GEN 2 anyone running a 170 thermostat?

[dhmcfadin]

I replied to this thread when it was first posted, but I see it has flared up again this year. I have an SPD 170 tstat, Full Race IC, MPT 93 PRX tune, cooler spark plugs and the nGauge mounted on my dash displaying temps, among other things. Over the last year, my coolant temps rarely goes above 190 and my IAT is typically 20 degrees over ambient. The truck runs cool even when the temp in Houston exceed 100 degrees and I think 170 tstat was cheap insurance for my build.

Yup! Nice setup by the way!

 

[HeavyAssault]

Is the rated tstat temp (170*F for this topic) the "fully open" temp or the "start to open" temp??

 

[dhmcfadin]

Starts to open about 160. My truck runs about 180-190 in Texas heat.

 

[HeavyAssault]

So getting the electric fans "programmed" to come on earlier wouldn't help lower the temps to peoples liking using the OEM tstat??

I say "programmed" as in using either ForScan or the IDS to get their settings set for the user. Seems as there is the fan control ability thru getting aftermarket tuning so I'd say it can be done on OEM files just not sure what tool people would use.

 

[dhmcfadin]

So getting the electric fans "programmed" to come on earlier wouldn't help lower the temps to peoples liking using the OEM tstat??

I say "programmed" as in using either ForScan or the IDS to get their settings set for the user. Seems as there is the fan control ability thru getting aftermarket tuning so I'd say it can be done on OEM files just not sure what tool people would use.

I have a datalogged tune and the fans are set to coordinate with the cooler stat. Temps are about 190. It’s not so much engine temps that you should really be concerned about. More EGT’s. A pair of SPD turbo adapters will do wonders.

 

[hedonist222]

Lots of misinformation in this thread.

A cooler thermostat is not used to make the operator feel better by looking at a smaller number on a gauge. A cooler thermostat is used for the following reasons. Each is individual but they all work together.

1. Cooler EGT’s due to cooler block temperatures. HUGE for a forced induction motor. Why do you think the diesel guys watch their EGT’s religiously? The compression of air generates a tremendous amount of heat. You can easily cook a set of pistons or valves by not keeping EGT’s down.

2. Cooler block temperature allows the truck to run more timing thus making more power more efficiently.

3. When racing or baja or even driving hard, temperatures can easily see 350+ degrees in certain parts of the block. This is extremely common. With the stock 195 thermostat, it opens at about 190 and sets the truck to run, during normal driving, at about 210. Go do some mock 1/4 miles runs or 0-60 or WOT driving. You will see that 210 ping 250 easy depending on how hard you push the truck. In other parts of the engine, that number is significantly higher. With the 170 degree stat, it opens right at 170. Right off the bat, you have a 20 degree buffer to help curb those extremely high block temperatures and EGT’s. Heat is the ultimate enemy for any internal combustion engine.

It should be obvious that with a cooler thermostat on a fuel injected turbo engine that a tune should always be used. For those that say a cooler stat does nothing, they are just not fully informed. Ultimately, a cooler stat on a forced induction motor is pretty much a must if you want your engine to have some type of consistent power across different environments and temperatures.

Another way to significantly lower EGT’s even further is to run larger turbo adapters but this post is about thermostats.

For sake of discussion, if this was crucial to engine life, wouldn't Ford have included it as stock?

Especially since they offer a 5 year warranty. With a 170 thermostat, they'd effectively be saving themselves millions in warranty repair, aside to reduced brand loyalty.

 

[Gsteve]

Emissions.....

 

[dhmcfadin]

For sake of discussion, if this was crucial to engine life, wouldn't Ford have included it as stock?

Especially since they offer a 5 year warranty. With a 170 thermostat, they'd effectively be saving themselves millions in warranty repair, aside to reduced brand loyalty.

“When running a tune”

 

[hedonist222]

So getting the electric fans "programmed" to come on earlier wouldn't help lower the temps to peoples liking using the OEM tstat??

I say "programmed" as in using either ForScan or the IDS to get their settings set for the user. Seems as there is the fan control ability thru getting aftermarket tuning so I'd say it can be done on OEM files just not sure what tool people would use.

No
Because the fans would be cooling nothing but an empty vessel.
The stock thermostat sends coolant into the radiator after 190.
What will the fans be cooling when the thermostat hasn't opened and redirected coolant into the radiator?

 

[RobertH6657]

As I understand it, the Raptor has 2-speed electric fans for radiator cooling. When you are driving down the road at speed, the fans shut down (unless the ECU steps in to turn them on), your radiator louvers CLOSE to increase gas mileage, and the airflow across the vehicle/radiator does all the work. The engine maintains temperature at, or just above, the thermostat rated temperature. If you're towing, or hauling a heavy load, or it's super hot out, or you are in stop and go traffic, the temperature is going to go above the thermostat rating for sure, then the 2-speed fans kick in at different temps to cool the engine. The whole purpose of the 170F thermostat is for improved performance. It's not to save the engine, or make it last longer, or to make the engine more fuel efficient. If it did those things, FORD would install it from the factory. Hot rodders like to race from light to light, or at the track when you are starting from a dead stop. Try sitting at a light in the middle of Summer and watch your temperature gauge. It will go to 220F or more. With the 170F thermostat, I am in the middle of Summer and my fans are full ON at 175F keeping my Raptor around 190F(ish). When I hit the gas, I guarantee you (all other things equal), that my Raptor will generate more boost and advance the engine timing further than the Raptor that has the original 193F thermostat in his/her truck. That's the point of the thermostat. Same thing at speed - the 170F thermostat Raptor will generate more boost and advance the timing than the 193F thermostat Raptor. And for $50, its WELL worth installing it. However, as someone stated earlier, you MUST have the ECU programmed so that the fans are programmed to turn ON at 175F(ish) so that the engine will stay at or near 170F when stopped or in traffic, etc. If you don't reprogram the fans, the factory setting won't turn the fans ON until your engine hits 200F(ish) defeating most of the purpose of installing the 170F thermostat. The difference in HP (all things equal) is substantial due to the way FORD has these Raptor motors super sensitive to knock on both banks of cylinders - and they massively reduce the timing spark.