What degree thermostat for '89 Southwind w/454

[Senior Chief]

Just pulled the (stuck shut) thermostat out of the 454 in the MH. Its a 195 degree; is that stock?

[Aguyfromcalg]

195 degree thermostat is hot. That is what I would use for a cold winter. 160 degree thermostat may be more suitable for summer driving

[JimElliott]

Quote:

Originally Posted by Senior Chief Just pulled the (stuck shut) thermostat out of the 454 in the MH. Its a 195 degree; is that stock?

Yes, 195* is stock and in your region it might be best to replace it with a GOOD 195* stat...

Down here in the low desert I use an 180* "Robert Shaw stat" along with a mixture of 30% anti freeze and 70% distilled water, While climbing hills the temps will nudge up to 190*......

Jim

[Sammie]

Quote:

Originally Posted by JimElliott Yes, 195* is stock and in your region it might be best to replace it with a GOOD 195* stat... Down here in the low desert I use an 180* "Robert Shaw stat" along with a mixture of 30% anti freeze and 70% distilled water, While climbing hills the temps will nudge up to 190*...... Jim

Ditto, What Jim says! I used to own a 1990 Pace Arrow with the 454 Chevy and thats what I ran for a thermostat.

Sammie

[bachler]

We had 4 454s;; The EPA. Said 190 Deg; I said. In the cylinder That Runs near 3000 Degrees when it fires; Exhust manifolds That get so hot they brake and snap Bolts; yet some dumbo in the government tells us to run the engine. ( way to hot) and we beleive them.. Heres the bottom line. When oil gets over 230 deg it is basicly a vaper mist; And has near no couchioning affect Hens. The r, rear cylinder will scour the wall and breake the shirt out of the piston. Now with the computer on the engine the throttle body. 1990 And newer They don't like the Lower thermastet .. I have allways run a 165 deg. thermastet and loged over 100000. thousand miles on the engines. Tell the 1994 TB> I run it with the 190 ther. And vollo . at 53000 miles it took the RR< piston out ,, Now Try to tell me they run better with a 190... NO They run worse and not as long.. OH we ran in ARZ> ALaska . And even NORTH DAKOTA;;

[bachler]

I almost forgot I raced/built race engines; Ok in the drag It would have to run at most 10 seconds;; And at the sprint car; Maybe 100 miles. So I get a bit worried when it is brought up about race engines;; There Is NO compareso . Other then they are both Combustion engines;;

[ccook129]

The all too commonly used 160 degree thermostat is way too low to be considered for performance or engine longevity. Engine wear increased by double at 160, than at 185 degrees. So then, why do the 160's exist in the first place? The 160's were commonly used in older, open loop cooling systems where only 6 pound radiator caps were used, and low 212 degree boiling points were experienced. In contrast, modern cooling systems can see upwards of 260 degrees in coolant temperature with radiator pressures exceeding 45 pounds. Many early hot rodders found the 160's to be better performing than the 190's, however, the in between "180" appears to satisfy both ends of the spectrum. The correct water temperature is required for the cylinders to achieve a minimum specific temperature in order to allow a fully homogenized Air/Fuel mixture to combust efficiently. Guess what the minimum number is… right! 180 degrees. Even so, you might see some still recommending the lower 160's, for no other reason than to possibly get that last drop of horsepower out, at the high price of dramatically reducing the life of the engine and it's internal components.

For example an NHRA Pro Stock engine makes over 1,400 HP and uses a 0W-5 weight engine oil. A NASCAR Nextel Cup Engine only makes 850 hp but uses a 5W-20 weight oil. How can a more powerful drag motor use a lighter weight oil? The NHRA Pro Stock motor runs at a cool 100 degrees F. A NASCAR Nextel Cup engine runs around 220 degrees F. Our Joe Gibbs Driven XP0 racing oil is 11.5 Centistokes at 100 degrees F, and the XP0 oil is popular with the NHRA drag racers. Joe Gibbs Racing uses the XP1 in our un-restricted NASCAR Nextel Cup engines, and the XP1 is 9.5 Centistokes at 212 degrees F. As you can see, the operating viscosity of the 5W-20 XP1 oil is lighter than the operating viscosity of the 0W-5 XP0 oil due to the difference in operating temperature.
http://www.joegibbsracingoil.com/tra...er/082106.html

[ccook129]

YouTube - Testing an F1 Engine

This is Hot

[Senior Chief]

Thanks, everyone!

[leadman]

I just put a 195' t-stat back in my '88 Itasca 454. The 180' t-stat would start letting coolant into the radiator at 160', then the fan clutch would engage at 170'. Not good for mileage.
The tech at the fan clutch manufacturer said to install a 195' t-stat without the bleed hole so the fan clutch would engage at the proper temps.
I need to test the operation on the road but the fan clutch was working properly in the driveway today after the 195' t-stat was installed.

[Midniteoyl]

ccook is correct.. the hotter the better in most cases for better efficiency... modern stats are usually at 200F (95c)

[melvonnar]

Quote:

Originally Posted by JimElliott Yes, 195* is stock and in your region it might be best to replace it with a GOOD 195* stat... Down here in the low desert I use an 180* "Robert Shaw stat" along with a mixture of 30% anti freeze and 70% distilled water, While climbing hills the temps will nudge up to 190*...... Jim

Agreed' only one thing: make sure the fan cluch works as it should. I had a 1988 southwind with a 454 and the fan cluch was the only problem.

[4Knights]

Quote:

Originally Posted by melvonnar Agreed' only one thing: make sure the fan cluch works as it should. I had a 1988 southwind with a 454 and the fan cluch was the only problem.

What was your fix for the fan clutch?

[melvonnar]

Quote:

Originally Posted by 4Knights What was your fix for the fan clutch?

I replaced it with no less than 3 aftermarket clutches, don't go that route, none of them worked properly. I bit the bullet and bought a factory fan clutch, at that time $185.00 (ouch) but it did the job. If you here your fan clutch comming on (it will make a roaring noise) when pulling a long hill, your most likley ok.