Thread: 180 thermostat really needed?

So I have read about every thermostat thread on here and I see mixed results. Some say and the guide recommends a 180 while others state the stock 195 is fine. Regardless of temperature tuning for it is important which I am doing.

I am a top swap, VS cam, headers, and soon to be E85. I have a dyno tune coming up in several weeks to tune and find the best pulley size. My tuner recommends a 180 but is it necessary? Will it allow me more timing, smaller pulley, or less risk of knock? I run a 195 because I like the heat output in winter. My experiences with a 180 in the past with other vehicles the heater difference is noticeable. I don't like a crappy heater in the winter on a dd with two young kids.

(I am also doing a fuel pump rewire, 60 Injectors, and AEM pump)

e85 no care about temps but fuel temps

engine bearing clearances are set for an operating temp, GM did engineer em

as long as its drilled with a 1/16th hole at the high point (or I just clip off the "dingleberry" that some come with) to let any steam escape/make sure the T stat pellet is covered in coolant so that it opens properly

high pressure from a WP at high rpm can keep it from opening as fast but you should already be at operating temp for 20 minutes before you beat on it

cold oil/atf sucks. its why the new dex6 is thinner when cold, our trans filters don't like cold fluid, esp with 30wt hydrostatic oil at 50/50

No need for one.

Originally Posted by Fivefingerdeathpunch

No need for one.

Which you always post but can never back up with anything.

GTFO with this crap.

The rated temp on the TStat's are always 10-15* less than the operating temp.

Hence why the stock 195's run around 210-215, 180's around 190~, and 160's around 175-180. Tested all three. I ran 160's all day long with no issues. Most people run 180's. It's not a big deal. However I'll never run a stock temp T-Stat because: **** heat.

Maybe your cars run warmer or they just suck and hate you.

I never had one single issue running a 195, never had temps at a consistant temp above 205º ever.

Prove to me that running a 180 is better and I want detailed facts with proven numbers about why it benefits the car or you can shut the **** up. Also not everyone lives in the hottest places so the need for a 180 isn't there. Middle of the desert or something maybe to try and lower temps but even that won't work well when it's extremely hot out. Nobody is going to want to beat on there car when ambient temps are through the roof either, everything is down on power.

Tell me why anyone that runs even more powerful engines in different vehicle classes don't bother running a cooler thermostat. This is rarely a topic for discussion on the performance truck boards I'm on. Guys are running 700-800+ horsepower with stock water pumps and stock thermostats because that **** doesn't matter. Keep the air charge cool and fueling there and it won't give a damn.

Originally Posted by blueguy

The rated temp on the TStat's are always 10-15* less than the operating temp.

This is bull**** too. I could go out and provide you with log after log of my truck with a 195º thermostat running between 192-199º any day while driving. Wouldn't matter if I drove it nicely or if I was hammering on it for miles.

If what you said was true, the thremostat would be open 100% of the time and never close because the designed open temp is 195º.

There is a "slight" difference between a truck's cooling system, and the W bodies.

I guarantee if you pulled the radiator, water pump and thermostat from both and laid it all out, compared them side to side, you'd see the difference very clearly.

Not saying that you are wrong, but stock W body radiators suck. Their water pumps are tiny and a poor design for moving fluid through the block. And I'm pretty sure the space available for fluid to move through when the thermostat opens is pitifully small on a W body.

If the system is full of old dexcool sludge, or has a decent film of it left in the block, it's not going to cool the car efficiently at all. Plus the fact that 3800s can get stupid hot, you've confirmed that yourself in the thread about the Amsoil testing facility, means that most 3800s will most likely see up to 5 degrees higher temps than other cars/trucks/whatever with similar thermostat temperatures.

If we are comparing the 3800 to a 5.3 V8, then yeah the smaller V6 parts are going to look small. The V8 has 100 more cubic inches and a bigger engine to cool so the parts have to be larger. Still doesn't change the fact that the 195º thermostat is just fine for either application.

The W-body radiator is rather larger when you look at it, it covers pretty much the entire area between the head lights. Problems come from lack of airflow with damaged air ducts/dams and dirt build in in the fins of the radiator. You'd be surpised how much better they cool with nothing blocking the airflow into the fins. The water pump design isn't that bad, pretty standard among GM cars and for the size of the engine it does the job.

I didn't mention coolant temps in the amsoil thread, I was talking about oil temps and the lack of oil flow these engines have. No oil cooler

Coolant temps are the last thing I'd be concerned about for power and the performance of these engines.

I run a 195, and after changing the fan settings I'll see maybe 200-205, but there's still a little sludge in my cooling system and my radiator probably needs some love.

Before that, my fans NEVER kicked on, and I think the stock setting is something like 230.

No, you didn't mention coolant temps, but wouldn't oil temps be a good way of describing how hot the engine itself gets? Coolant is designed to keep the engine from overheating, but these engines run at higher temperatures than others in the first place. An oil cooler would be nice to implement, but impractical and unnecessary.

I do believe cooler temps would help with detonation, but not to a large enough degree to make it a worthwhile performance mod. Engine longevity, maybe...but that's a different story.

If I had unlimited money and tuner and could run some experiments on a dyno..... Sigh. I am still leaning towards running the stock 195 thermostat.

i run a 195 with the fans set to 185. runs around 200 give or take some.