ok if 195 are mainly for emissions, and 180 make the engine run cooler, and more efficiently why didnt they just instal them form the factory? and installing one will that just make it longer for the engine to warm up?

 

the manufacturers have to meet certain requirements for emissions whenthey roll out a new car. after you buy it ou can do whatever you want to it because its out of the manufacturers hands so they dont really care.

 

It does take a little longer for the engine to warm up. You can purchase a cheap one for $3 at any local auto parts store or you can buy a nice one from hypertech for about $10. Remember, you get what you pay for.

 

I just put a 180 in mine and i dont really notice a HP diffrence but i do notice the lower temp, little longer to warm up and better oil pressure when the engine is warm. All in all it was well worth it.

 

I have a 180 in mine and I like it. it runs alot cooler now.

 

i bought mine from auto zone for $5 no problems, runs considerably cooler

 

Kenne Bell company put out a 'Technical Tips' document back in year 2000 saying that changing from a 195 to a 180 thermostat on a model year 1998 Magnum 5.9V8 showed no measureable change in either torque or horsepower at any rpm on their in-house rear wheel dyno.

This has been my experience too,
and i have run:
no thermostat, 180, 195 and 205 thermostats
on a model year 1995 Magnum 5.9V8.
The 180 thermostat did not reducing pinging at wide open throttle and 95 F outside air temperatures on 87 octane gasoline....but no thermostat did reduce pinging (I am not advocating no thermstat)

The 205 thermostat slightly improved MPG and the 180 slightly hurt MPG.

Using Evans NPG coolant I have also operated the engine at coolant temperatures of 280-300 degrees F and it runs smoother the hotter it gets.

 

FYI, running a 180 thermostat will not cause the motor to take longer to warm up. It will simply open the thermostat at 180 instead of the OEM tstat (195).

 

since i have the 4.7 engine, im guessing what hankL said doesnt apply?

 

Because the 4.7 has a plastic intake manifold designed to shield the intake air from picking up heat...it is even less likely that a cooler thermostat would improve performance compared to the 5.2/5.9V8s that still have aluminum intake manifolds.

There is a lot of myth and non-sense still circulating on the internet about thermostats, engines and performance.

What you want is cooler intake air and hotter cylinder walls.
The cooler air has more oxygen and can allow more fuel to be added, plus there is less tendency to detonate.

But the hotter cylinder walls have the dual effect of robbing less heat from the combustion gases which gives them more pressure...AND...the heated cylinder walls make the lubricating oil thiner and less viscous and so there is less friction from the piston rings.

This stuff has been known for more than 60 years.

Want a second opinion from a famous non-engineering degree 'good ol'boy' NASCAR engine builder?

Read Smokey Yunick's book 'Power Secrets' where he tells about his experiments that found that as long as the intake manifold air is well insulated and the fuel octane level is high...the horsepower keeps going up as the coolant temperature goes up.