What "degree" Thermostat

Posted By: YO7_A66

Re: What "degree" Thermostat - 06/28/10 07:35 PM

I have a 195 and the gage in my Challenger shows straight up at this temp.

Posted By: rm23j8g

Re: What "degree" Thermostat - 06/28/10 07:55 PM

Quote:

I have a 195 and the gage in my Challenger shows straight up at this temp.

IIRC, the 195 thermostats began being used in most Chrysler engines in 1970.
I have 195s in my '70 cars as well and the gauges also read almost dead center.

Posted By: stumpy

Re: What "degree" Thermostat - 06/28/10 08:08 PM

terzmo, before you post anymore inaccurate info on this subject I respectfully suggest you do some reasearch. Engines have been running 195 stats from the factory for a long time and 195 is not the high end of the heat range or the gauge for older engines. 215-220 is too hot not 195. BTW nice edit on the earlier post.

Posted By: pwr440

Re: What "degree" Thermostat - 06/28/10 09:59 PM

Whatever one you get you might want to check it on the stove with hot water and a thermometer. 2 weeks ago I bought a heavy duty 195 from NAPA and after my car boiled over I checked it. Water on the stove was boling away @ 2o3 degrees and the stat didn't open. I tested my old 160 and it opened @ 180.

britt

Posted By: joedust451

Re: What "degree" Thermostat - 06/28/10 10:12 PM

Quote:

terzmo, before you post anymore inaccurate info on this subject I respectfully suggest you do some reasearch. Engines have been running 195 stats from the factory for a long time and 195 is not the high end of the heat range or the gauge for older engines. 215-220 is too hot not 195. BTW nice edit on the earlier post.

When i ran the 180*, my temps stayed at 185* max, so this proved that its keeping the coolant in the rad. longer to keep a steadier temp, with the 160* it keeps creaping up to 190/195*, i'll admit, i'm not running a shroud, i'm sure that'll help, but it did stay at a steadier & lower temp with the 180*. Back in the day, i've pulled several factory stats out of mopars that were stamped 192*, so it goes to show, they ran them on the warm side.

Posted By: 474218

Re: What "degree" Thermostat - 06/28/10 11:34 PM

It took about two seconds for me to open my 1969 Plymouth Service Manual to page 7-1.

Which reads that a 190 degree thermostat is used on all models except those equipped with the 170 ci slant six which uses a 200 degree thermostat.

Posted By: 383man

383man - 06/28/10 11:59 PM

Most new modern engines run in the 200 to 220 range which is best for emissions but not performance. The manufactors did not build the cars for drag racing (most of them) they were built for low emissions and fuel milage and to be very efficent. But ask any drag racer what temp he likes his eng at when he leaves the starting line ?? I can tell you my 63 and all my cars that I have owned run the fastest running about 160 when I launch and then it is about 170 to 180 crossing the stripe but it can be hotter on real hot days. If the eng is to hot it wont fill the cylinders as much which can hurt performance. I prefer my eng to run about 180 on the street but I did not build it for fuel milage or emissions.

Ron

Posted By: joedust451

Re: 383man - 06/29/10 12:52 AM

Quote:

Most new modern engines run in the 200 to 220 range which is best for emissions but not performance. The manufactors did not build the cars for drag racing (most of them) they were built for low emissions and fuel milage and to be very efficent. But ask any drag racer what temp he likes his eng at when he leaves the starting line ?? I can tell you my 63 and all my cars that I have owned run the fastest running about 160 when I launch and then it is about 170 to 180 crossing the stripe but it can be hotter on real hot days. If the eng is to hot it wont fill the cylinders as much which can hurt performance. I prefer my eng to run about 180 on the street but I did not build it for fuel milage or emissions. Ron

Ron, if you really think about it, its not so much with having a cooler head/block/cylinder temp as it is having a cooler intake/fuel charge going in

, A 180* engine will have a "warmer" intake then an engine thats at 160*, so you then have a warmer intake charge, thus in a sence gives a slower ET & MPH, thats why guys would Ice down there intakes, then push them to the box, you then in a sence will show a cooler engine because the stat is in the intake, but the rest of the engine will still be on the warm side, the cooler intake charge is like racing in cooler air, it gives you the same affect, i personally never noticed a any real change from run too run "in COOL" air whether i was at 160-165* or 180*, now in the hot air, it might benifit cooling down the engine a bit, this will also cool down the intake charge, but iceing down is the best way in hotter air, of coarse thats getting harder to do now that they've been cracking down on that.

