooling Fan Switch Standard TS121 | eBay

Engine Cooling Fan Switch Standard TS-171 | eBay

Engine Cooling Fan Switch-Temperature Switch STANDARD MOTOR PRODUCTS TS-121 | eBay

 

No Offense @NoEmissions84TA .

I always like your Posts, and respect you here.

But respectfully many of those Products are not very good quality.

I thank you for taking all that time to look all of them up.
As usual, you always put in the time/ work for a good contribution.

Thank you!

 

These Two that you Posted were Great!

#1Link

#2Link

 

Correct - no argument here.
It's a roll of the dice with quality, especially in these times.
USA doesn't manufacture nearly anything anymore, China does.
However, sometimes those "questionable" quality items turn out to be better than one would expect.

And I appreciate your posts and knowledge also. Thanks for being here and sharing.

 

Because the fan would be running constantly...

 

Regarding quality, I installed a switch from Painless (wouldn't work for the O.P. application, as it is a 2-wire unit).
It was rated at 200° On/185° Off. The first two times I ran the engine, it came on at exactly 200° according to aftermarket mechanical gauge.
I was pretty thrilled about this. Well, every time since then, the fan kicks on at 165° or 170°, and never turns off. I later looked at reviews for this fan switch on Summit's website and they were terrible. I guess coming on early is better than late or not at all.
I would actually prefer 200° On/190° Off, because there's no way this engine is gonna run under 190° on a hot day, and I don't want the fan running constantly...

 

I only give recommendations on the Parts I have used over the last 20 Years in my Business.

This is where the Two SPAL Stainless Steel Thermostatic Switch Recommendation came from.
I trust them 100%!

Also...
I Engineer my cars to run 180*F in a 110*F Sunny day in the southern US... if that's what is needed.
I can absolutely do it!!!

 

185 ON/ 165 OFF for the Low Speed Switch and 195 ON/ 175 OFF for the High Speed Switch.

The Fans don't actually switch off.
Just switch from Low Speed to High Speed and Back.
Fans only turn off with the Engine/ Car off.

I want the Thermostat to Close and keep the Fans ON the low Speed Circuit.

The Fans last Forever!!!
The Fans starting over and over and over Kill the LIFE of the Motors.
The Fan Companies do not want you to know this!!!!
They want to sell more Fans after all!!!

 

Well I'm impressed. I've never seen a thirdgen that ran that cool...

 

It takes the Correct Combination of Cooling System Components.

Also as far as third gens go...
Ducting up into the Radiator area is crucial at expressway speeds.

Third-Gens can actually run cooler at an idle, than driving in the expressway depending on how Air flow is directed, and the Volume of Air that can be Captured.
-A Manual Transmission Non-A.C. Camaro is the VERY Easiest to cool.
-An Automatic Transmission with A.C. Firebird is the MOST Difficult to cool.


Front End/ Nose Air Flow to the Radiator is Crucial!
Also I stopped putting Trans. Oil Coolers and A.C. Condensers In-Front of the Radiator...

I design the Radiator Shroud to House the Trans. Oil Coolers and A.C. Condenser behind the Radiator, up against the Fans!


This works far better for Cooling EVERYTHING all together!!!

 

We scared @skinny z away from his own Thread.

 

:'-(

 

Never! What I've learned is that after a certain point in the day, that it's often better to wait until the next day to reply. And seeing as it's now the next day...
I've been saving up for such a reply so here goes.

From day one of building a 3rd gen, it's always been a single OEM fan (no shroud), transmission cooler in front of the rad to one side (spaced by an inch or so), a 180° thermostat and a single wire switch in the right side head. What I don't recall is the rating of that switch. (Dammit!). No A/C.
What I can say is that overheating was never an issue. Under any driving conditions. And there was everything. Stop and go commuter traffic in 100°F ambient, long distance highway, hot lapping at the dragstrip, WOT on a prairie highway and everything in between.

