170 degree thermostats

[BLKTACO]

Hello,

I’m about to swap in a 170 degree thermostat into my 5vz-de with TRD S/C. I have one now that is the Advance Auto rebranded STANT 14077. This should be the same exact thermostat that NAPA and URD sells. After doing some research I’ve found that STANT has a superstat version part number 46077 which would give you more consistent cooling numbers and more reliability. I’ve also found that a Toyota 90916-03107 for the Carolla should also work. Which I’m leaning towards as they’re way more beefy than a parts store thermostat.

What do you guys run? It looks like most people run the NAPA/URD stat. But I’d like to run the superstat or Toyota thermostat. I’d be a little worried that running a cheap stat such as the NAPA/URD would be more prone to failure.

 

[wemslie97]

I believe the consensus on this site is when it comes to the thermostat, OEM only for quality and longevity. They are pretty inexpensive too. As for 170° or 180° I have no experience although my OEM 180° works just fine. Never see over 190°/193° even on hot days.

Oops, Didn't see the SC part!

 

[BLKTACO]

I believe the consensus on this site is when it comes to the thermostat, OEM only for quality and longevity. They are pretty inexpensive too. As for 170° or 180° I have no experience although my OEM 180° works just fine. Never see over 190°/193° even on hot days.

Oops, Didn't see the SC part!

Yes. I agree for the most part. OEM is better. Which is the reason I started a thread. Of all the time I spent searching for threads on 170 degree thermostats I’ve never seen anyone run anything other than the NAPA/Stant/URD stat. I’ve never seen anyone even reference a Toyota 170 degree stat for S/C. Which got me wondering if I’m over thinking this. Or if no one knew a Toyota 170 was available.

Id also like to know if anyone has had the NAPA/Stant/URD 170 degree stat fail.

 

[wemslie97]

I'm now wondering what originally came with the SC'd 5vz!? Was it before TRD was around? Is there a TRD 170° thermostat for the 5vz? Sorry to pose more questions than answers.

 

[BLKTACO]

I'm now wondering what originally came with the SC'd 5vz!? Was it before TRD was around? Is there a TRD 170° thermostat for the 5vz? Sorry to pose more questions than answers.

1. Toyota never made a 5VZ-FE that came with the S/C. TRD came out with the kit. The closest to Toyota installing was at the dealership.

2. TRD made the S/C kit to be carb approved in all 50 states. They engineered it to be used with stock plugs and no fuel mods etc. although it’s better to cool things down a bit. A roots style S/C heats up the air as it being compressed.

3. This didn’t work for most folks. Although, you can kind of drive around it. It’s better to go to colder plugs, a 10 degrees colder thermostat, fuel/timing mods. As well as a cooler and shift kit for the trans depending on how hard you drive it.

 

[BLKTACO]

I'm now wondering what originally came with the SC'd 5vz!? Was it before TRD was around? Is there a TRD 170° thermostat for the 5vz? Sorry to pose more questions than answers.

It’s cool. I’m hoping some of the S/C guys can comment before I install this Stant 170.

EDIT: TRD made a 160 degrees thermostat that was just a motorad rebrand. And sold it for a huge markup. It’s not recommend to run 160 unless your tune is spot on. I feel better going with 170. I’m running ~200 now (juggle valve is probably in wrong place) so it should bring me down to 180. That should help me tune out the little bit of ping I get in OD and increase my timing.

 

[WVhillbilly]

Why do you want such a low temp thermostat?

 

[BLKTACO]

Why do you want such a low temp thermostat?

It’s 10 degrees cooler. One step down. It’s to help make the S/C more efficient.

 

[WVhillbilly]

I'd be concerned about it throwing the computer a curve ball.
I've had good luck with the Stant thermostats, think they still make a few different grades of them.
The Superstat is the one you want, as I remember they had cheap ones and good ones.
The Superstat was the good one.

 

[BLKTACO]

I'd be concerned about it throwing the computer a curve ball.
I've had good luck with the Stant thermostats, think they still make a few different grades of them.
The Superstat is the one you want, as I remember they had cheap ones and good ones.
The Superstat was the good one.

Well you’re not wrong. This is the “cheap” one. It seems that Stant makes a SS that would fit but I can only find it on their website. I called around to auto parts stores none had the number in their system. You can barley pull it up in google. It gets you one result with Oreilly. They don’t have any.