Posted By: Supercuda

Re: 383man - 06/29/10 12:58 AM

I run as hot a thermostat as I can get. 195 is usually it, but sometimes I can find a 205 degree one.

Define efficient? Getting the most out of the least is one way. Be it mileage or power. Modern engines make as much NET HP as the muscle car era engines made GROSS, yet double the mileage. You still want to argue that cold engines are better for efficiency or power?

Posted By: JonC

Re: 383man - 06/29/10 01:00 AM

Quote:

I run as hot a thermostat as I can get. 195 is usually it, but sometimes I can find a 205 degree one.

Define efficient? Getting the most out of the least is one way. Be it mileage or power. Modern engines make as much NET HP as the muscle car era engines made GROSS, yet double the mileage. You still want to argue that cold engines are better for efficiency or power?

Posted By: terzmo

Re: What "degree" Thermostat - 06/29/10 01:28 AM

Dearest Stump...before You whack someone,invest some time in reading comprehension as I stated earlier that 195 was approaching the high end of the normal operating range. Run yours hot...I'll run at 180

Posted By: SomeCarGuy

Re: What "degree" Thermostat - 06/29/10 01:54 AM

Quote:

It took about two seconds for me to open my 1969 Plymouth Service Manual to page 7-1.

Which reads that a 190 degree thermostat is used on all models except those equipped with the 170 ci slant six which uses a 200 degree thermostat.

It also says that a stuck thermostat causes a lean condition due to the cooler underhood temps.

Posted By: Darryls-Demon

Re: What "degree" Thermostat - 06/29/10 01:57 AM

I have never heard of an engine biulder making a power pull on a dyno at 190 degrees. If the dyno operator wants the motor to make more power he runs the motor cooler.

Posted By: d-150

Re: What "degree" Thermostat - 06/29/10 02:31 AM

i have seen a couple articles where 180 is optimal for performance

Posted By: stumpy

Re: What "degree" Thermostat - 06/29/10 03:02 AM

Quote:

Dearest Stump...before You whack someone,invest some time in reading comprehension as I stated earlier that 195 was approaching the high end of the normal operating range. Run yours hot...I'll run at 180

Yes after you edited the post.

Posted By: ahy

Re: What "degree" Thermostat - 06/29/10 03:06 AM

There was a poster - with real data - that showed the cylinder wear rate trade-off vs coolant temp. Cooler temps promote collection of fuel on the cylinder walls and reduce lubrication and engine life.

Dyno and drag race experience says cooler temps around 160 make more power.

A "sweet spot" in the trade-off was 180. Wear was reduced without much power loss. Plus in older MOPAR's keeping coolant temps a bit lower that current new car standards helps keep oil temp down, oil pressure up and detonation under control.

That's why I use a 180 stat.

Another benefit is consistancy. On a roll my cooling system can always maintain 180 so temps for tuning are consistant. If it creeps up to 190/195 with extended idling and AC on a hot day that's still OK. It cools right back down when I get moving.

Posted By: stumpy

Re: What "degree" Thermostat - 06/29/10 03:15 AM

Can you find this post? I'd like to see how he arrived at this conclusion. It would be interesting reading.

Posted By: 474218

Re: What "degree" Thermostat - 06/29/10 03:31 AM

Quote:

There was a poster - with real data - that showed the cylinder wear rate trade-off vs coolant temp. Cooler temps promote collection of fuel on the cylinder walls and reduce lubrication and engine life.

Dyno and drag race experience says cooler temps around 160 make more power.

A "sweet spot" in the trade-off was 180. Wear was reduced without much power loss. Plus in older MOPAR's keeping coolant temps a bit lower that current new car standards helps keep oil temp down, oil pressure up and detonation under control.