Well, there are two exceptions to that never.
One was when towing a U-Haul behind the IROC across the country. (Yes, the 86 Z had a trailer hitch in the fashion of drag week. It proved handy on our own race weekends when we'd tour the three major dragstrips in southern Ontario and I'll haul the slicks and tools in a repurposed tent trailer. It was awesome.) On that cross country U-Haul trip, I lost the TC lock-up function. As such, I was into the converter stall almost the entire trip. 3500 kms one way. Seldom less than 3000 RPM. Engines temps, even a highway speeds, were consistently north of 220°. Sometimes more. Ultimately, that killed the engine as at the start of the next season it developed a rod knock. Toast!
The other overheating episode, which happened on a couple of occasions, was when my digital temperature controller lost some of it's connectivity and the fan failed to come on. That single wire switch and connector where so beat up that the lead would detach itself from the switch. It wasn't until a scan of the gauges showed soring temps that I'd remedy the situation. This is part of my reasoning for wanting a single binding stud on whatever switch I get. That plastic connector just can't take the heat from the headers.

My recollection of it's operation is that the fan was not always on. Two instances in particular jump out that demonstrate that this was the case.
I've the fan rigged so that I can choose continued operation after the ignition is switched off. I'd pull into a parking lot (let's say) and I'd park, get out and as I'm walking away, the fan would kick-in as now the engine temps are climbing due to the lack of coolant circulation. This obviously indicates that the fan was indeed off prior to parking. The fan would continue to run until the switch commanded it off. This feature was great at the track.
Another instance where I know the fan is off during normal operation is when pulling over to pop the hood after some highway driving. Gauge temps always had me pegged at slightly above the t-stat value of 180°. Something like 185 or so. I'd pull over, do my checks and the fan would then come on after a minute more or less. There again, the rad, which is a Griffin 2.25", 2 row universal fit unit, had enough capacity and airflow to do well enough with the fan.

Now, after having said all of that, going through my as-built parts list (looking for the rad spec) I came across the switch rating that at one time or another that was in play. That was 185° on and 199° off. Seems to me, and I'm going back 20+ years of memory here, is that this was an OEM switch but I can't recall the application. I know that I'd gone through a few of them due to the melting and also from the ceramic portion of the switch getting smashed up during header swaps or similar. I can't say for sure what this latest one is though. Might mean the boiling pot of water and thermometer experiment is in my future.
Looking at those operational ranges indicated by the gauge and Dakota controller, 185 and 199 seem about right.
I can't say at this point whether I'd like to stick with that or cool it down a little.
There also the likelihood of dual fans going in but the need isn't urgent. The additional infrastructure is easy enough to add and the controller I have has a two fan option should I go that route.

Now to determine the best switch for the job. I can't say I'm a big fan of having that one large fan run continuously. If it's not needed for cooling, it might as well just be idle. Any on/off cycling looks to be minor in nature and other than the time that fan never shut of (prior to the digital controller) I've never had a failure. That continuous operation episode simply overheated that aging component.

I'll do a review of the recommendations presented above and try and dial in what I'm looking for.

 

Quality notwithstanding, it looks like Standard Motor Products has the broadest offerings. Reasonably priced too. So much so that, 1) a few could be ordered across a range of temperatures and 2) if they are junk, it's only 10 bucks lost (or about $20 CDN!).
All with a single wire stud for a robust and heat resistant connection.

So, maybe one switch similar to this:


or this:


Combined with a short length of this:

The combined components above could be the answer I'm looking for.

 

I run an RPM Air Gap intake. There are three available NPT ports on the t-stat crossover.
The heater core is piped through the top of the water pump and to one of the ports on the crossover.
All that's available or being used (at the front) are visible in the picture below.




I've often thought about the temp switch location in the head. It is an OEM location though. As in the gauge sensor in the opposite head. I've learned to reconcile those values and have developed a well functioning system. Changes I'd approach with caution however I'm not without wanting to look at the options.

