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Mishimoto thermostat

Smitty

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#21
Blows my mind with all the failures with something as simple as as a thermostat. Jesus we’re not talking some high tech piece of equipment. It’s a friggin’ spring!
 


white1

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#22
Blows my mind with all the failures with something as simple as as a thermostat. Jesus we’re not talking some high tech piece of equipment. It’s a friggin’ spring!

Agreed!!!!!!!
 


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#23
Mine threw a code without a tune for the fans. After the tune I never saw a code in 5 years.
 


vortecd

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#24
Pretty sad we have to worry about this failing. I have the stock thermostat and a big bag ( @Speedy! idea) for catching coolant in the car just incase. I have swapped these out a few times and you can catch most of it with a bag and pour it back in to the reservoir

20220516_163721.jpg
 


16GoManGoHC2

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#25
Pretty sad we have to worry about this failing. I have the stock thermostat and a big bag ( @Speedy! idea) for catching coolant in the car just incase. I have swapped these out a few times and you can catch most of it with a bag and pour it back in to the reservoir

View attachment 70864
Better put a 13 mm wrench in that bag too to undo the Tstat housing. I had to do it along side the road myself one time, Thank God and Advance Auto was only right down the street and I got a thermostat from them.
 


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#26
it is very complicated. the spring has to work and the gasket needs not to be pinched.
 


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#27
Thankfully I've never had an issue.
 


vortecd

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#28
Better put a 13 mm wrench in that bag too to undo the Tstat housing. I had to do it along side the road myself one time, Thank God and Advance Auto was only right down the street and I got a thermostat from them.
I already keep a bag of tools with me, have done that for years:)
 


jonx96

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#29
I had one fail at bowling Greene. Luckily I travel with tools. Bad news. I won the race but didn’t get to win the war. It was an HHP branded one. I have since see them say they don’t recommend their tstat for a hellcat.
 


Hickster

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#30
like i mentioned, the k n works differently in the gms than the hell cat.
 


vortecd

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Something interesting. So Josh Schwartz was the number 1 qualifier at the NMCA hemi shootout in St. Louis this past weekend. I noticed he wasn't in the quick 8 Sunday and it was posted about his performance on facebook so I asked what happened Sunday

"we were concerned that it wouldn’t be safe for me, the car or the other racers after we had an overheat in competition on Saturday due to a cooling system parts failure so I gave up my #1 qualifying spot for Sunday in order to make sure the car is 110% ready in 4 weeks for MSHS"

thermostat?
 


Hickster

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#32
very well could beeze. cheap and sleazy,,, just like my past women. hopefully another coming soon.
 


OP
EricG

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Thread Starter #33

white1

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#34
Something interesting. So Josh Schwartz was the number 1 qualifier at the NMCA hemi shootout in St. Louis this past weekend. I noticed he wasn't in the quick 8 Sunday and it was posted about his performance on facebook so I asked what happened Sunday

"we were concerned that it wouldn’t be safe for me, the car or the other racers after we had an overheat in competition on Saturday due to a cooling system parts failure so I gave up my #1 qualifying spot for Sunday in order to make sure the car is 110% ready in 4 weeks for MSHS"

thermostat?

For tx2k we had to run straight water. After about the 5th time of flushing trying to get all the coolant out I left the thermostat out to make the process easier. I'm seriously considering leaving it out when the new engine goes in.

I learned (by accident) these vehicles (all hemis Ive experimented with) will run at 185 or higher. With a 160 thermostat, it will run 185. With a 180 thermostat it will run 185. With no thermostat it will run 185.

When the one in my scat pack failed a couple of years back, I couldn't find one local so I just put the gasket back and ran without and ordered a thermostat. My temps stayed the same as they had with the 180, and heater performance in the winter seemed unaffected (I do live in south Louisiana so we don't get cold cold, but do have a few mornings in the upper 20's to lower 30's)

I understand the point of a thermostat, however if your temps are similar with or without, I'm not sure I see any harm running without
 


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EricG

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Thread Starter #35
The one that opened and closed most consistently around 180, purchased from 3 different stores as 3 different brand boxes but all motorads inside each View attachment 70656 View attachment 70657 View attachment 70658 box, all around 10$ each. I always test T stats before use, I bring them up to temp very slow and watch which one cracks first, get fully open first, and closes correctly then make a pick and return the others for refund lol.
Ah yes, the good ol' Motorad 4128! I have been using them since 2007, bet I've done at least 20 thermostat swaps. So I've never had a problem with them, but I feel like I read about a lot of failures on them over the past 2 years, saw some mentions of the Mishimoto so I thought I would give it a try. I think it was almost $50 too.

So the Motorad/Jet/whatever seems to hit 187-188, then settles to 185 after airflow and open loop mixing...the Mishimoto seems to open at around 177-178, mix for a bit, then adjust up to 185. I only threw a code one time over the years with the Motorad/Jet, did right away with the Mishimoto. Will probably swap back. I drive to work early in the morning and my car just gets up to operating temp by the time I get to work so I think I really test the code threshold.

Interesting/funny, one time with my Scat Pack around 2018 I went out to lunch with my boss and I was driving, it was summertime hot, had a Jet 180 in it. On the way back we were ripping around, A/C on, all the sudden I see my coolant temp gauge spike to 270! Limped the car back to work, called Dodge Cares, got it towed to the dealer and they replaced the water pump and tstat under warranty. Car ran fine after. Anyway, i always wondered if my tstat broke in the closed position then. Guess I'll never know...
 


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jonx96

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#36
I already keep a bag of tools with me, have done that for years:)
Well you used to drive mustangs so this makes sense :ROFLMAO:
 


vortecd

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#37
Well you used to drive mustangs so this makes sense :ROFLMAO:
I found over the years when modifying cars there can be issues. I would keep spare parts (old take offs) in my car like a blower belt or idler pulley just in case. The tools were needed by other people more then me when hanging out at the lot on the weekends:)
 


Smitty

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#38
I found over the years when modifying cars there can be issues. I would keep spare parts (old take offs) in my car like a blower belt or idler pulley just in case. The tools were needed by other people more then me when hanging out at the lot on the weekends:)
Even on my normal vehicles I keep some basic tools on hand. Amazing how handy a screwdriver or a pair of pliers can be. And on longer trips it seems I have half the tool box in the car. Oh and don’t forget the duct tape. 🤔
 


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#39
my last name is duck,,, and i invented the duckster tape. comes in many flavors now,,, like sour doogh,, boy.
 


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EricG

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Thread Starter #40
Small update here, swapped back to the Jet 180/Motorad 4128 unit and my code P0128 has gone away after a few days.

This one climbs to 188-190, then opens and settles at 185 or so(when air is moving through the car of course).
 




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