GEN 2 anyone running a 170 thermostat?

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baugustine

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With all due respect to you guys making comparisons to big-bore diesel tuning, the OP was asking about installing a lower temp thermostat. No one was providing misinformation when advising him to save his money. He did not say he was building a desert race truck. If he’s planning on making lots more horsepower he’ll need much more than a thermostat and a tune. A complete analysis and upgrade of the cooling system would be necessary, including flow rates, radiator surface area and thermodynamics. These motors are very different from a Cummins or Powerstroke, including expensive catalytic converters that don’t like high heat or overfueling.
 

Lonestar608

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baugustine, you mentioned that sitting on I-10 in the middle of summer would be a different use case. For those of us that live in Houston and deal with this use case regularly, does your opinion on thermostats change? Are there other upgrades/changes/solutions you would advise?
 

dewalt

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My motor was running up to 220. Being old school diesel that looked too high. So I put in a 170. Runs 190 to 200. Fans come on at 190 so it doesn't.t make sense to open thermostat and start fans
 

RobertH6657

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dhmcfadin has it right. I had mine dyno'd at MPT in Longwood 7 times and pretty much what he said is spot on. I examined real life performance differences with dyno charts proving what he shared. If you just drive your truck normal, the thermostat MAY give you a little worse fuel economy (0.5 MPG maybe), because MAYBE the ECU is determining that the engine needs to run richer because of lower operating temperatures. But, remember in my former threads when I fully explained actual HP and Torque numbers I received on the dyno at MPT over the course of multiple (7) runs. The temperature of the engine at each time of the dyno pulls directly impacted the performance output IMMENSELY. The Raptor engine is SUPER susceptible to changes in OAT and IAT. If you PLAY with your Raptor and have a heavy foot, like to race at a local quarter mile track, tow, or live in hot Florida, like I do, then having your engine run a little richer when you nail it, will be helpful for performance. I inspect my plugs regularly (as you guys have recommended) and you can read the color of those pretty easily to see if your engine is running too rich. Mine is NOT running too rich with the stat. But, the key is that it is a VERY inexpensive $50 mod you can DIY at the house and gain more PROs like dhmcfadin shared (and very few CONs) from doing it. If you live up North, maybe you don't really need it, but you also have the great White North climate cooling your OAT and IAT 20-30F lower than us down here in the South. Down here we need to get rid of the engine heat and reduce intake air temperatures (IAT, some call it ICT) as much as possible or we get massive retarding of the timing due to excessive knock/predetonation. Ford uses knock sensors on both banks to pick up signs of predetonation. The thermostat helps on the engine temperatures, a new larger Intercooler would help on the IAT - but they aint cheap. On the Raptor, advancing of the timing = more boost. Said another way, anything you can do to get more timing advance, will give you much more performance.
 

dhmcfadin

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dhmcfadin has it right. I had mine dyno'd at MPT in Longwood 7 times and pretty much what he said is spot on. I examined real life performance differences with dyno charts proving what he shared. If you just drive your truck normal, the thermostat MAY give you a little worse fuel economy (0.5 MPG maybe), because MAYBE the ECU is determining that the engine needs to run richer because of lower operating temperatures. But, remember in my former threads when I fully explained actual HP and Torque numbers I received on the dyno at MPT over the course of multiple (7) runs. The temperature of the engine at each time of the dyno pulls directly impacted the performance output IMMENSELY. The Raptor engine is SUPER susceptible to changes in OAT and IAT. If you PLAY with your Raptor and have a heavy foot, like to race at a local quarter mile track, tow, or live in hot Florida, like I do, then having your engine run a little richer when you nail it, will be helpful for performance. I inspect my plugs regularly (as you guys have recommended) and you can read the color of those pretty easily to see if your engine is running too rich. Mine is NOT running too rich with the stat. But, the key is that it is a VERY inexpensive $50 mod you can DIY at the house and gain more PROs like dhmcfadin shared (and very few CONs) from doing it. If you live up North, maybe you don't really need it, but you also have the great White North climate cooling your OAT and IAT 20-30F lower than us down here in the South. Down here we need to get rid of the engine heat and reduce intake air temperatures (IAT, some call it ICT) as much as possible or we get massive retarding of the timing due to excessive knock/predetonation. Ford uses knock sensors on both banks to pick up signs of predetonation. The thermostat helps on the engine temperatures, a new larger Intercooler would help on the IAT - but they aint cheap. On the Raptor, advancing of the timing = more boost. Said another way, anything you can do to get more timing advance, will give you much more performance.

Just FYI, the tune in conjunction with the 170 stat eliminates rich air fuel mixture. It’s right where is should be. A tune is pretty much mandatory for the cooler stat for this reason. If you truck is still running rich, I would either get a tune revision or switch to 5Star.
 

Gsteve

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i have the tune and the stat... just gotta install it. Still a good mod?
 

zombiekiller

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I get that people sometimes do "mods" just for the sake of messing with the truck, but the tstat thing, unless you are running hard, doesnt make a ton of sense to me.

But if youre a desert rat, do it. also do an IC, do a radiator and do a trans cooler.

you'll need them all.

Also buy a big baggy of extra spring tension clips. They start to lose clamping force once the ambient air temps head north of 105ish. ( ask me how I know).
 

TXRaptor

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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 the 170 tstat was cheap insurance for my build.
 
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