 

All of these are the style you want

 

Thanks.
Have you come across anything in your travels that makes at 195° and breaks at 180°?
It may also be that I'll lower the t-stat setting to 160.
Then I'd lower the switch set points accordingly. Maybe 180 on, 165 off.
It's not so much the highway miles this thing might see as cooling was always very good.
Running laps at the dragstrip in the middle of a summer day was another matter. Still, it rarely saw anything north of 195.

 

I offer these to Most of My customers for Water Temp Sensors, Thermo. Switches, Etc...:



This is Because I usually set up 4-Way, 6-Way, or 8-Way Water Cooling In the Intake-Manifold and Heads:

 

Vortec, where did you find that neat block? You always have the coolest stuff.

 

I've read pros and cons of similar setups. I believe the cons mostly come from disrupting the as designed coolant flow through the deck surface and how and where it mates up with the heads. From my understanding the head gaskets play a significant roll in the coolant management.

 

Slick stuff for sure but readily available.
Never considered one for my application but it would make for an interesting location for the fan switch.
I'd be curious as to what the temperature delta would be between the stat housing and the aft location on the head. At the very least it would require a re-think of the switch set points.

 

I am interested. I would like to keep the A/C controlled fan on when the a/c is on. And have the other fan controlled by your switch. But I have/want a 180 stat. Will I be able to adjust the on/off temps or is that something you do and it's set at that? What kind of on/off range (degrees) can you have? Would you be able to make 190 on/ 175 off low speed switch and 195 on/185 off high speed switch? And how much?

 

Interested to hear the reply too.
Check out the Dakota controller functions below. I think it fits the bill for your application. I bet vorteciroc has something similar in his arsenal.

 

Looking further into what I've got and what I want to do, I discovered, or re-discovered actually as I already knew but had forgotten(!), that I have all that's needed to make it a go in a control sense.
The Dakota Digital Controller can run it all off of the Auto Meter gauge sending unit the LHS cylinder head.

From the PAC-2750 Dakota manual:

Operation
The electric cooling fan controller provides a way to run up to two electric engine cooling fans or one two speed cooling
fan. (A second relay, sold separately, is required for two speed or dual fan operation). The controller monitors the engine
temperature using a dedicated sender, a gauge and its sender, or directly from a Dakota Digital BIM connection. When
the engine temperature goes above a user adjustable set point, the fan is turned on with a relay. When the engine has
cooled below a user selectable off temperature, the fan is shut off. Separate on and off temperatures can be set for the
high and low fan outputs. The controller will also run the fan when the air conditioner requires, by detecting when the air
conditioning clutch is engaged. When the temperature information is provided by a Dakota Digital BIM connection, a high
speed shut-off is also available to disable the fans from turning on once the vehicle is above a user adjustable speed.
The unit can be set to keep the fan running (if the engine is hot enough) after the key is turned off. Several delay times are
available from no delay to five minutes. The display will countdown the seconds left before the fan is turned off. If the
battery voltage drops too low, the fan will be turned off and a “” message will display for the remainder of the time.
Settings for several gauge systems are included to make installation with a gauge easier. The included gauges are
Stewart Warner, Classic Instruments, VDO, and Autometer. If the gauge being used isn’t included, a custom calibration
option allows the system to be calibrated to any gauge with clear numerical temp markings. This is accomplished by
setting the controller to match the marks on the gauge with a few steps described in detail in the installation instructions.

https://www.summitracing.com/search/...yword=PAC-2750

I won't need the original switch in the right side head at all. Sweet.
Unfortunately, for the previous poster, BBCSwap, it's not available, but there are others out there for sure.

I think I may have it sorted out.
Now , as I described in another thread on power distribution, I still want to streamline what I've got now with respect to fuses and relays.

@vorteciroc @BBCSwap

 

PM me with a list of Circuits that you would need put into a PDM, as well as where you will Install it, and where the Battery is, so I know how I will Power it (Cable Gauge, and Length).

 

I'm wanting to know more about it. My battery is on the right behind the headlights. My fan relays are left of the master cylinder. Can I use the OE relay wires to power the PDM and control the fan? Do you replace the coolant temp switch in the right head? And of course approx. cost? $20 or closer to $200?

 

Message sent.