For archival/informationl purposes, here are the part numbers for the 6.1 Hemi Stant Super Stat thermostats in cooler ranges from NAPA:

180 degree
NAPA #532080
Stant #45478

192-195 degree
NAPA #532090
Stant #???

Stant 14429 balanced sleeve 190-195.........originally for the Ram diesel....went right in.

What is so special about the Stant vs the Napa model?

What is so special about the Stant vs the Napa model?
Same thing with different numbers. No difference.

The Stant had a larger opening and was a balanced sleeve style thermostat. The design is suppossed to be superior...........but you need to do your own research of balanced sleeve vs poppet style and make your decision.

The Stant had a larger opening and was a balanced sleeve style thermostat. The design is suppossed to be superior...........but you need to do your own research of balanced sleeve vs poppet style and make your decision.

Agreed:

Having purchased both styles of thermostats, the Stant does have a larger opening. Compared to the stock thermostat (which has a very large opening), I would be leary about using any cooler thermostat with a smaller opening (mid-summer heat, towing a boat, or any other continuous load issue). Just one person's thoughts on the matter. As for a one day observations associated with the Stant 195 degree thermostat, it indeed runs 8-10 degrees cooler based on the console display, with the oil temp also running correspondingly lower. Mileage will have to be determined over time, but over 24 hrs, no change. I don't want to speculate on performance without data to back it up, but I can't imagine that it's worse than stock! As for oil pressure PSI, I might have seen a minimial increase using the stock Mobil 1 0-40W before and after the thermostat change.

Noted the same.........there is about a 7-10 hp difference noted on the dyno when it cooled to 190.

Thanks for the info. I think I will get the 192-195 degree stant model. Is the stant also available from NAPA?

Thanks for the info. I think I will get the 192-195 degree stant model. Is the stant also available from NAPA?

Got mine at Pep Boys.

Noted the same.........there is about a 7-10 hp difference noted on the dyno when it cooled to 190.

The butt dyno thinks that the low RPM response is improved with the lower temps.

Agreed:

Having purchased both styles of thermostats, the Stant does have a larger opening. Compared to the stock thermostat (which has a very large opening), I would be leary about using any cooler thermostat with a smaller opening (mid-summer heat, towing a boat, or any other continuous load issue). Just one person's thoughts on the matter. As for a one day observations associated with the Stant 195 degree thermostat, it indeed runs 8-10 degrees cooler based on the console display, with the oil temp also running correspondingly lower. Mileage will have to be determined over time, but over 24 hrs, no change. I don't want to speculate on performance without data to back it up, but I can't imagine that it's worse than stock! As for oil pressure PSI, I might have seen a minimial increase using the stock Mobil 1 0-40W before and after the thermostat change.

Try Mobil1 15/50 and watch the difference......

192-195 degree
NAPA #532090
Stant #???
Just as a data point, I installed the above unit this morning. With the stocker I was running 215 on the dash guage and with this I am running half way between 200 and 215 on the guage so assuming the guage is linear It brought the temps down about 7.5-8 degrees F. Not as big of a difference as I anticipated. I wonder how accurate the dash guage it.

Just as a data point, I installed the above unit this morning. With the stocker I was running 215 on the dash guage and with this I am running half way between 200 and 215 on the guage so assuming the guage is linear It brought the temps down about 7.5-8 degrees F. Not as big of a difference as I anticipated. I wonder how accurate the dash guage it.

Mine runs at or, just a hair above the line left of or below the 215 mark......sometimes in stop and go on the freeway it will see the 215 mark. I just tested it on the dyno and it makes a difference........combined with two or three mods you may see a performance gain. I'll know this week and post it.

Just as a data point, I installed the above unit this morning. With the stocker I was running 215 on the dash guage and with this I am running half way between 200 and 215 on the guage so assuming the guage is linear It brought the temps down about 7.5-8 degrees F. Not as big of a difference as I anticipated. I wonder how accurate the dash guage it.

With the Stant 195 degree, I'm running right at 200 degrees when cruising. Stock, I ran at 215 degrees when cruising. My exhaust tips are less black, and over 4 days with the same driving habits, my mileage is up 0.5 mpg.

How difficult is it to replace the thermostat yourself?

Try Mobil1 15/50 and watch the difference......

does that oil carry the recommended classes for this engine?
________
BUY DIGITAL SCALE (http://www.vaporshop.com/scales)

How difficult is it to replace the thermostat yourself?