The thermostat I have is sold by URD. Under 170 degree performance thermostat. URD manufactured high quality super charger systems for Toyota trucks. So while it may be cheap it’s hard to believe URD would sell a “cheap” thermostat.

As for the ECU, according to the FSM the normal operating temperature for the 5VZ-FE is between 175-205 so I should be right in the middle.

EDIT: if it’s worth mentioning the one I have was made in USA. Not made in China. So it has that going for it.

 

[MVP]

Well you’re not wrong. This is the “cheap” one. It seems that Stant makes a SS that would fit but I can only find it on their website. I called around to auto parts stores none had the number in their system. You can barley pull it up in google. It gets you one result with Oreilly. They don’t have any.

The thermostat I have is sold by URD. Under 170 degree performance thermostat. URD manufactured high quality super charger systems for Toyota trucks. So while it may be cheap it’s hard to believe URD would sell a “cheap” thermostat.

As for the ECU, according to the FSM the normal operating temperature for the 5VZ-FE is between 175-205 so I should be right in the middle.

EDIT: if it’s worth mentioning the one I have was made in USA. Not made in China. So it has that going for it.

Okay man, how's it working out? I'm fixing to order the same URD thermostat. Want your opinion on your experience with it.

 

[BLKTACO]

Okay man, how's it working out? I'm fixing to order the same URD thermostat. Want your opinion on your experience with it.

I did not get mine from URD but I am pretty sure URDs is also a Stant.

The new stat did bring temperatures down by about 10 degrees under normal driving. I was usually around 200 degrees before getting up to 205 stop and go. Now Im around 190 when on the highway. On really hot days about 194-196 and sometimes 200 idling at lights. On cooler days I've seen it drop to about 187 periodically. It hasn't been below 85 ambient since I put it in so ill see if it gets any cooler.

Many people have reported seeing temps of 180 with the URD stat. I haven't had that experience at all even with a brand new condenser, and OEM radiator. So I've been wondering if I was given a 180 stat in a 170 box. Parts stores mix things up like that often. And the Stant did not have a part number on it. Just said "Made in USA"

Here's why I think i may have gotten the wrong stat.

There are threads on people reporting temps drop 10 degrees just by rotating the OEM stat jiggle valve to 6:00. My OEM 180 was at 12:00 when i took it out. I made sure the "relief valve" on the stant was at 6:00 when I installed it. So in theory I guess I could have gotten a 180 and the only reason I saw temps go down is because the jiggle/relief valve is downward.

However I've been told many times that you cant get any cooling out of a thermostat, you need a better radiator. There is a much better Aluminum one out there people on TW are installing. But then that would mean everyone on CustomTacos seeing lower temps using 160 and 170 degree thermostats were lying or terribly mistaken.

I don't know dude. Install one and post your experience. Id like to know myself if someone else gets better results.

Sorry I couldn't be more help. Its just everything I know and my experience with it.

 

[MVP]

I did not get mine from URD but I am pretty sure URDs is also a Stant.

I don't know dude. Install one and post your experience. Id like to know myself if someone else gets better results.

Sorry I couldn't be more help. Its just everything I know and my experience with it.

Thanks for the additional info.

I'm ordering the URD and doing a bunch of work on the rig in about a month. Part collecting for now, then adding the supercharger, CS-144 alternator, and ARB bumper during the holidays since it is still over 100 degrees here regularly.

 

[4Runner fun]

thermostat

It’s 10 degrees cooler. One step down. It’s to help make the S/C more efficient.

ok, I've been following along not commenting, But my opinion on a lower Thermostat is not really a fix.
I drove and towed with a 454Chevy dually with a Whipple for over 100K as my primary tow/desert ride.


The kit came with a lower Thermostat, My first thought was great cooler is better. WRONG!!!!!
the second any supercharged motor goes on to boost it creates heat, the thermostat does not control that, the radiator and fuel system does, along with engine management.

As temps rise, timing is pulled out of the motor, and fuel is richened. And the fan clutch tries to draw air, the thermostat has nothing to do with any of that.

unless your cooling system is VERY efficient.

off boost the thermostat will keep the motor at operating temps, so if you over build your cooling system it will maintain a minimum operating temp. but as far as keeping temps down on boost?? no way.
a cooler plug and good engine management will work with an optimal cooling system.
Champion build a 3 row aluminum radiator that I went to, it is above the frame rails on a 3rd gen, and will cool in the worst off road conditions, and I'm sure would cool a supercharged motor quite well.

Again, just my .02:shrug: lol