That's why I use a 180 stat.

Another benefit is consistancy. On a roll my cooling system can always maintain 180 so temps for tuning are consistant. If it creeps up to 190/195 with extended idling and AC on a hot day that's still OK. It cools right back down when I get moving.

I bought a new 1975 Dodge B100 van. From the the day I drove it off the lot the tempature gage never read in the normal range. The highest the neddle would get was just below normal. Since I lived in the desert in California I thought that was good. Will at about 12,000 miles it started using oil, lots, a quart every 300 to 500 miles. The dealer found the rings had never seated. The reason: the themostat and the exhaust heat riser were stuck open.

Heat is required.

Posted By: 383man

383man - 06/29/10 05:50 AM

Quote:

I run as hot a thermostat as I can get. 195 is usually it, but sometimes I can find a 205 degree one.

Define efficient? Getting the most out of the least is one way. Be it mileage or power. Modern engines make as much NET HP as the muscle car era engines made GROSS, yet double the mileage. You still want to argue that cold engines are better for efficiency or power?

Yes I do ! First I said 160 to 180 which is not cold just cooler then 195 or 200. Efficient ? Getting the most out of something or getting all it can out of the fuel that way you can get the most power out of every bit of fuel an eng uses. Thats what the late model modern engines are designed to do and they do that at 200 to 220 making sure there is enough heat to burn all the fuel for most power and less emissions. Now thats the Modern eng design and they can do it and not have spark knock or pinging issue's. Heck they can retard the timing in only one cyl if need be and not all of them unless it is needed. And they dont run full closed loop to about 180. I have no problem with modern design engines running at the 200 to 220 temps but not a 1960's or 1970's design eng. They want to get in the pinging mode real easy when they get over 180 as most are not quench engines and with higher comp ratio's of the muscle car engines to much heat will hurt. When the cyl fills in the new engines it is very well controlled with electronic multi port injection and good head chamber design. Most muscle car era eng cannot control cyl filling as well at all and usually put as much fuel as they can in it for power. But that leaves pockets of unburned fuel (hydrocarbons) which can start another flame front and cause detonation , pinging or spark knock. That is some of the reasons to much heat will hinder the muscle car era eng and once it creeps over 180 and up to 200 it can hurt. And I know all about cooling the intake charge to fill more cooler air into the cyl but if its to much heat in the cyl it can still effect the area of cyl filling from heat exspansion to a point. Plus the cooling systems on the older engines dont handle temps over 200 as well as modern cooling systems do. Now of course heat is power to a point in a cyl also but when all factors weigh in I can tell you all the cars I have raced run the best about 180 at the finish line. That is for the muscle car era engines as I do agree to a point about the temps of 200 to 220 are best for modern engines. In fact many of the later Mopar car engines of the 2000 year and up dont even turn the high speed fan on until 219. You can run your 205 thermostat all you want but I will stick with my 160 for my summer driving. Ron

Posted By: dulcich

Re: 383man - 06/29/10 07:08 AM

There is absolutely no debating that cooler water temps will make more power. If you want to cheat an extra ten HP out of an engine on the dyno, the way to do it is crank the temperature control down to 110 degrees. The cold run will ALWAYS make more power. Cold water and hot oil will always give the most power every time. Seen it hundreds of times in back to back tests.

-dulcich

Posted By: 360view

Re: What "degree" Thermostat - 06/29/10 11:23 AM

It was the aircraft engine manufacturer Continental that had the research showing that lower coolant temperatures made bore walls wear faster, but above 180 degrees the bore wall wear difference becomes pretty small.

Posted By: 360view

Re: 383man - 06/29/10 11:25 AM

This research from back in 1984
is interesting
in that it combines in one graph
both coolant temperature at the cylinder head
and compression ratio's
effect on both horsepower and fuel economy,
not in theory
but from dyno results.

My pencil marks showing degrees F are not clear, so
30 degrees C = 86 degrees F
50 C = 122 F
80 C= 176 F

Note that the ignition timing was optimized in the two cases
to "Light Knock"
at Wide Open Throttle for max power,
but 'Mean Best Torque' ignition timing
when at part throttle running where fuel economy was the goal.