Very easy. Remove/put aside the air intake rubber tube, put a clamp on the upper radiator hose to limit antifreeze loss, remove the two bolts attaching the thermostat housing to the water pump, remove the housing, remove the thermostat, put the rubber o-ring on the new thermostat (located on the existing thermostat), then re-install in reverse. Start engine, with cap off radiator add 50/50 antifreeze to radiator until full once the engine is up to temperature (so that the thermostat is open and purges the air out). Obviously, do at own risk.

With the Stant 195 degree, I'm running right at 200 degrees when cruising. Stock, I ran at 215 degrees when cruising. My exhaust tips are less black, and over 4 days with the same driving habits, my mileage is up 0.5 mpg.


My is stock and today with temps around 95 going 75-80 Mph mine got up to 237. Is that normal? Thanks for the instructions on switching the thermostat. It seems like it's for someone that knows what their doing.

What is the problem with using a 180 degree vs the 195?


What difference will the different oil types make?

Just trying to get some info.

Only have 200 miles on mine, wanna do it right from the start
thanks

This is what my Tstat looks like. Wrong Napa # for by-pass stat.

http://i7.photobucket.com/albums/y292/kpie/P1010330.jpg

http://i7.photobucket.com/albums/y292/kpie/P1010329.jpg

http://i7.photobucket.com/albums/y292/kpie/P1010328.jpg

Also, the size for water flow is WAY off.

[QUOTE=hemicon]This is what my Tstat looks like. Wrong Napa # for by-pass stat.QUOTE]

Did you heat the two units up to operating temperature to see what the flow passage size is when open? When I looked at the two I did not think you could really tell by looking at them cold.

If you look at the black part of the stocker picture, compared to the napa dark color. stock hole is 1-5/8 napa is less then 1". Thats pretty big differance.
180* starts to open @ 184*
stocker starts @ 205* and is opened all the way @218*

Also the by-pass is not moved by temp. It works with water pump pressure.
I dont know the water flow on the hemi's. But on the Chevys, if you do not run a by-pass were a by-pass was you get hot spots on one of the heads.

A better fit is the napa# 154 It is a 1990 mazda mpv with the 3.0L V-6
this is still not a perfect fit. It's a 64mm not a 63mm. I had to do a little file'n and had to cut 2 coils off the by-pass spring to match the stock hemi spring pressure. It's 180* stat. and has the big flow opening.

http://i7.photobucket.com/albums/y292/kpie/P1010326.jpg

If you look at the black part of the stocker picture, compared to the napa dark color. stock hole is 1-5/8 napa is less then 1". Thats pretty big differance.
180* starts to open @ 184*
stocker starts @ 205* and is opened all the way @218*

Also the by-pass is not moved by temp. It works with water pump pressure.
I dont know the water flow on the hemi's. But on the Chevys, if you do not run a by-pass were a by-pass was you get hot spots on one of the heads.

A better fit is the napa# 154 It is a 1990 mazda mpv with the 3.0L V-6
this is still not a perfect fit. It's a 64mm not a 63mm. I had to do a little file'n and had to cut 2 coils off the by-pass spring to match the stock hemi spring pressure. It's 180* stat. and has the big flow opening.

http://i7.photobucket.com/albums/y292/kpie/P1010326.jpg

The Stant 14429 has a larger opening than the Napa TStat, but I can't be sure that it has a pressure bypass valve.

I dont know what the 14429 is?

The 14168 is the napa 154 or the mazda stat. Is the most like a stocker.

I just would not recommend these #'s

180 degree
NAPA #532080
Stant #45478

192-195 degree
NAPA #532090
Stant #???

I'm not knocking anyone, just showing what I've found:)

Is swapping your tsat something you want to ask your dealer to do? would that void the warranty?

Well, my 203* (stock) stat is back in:(

The first tank of gas I did not notice mpg loss. By the 2nd and 3rd tank mpg's were bad.

I have a 5.7 ram not a 6.1 You might be ok or not, just beware. If I bought a chip to tell the ecm that 180* was full op temp it would(should)work.

Apologies for asking but what's the advantage of the stant or napa thermostat over the stock one. I would guess more hp?!?! but why? and how does the new thermostat affect mileage and how will the water temp be affected on hot days/heavy loads?

Thanks for the insight.

is the stock thermostat setting programmed into the comp? i.e. ifi put in a 180 stat will the ecu know the temp as 180or will it see it as 203?Just wonderingbefore i throw one in.thanks

Why cooler t-stat???

Cooler motor temp= less ping (knock)
no pinging= more timing
more ing. timing= more power:D

stock=203*
napa/who ever = 180 or 190*

Better is not part of it, just what temp it opens.