GEN 2 anyone running a 170 thermostat?

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TXRaptor

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I am running a 170 t-stat with my MPT tune and I have seen my temps range from 170 to just over 180. I live in Texas, so having a lot of heat in the winter is not an issue for me. As other have posted, the truck warms up to 170 pretty quick and stays right in the 10+ range for the duration.

Edit: I did mine so the truck would run cooler when it hits 100+ degrees in the summer.
 
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Ruger

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I put a Scangauge on my truck recently and I was seeing temps around 204-210; thought that seemed high although stock temp gauge (no numbers yet) seemed normal. is that the stock setting for GEN2?

The stock thermostat is a 195 degree unit. Those temps are what I see on my Scangauge, too.
 

zemuron99

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I’ve been running a 170 for about a month now. I was tired of it running 220-235 degrees. Just seemed if it ever started to overheat for whatever reason, that it was just too close to bad crap happening.

Now I’m running about 180-190 degrees with normal driving. I’m running the MPT tune, though it’s not really a necessity. I have seen zero bad effects from running the 170. Still warms up just as quick and still get good interior heat. The stock one running so hot was just to please the government. So screw them.

I am running a 170 t-stat with my MPT tune and I have seen my temps range from 170 to just over 180. I live in Texas, so having a lot of heat in the winter is not an issue for me. As other have posted, the truck warms up to 170 pretty quick and stays right in the 10+ range for the duration.

Edit: I did mine so the truck would run cooler when it hits 100+ degrees in the summer.


Swarfworks, couldn't agree more. The stock unit just seems to leave too narrow of a window between 'normal' and 'getting a little warm here...'.

Questionfor you and TXRaptor : Did you do the t-stat change yourself or have a shop/dealer do it? I'd like to do it myself, haven't yet run across a good 'how to' video or set of instructions. I'm reasonably handy with tools and know my way around an engine (did a supercharger install on my Tacoma many yrs ago). But want some guidance here. THanks.
 

TXRaptor

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Swarfworks, couldn't agree more. The stock unit just seems to leave too narrow of a window between 'normal' and 'getting a little warm here...'.

Questionfor you and TXRaptor : Did you do the t-stat change yourself or have a shop/dealer do it? I'd like to do it myself, haven't yet run across a good 'how to' video or set of instructions. I'm reasonably handy with tools and know my way around an engine (did a supercharger install on my Tacoma many yrs ago). But want some guidance here. THanks.

I had mine done at the same time as the rest of my build by the shop. He said it was not difficult other than the anti-freeze mess.
 

RobertH6657

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The 170 Thermostat theoretically should provide some substantial HP improvements because the engine should be able to advance the timing further (and spark) at higher turbo boost levels with less knock (which retards the timing). The Raptor is one crazy truck and like it or not, it has one of the most inconsistent performance engines out there. I had my 17 Raptor dyno tested at MPT in Longwood, FL seven times. The engine, when warm produced over 50HP more than when it was at normal hot operating temperature. It produced best when engine was coolest. This was due to a number of factors, but the two biggest factors were intake charge temperature and the other was the temperature of the engine. Stock thermostat is 195F. To allow the Raptor to create the most HP and Torque, you need it build the most boost pressure, while simultaneously keeping the timing advancing as much as possible. The reason the engine retards the timing is your knock sensors pick up predetonation. When this happens, the knock sensors immediately tell the ECU to retard the timing and your engine loses big power and your boost drops. Predestination occurs because too much heat is in the cylinders. How do you reduce heat? Lower the temperature of the engine via a lower 170F temperature thermostat, 25F drop is substantial! And put on a larger intercooler to reduce the intake charge temperature. Higher octane gas is also a big help but 93 is about all that is commercially and reasonably available in Florida. The question on these thermostats is has anyone tried to put one on themselves? It's not real simple because all the aftermarket one's on the street are 64mm in height. Stock is 61mm. That's about 1/8" taller. When you put it in the water housing, the stat hits the back of the housing and in order to get the stat on you have to push the spring down compressing the stat. I don't understand how this impacts the water bypass if the stat is pressing against the housing but it does not seem right to me? Has anyone put in a SPD Performance 170F stat, or any other stat? Did they experience the same issue? Any feedback is greatly appreciated.
 

RobertH6657

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Cooler temperatures are much more important on turbo and supercharged vehicles due to the amount of heat generated through compression of air. On the same day when MPT dyno'd my 17' Raptor we had Rear Wheel HP differentials that varied by nearly 75HP (that's nearly 100 HP at the engine!!) This was only attributable to whether the engine was hot or warm or cold when we did the test!! I was there and watched it. That tells you just how sensitive the Raptor is to temperatures. MPT said don't waste your money on aftermarket add ons except for three things because they tried everything out there including cold air intakes, exhaust, etc. The three things that made the most significant improvements were the 1) the nGauge with the Tune, which took mine to 398 HP and 445 ft-lbs torque at the rear wheel 2) the 170 thermostat, which I still can't figure out how to put it in and 3) the larger Intercooler (future). Everything else proved to be minimal gains and not worth the money. Not my words, theirs. When stock, my cold run before we tuned it was by far the best HP and Torque output of the three runs we did when stock and it was only 339 HP and 354 ft-lbs. We couldn't even get 300 HP out of it when it was hot because the ECU kept retarding the engine. Crazy!! These are rear wheel figures, not at the engine.
 
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