The original SAE paper might be this one:
http://papers.sae.org/841294

For your daily driver
would you trade an
8% drop in max horsepower
for a
5% improvement in fuel economy?

The line for 122 degrees F might be doable in a reverse cooling set up where the cylinder head gets the cooler water and the block is at 176 degrees.

Attached picture 6059484-CompressionRatioVSCoolantTemperatures.jpg

Attached picture 6059484-CompressionRatioVSCoolantTemperatures.jpg

Posted By: DennisH

Re: 383man - 06/29/10 11:57 AM

Come on. 180 in the old school, 200 plus in the new stuff. Apples/oranges. Knuckleheads on ChallengerTalk are running 180's in the new Hemis. Not a good idea. 180 in my 440, and whatever the factory put in the new Hemi.

I have a neighbor that runs a 160 in his Studebaker. This thread is like the what kind of oil thread. Opinions are like a$$holes. Everyone has one.

Posted By: 474218

Re: 383man - 06/29/10 01:21 PM

Quote:

Come on. 180 in the old school, 200 plus in the new stuff. Apples/oranges. Knuckleheads on ChallengerTalk are running 180's in the new Hemis. Not a good idea. 180 in my 440, and whatever the factory put in the new Hemi.

I have a neighbor that runs a 160 in his Studebaker. This thread is like the what kind of oil thread. Opinions are like a$$holes. Everyone has one.

Why not run what the factory put in your 440?

Posted By: stumpy

Re: 383man - 06/29/10 03:10 PM

So you guys are saying that the tens of thousands of man hours and thousands of engine tests the factory engineers did are wrong and your few dyno test are better judges on what is best. It sure seems fuuny that all of the auto manufactures back then arrived at the 190+ temp for running their enegines.

Posted By: MoparforLife

Re: 383man - 06/29/10 05:11 PM

Quote:

So you guys are saying that the tens of thousands of man hours and thousands of engine tests the factory engineers did are wrong and your few dyno test are better judges on what is best. It sure seems fuuny that all of the auto manufactures back then arrived at the 190+ temp for running their enegines.

That is a compromise for daily driven everyday type vehicles, not HP competition motors where the optimal performance is desired. dulcich is referring to optimal performance will come with hot free flowing lubricant and engines warm enough to close up tolerance and a cool air/fuel inflow.

Posted By: terzmo

Re: What "degree" Thermostat - 06/29/10 05:57 PM

Quote:

terzmo, before you post anymore inaccurate info on this subject I respectfully suggest you do some reasearch. Engines have been running 195 stats from the factory for a long time and 195 is not the high end of the heat range or the gauge for older engines. 215-220 is too hot not 195. BTW nice edit on the earlier post.

post was edited a few minutes later to add a letter...not change verbage or point of the matter

Posted By: Supercuda

Re: What "degree" Thermostat - 06/29/10 11:07 PM

Modern engines use higher temps for a reason, it's more efficient, period.

Old school engines APPEAR to work better with colder temps simply because the intake isn't as hot. Which is NOT to say colder coolant is better, but it is to say colder intake temps are. Ever hear of icing down an intake?

Modern engines get colder intake temps by using a composite intake, not an aluminum one. Doesn't take a rocket scientist to see that having a composite 4bbl intake might be of benefit. But it might affect fuel suspension, which may be why they aren't made.

As for dynos, answer me this, who races a dyno? How many times have we seen an engine optimized on the dyno having a poor tune for the street?

As for the trade off between the temperature of the coolant and the affect on HP and MPG, you can have both. Years ago I had a heater hose tear a bit on my 86 Daytona. In Chicago, during a very cold winter day. I got 50 mpg on a 150 mile round trip. Hot block, ice cold intake. Been a believer in running warm coolant since.

Finally allow me to point out the no where does the OP say anything about maximum performance in regards to picking a thermostat rating.

Posted By: Crizila

Re: What "degree" Thermostat - 06/29/10 11:27 PM

I'm confused

Posted By: joedust451

Re: What "degree" Thermostat - 06/29/10 11:59 PM

Why is it that "simple" threads like this turn into a debate & get tons of experts, but when someone ask a "possible" brain stormer ALL the experts disperse

Posted By: DusterKrazy

Re: What "degree" Thermostat - 06/30/10 12:12 AM

Quote:

Why is it that "simple" threads like this turn into a debate & get tons of experts, but when someone ask a "possible" brain stormer ALL the experts disperse .

No kidding..
I asked what color a 1970 383 Magnum is and it turned into 3 pages of debated arguing and bs

Posted By: Von

Re: 383man - 06/30/10 12:28 AM

Quote:

Cold water and hot oil will always give the most power every time.:

Posted By: kenworth_goose

Re: What "degree" Thermostat - 06/30/10 12:37 AM

Quote:

Engines are more efficent and have less wear if run at 185-195. Any lower and your not getting all it's got and are wearing parts faster.

Are you nuts??? Any engine will wear far more at 185-195 than if you were running 160-170!! I can build tons more power at 160-170 than 185-195. Been there done that many times. Had many engines that had 195 stats and they ran good but when I'd drop to a 160 it's night and day difference. Why in the world is it the first thing to do to any car to make it proform better is to drop t-stat temp then??? Goes against everything you say.

Posted By: Supercuda

Re: What "degree" Thermostat - 06/30/10 01:29 AM

Quote:

Are you nuts??? Any engine will wear far more at 185-195 than if you were running 160-170!! I can build tons more power at 160-170 than 185-195. Been there done that many times. Had many engines that had 195 stats and they ran good but when I'd drop to a 160 it's night and day difference. Why in the world is it the first thing to do to any car to make it proform better is to drop t-stat temp then??? Goes against everything you say.

Go reread my last post and you'll understand what's affecting power. Been thousands of dollars spent my numerous manufacturers that show your wear comment to be absolutely wrong. Links have been posted, go read them.

Posted By: stumpy

Re: What "degree" Thermostat - 06/30/10 01:52 AM

Quote:

Quote:

Engines are more efficent and have less wear if run at 185-195. Any lower and your not getting all it's got and are wearing parts faster.

Are you nuts??? Any engine will wear far more at 185-195 than if you were running 160-170!! I can build tons more power at 160-170 than 185-195. Been there done that many times. Had many engines that had 195 stats and they ran good but when I'd drop to a 160 it's night and day difference. Why in the world is it the first thing to do to any car to make it proform better is to drop t-stat temp then??? Goes against everything you say.

I've been at this since 1965 and your statements are totally wrong. Dropping thermo temp is never the first thing you do. You stick to driving trucks and I'll stick to building engines like I have for the Last 45 years.

Posted By: SomeCarGuy

Re: What "degree" Thermostat - 06/30/10 02:14 AM

Quote:

Quote:

Engines are more efficent and have less wear if run at 185-195. Any lower and your not getting all it's got and are wearing parts faster.

Are you nuts??? Any engine will wear far more at 185-195 than if you were running 160-170!! I can build tons more power at 160-170 than 185-195. Been there done that many times. Had many engines that had 195 stats and they ran good but when I'd drop to a 160 it's night and day difference. Why in the world is it the first thing to do to any car to make it proform better is to drop t-stat temp then??? Goes against everything you say.

No. Engines do not wear more at 195 degrees. Not sure where you heard that.

You can make more power with cooler, denser air. No secret there.

Posted By: 451Mopar

Re: What "degree" Thermostat - 06/30/10 05:20 AM

I run the 180 degree stat in most of my cars, except the Charger. The charger is more of a strip car (500 cid and 12.4:1 compression) and i run 160 degree stat in it.

Posted By: Stroked65Belv

Re: What "degree" Thermostat - 07/01/10 06:32 PM

Milodon 180 Hi-Flow T-stat works awesome! Even has a small crease pressed into it for "burping purposes"! No need to drill a small hole. As the saying goes. You get what you pay for and this product works, even better when you use their Hi-flow Water pumps!