FooFighters92

iTrader: (2)

I've heard 160* are the worst thing in the world and the greatest.

I've heard 180* are the worst thing in the world and the greatest.

Nothing about 170*

So could someone give me some insight on which to go with for my '92 305 TBI. My car gets pretty hot sometimes and I'm trying to keep her cool, but I don't want to keep it in cold start mode and drink all my gas up.

abray1

170 is what Myron Cottrell says to use. He owns TPIS. John Lingenfelter used to like the 170. The cooler your motor is the more power it will make and the longer it will live. It has to be warm for the oil to work properly of course but 170 is the right stat.

Guest

160...iron motor holds heat, dont beat on it when cold. Once warm cast motor will start to heat soak anyway.

3rdgenmaro

iTrader: (9)

If your car runs hot, it is not the thermostat's fault (unless it is defective).
Odds are you need more airflow.

novaderrik

195.. but i'm weird..

hdis2002

iTrader: (1)

I'm running a 180 thermostat with a 195 fan control. Works very well for me. It's a 5.7 TPI. I rarely hit 200 degrees and I live near the coast in South Carolina. Friggin hot and humid.

Steve

TTOP350

iTrader: (8)

160 in all my "fun" cars.
you need a cooler t-stat aaaand a fan that comes on sooner. I'm not sure how the TBIs work.

The t-stat has nothing to do with cold start. its your exhaust gas temp and certain amount of engine run time.

FooFighters92

iTrader: (2)

I'm leaning towards the 160, and actually after doing a little online searching I can't even find a place that is currently in stock of 170 thermostats for our cars.

My car is always cool while I'm driving, but when I am at a red light or in park, my temps will rise, and fast. Sometimes the fan kicks on, and sometimes it doesn't.

red rock

iTrader: (2)

http://www.tpis.com/parts/view/217

FooFighters92

iTrader: (2)

My car is TBI, does that matter?

paul_huryk

Depends on a few things - TPI cars like cooler ones due to all the heat soak the aluminum intake tract can absorb.

TBI and carbed cars (most, but not all) typically like a higher temp one with a cold air intake to keep the air going into the engine coll and the fluids at the proper operating temps. In my 350, I run a 195 degree and have the fans kick on at 205 and 215 degrees. Car picked up power compared to running a 160 degree one and losing power to less than optimal thermodynamics on the cylinder head (aluminum L98). YMMV

3rdgenmaro

iTrader: (9)

How hot does it get? A different thermostat will not stop that from happening.

When you are moving, you are getting air across the radiator. You stop, then no more airflow. Depending on how hot your car is getting, you may need to upgrade your fans or change controllers to get them to come on earlier.

FooFighters92

iTrader: (2)

It gets to around 240 when the fan kicks on, and will lower the temp to around 220. When I am at a red light in stop and go traffic, or in a drive thru in park or something the car will get to 260 easily with no easing of temperature, it redlines and stays there.

built91Z28

I would get an IR thermometer and check the radiator temp at the inlet and see what it says. I have zero faith in the factory guages.

Your fan is coming on though right?

FooFighters92

iTrader: (2)

It comes on sometimes and other times it doesn't, otherwise I don't think the temps would get so high

built91Z28

Well if your fan isn't coming on, then thats your problem. No thermostat will fix that. Does it come on every time if you turn the AC on?

FooFighters92

iTrader: (2)

I'm in the process of gathering up everything to fix my a/c at the moment. As of now it doesn't work

ATCFLYBOY02

iTrader: (1)

I've always ran a 160 in all of the SBCs I've ever built (over 100 to date) and I will never use anything else on a gas engine... Now, we just got finished building my brothers 99 F250 w/ a 12v Cummins in it and we couldnt get it to run correctly w/ anything less than a 190* in it... But thats a diesel engine too...

Holliman48

I have an 85 Am. I run a 180 T-stat and Hypertech 4028 (off @ 185, on @ 200). So far my car hasn't been past the second mark on my temperature gauge. I live in Oregon, been about 90 somin the past few weeks.

vwdave

I cant get my 12v to run hotter than 160 lol.

IROCZ1989

iTrader: (1)

Been beat to death run a 180. You lose power and increase wear running colder. Best temp for wear and power 190-200. Run this temp with closed cold air system you will be fine. Nascar runs these temps reserch it. Oil needs to be 300°to proberly lubricate. Early on fan switches and cool thermostats just fool the ecm into throwing more timing at the motor, thats where people are fooled. Motors are designed to run these temps for complete combustion and wear characteristics. Stay away from fancy units, stant superstat from napa is a good buy.Sealed cold air system and these temps you will be on the right track. Take care.

IROCZ1989

iTrader: (1)

http://www.vincihiperformance.com/LS...amshaft%20Life!

Scroll down to proper coolent temp and camshaft wear.

Good link to read...

TTOP350

iTrader: (8)

160* t-stat in all my fun cars.
SAME mpg as my daily car with a 195 t-stat.
SAME factory recommended plugs (for corvette because of aluminum heads)
guess I should slow my car down at the track with a hotter plug than factory and more heat??
Just because the coolant temp is 160* doesn't mean your oil temp or exhaust temp is that cold.
Oil temp over 220 is a bit much for me. Water boils at 212* at sea level and less the higher you go.
Why on earth would you want to run your oil at close to 300degs!?!?!?!?!?!
If you drive your car in the winter and your skinny, you may want a 195 t-stat.
160-220 is a "normal" temp to run these engines. You WILL go faster at the track with a cooler motor an warm oil, proven over and over.......

DeathStarr89

iTrader: (1)

100% agreed.

I'd like to also add, the temp gauge in all of the 3rd gens i've owned over the years has never been right. My current 89 shows a little past 220 when it's actually 180.

I used the fan 2 output from the ECM to trigger the Temp light in the cluster at 180, works like a charm.

IROCZ1989

iTrader: (1)

Really?
Do you even know the ° range between each plug? Its 600. Thats why you drop 1-2 stages using nitrous or superchager using moderate boost and no2 Levels. You only put a hotter plug in your motor if the build calls for it not for more heat in the chamber.

Yes when your coolent temp in lower it is pulling heat out of the chamber on the compression stroke . Oil needs to be a certain temp to properly lubricate and cool as it does double duty. Thicker oil is colder oil.

Water boils at 212 but the added pressure of the closed coolent system plus the addition of anrifreeze raises this. 1lb of pressure raises boiling point about 3-4 degrees. So your 16lb factory cap raises the boiling point to 260. Now thats with 50/50 mix. It goes higher with more % of coolent. Thats why its plain dumb to run straight water and a 160 thermostat like most think is the best solution to a problem they think they have like running a 200° engine temp which is normal.

Faster at the track yes but only 1/4 mile runs where cold is king.

Here is the lowdown. For a majority here who have daily drivers or pleasure cars and want them to last, how ever you want to run the engine to get the proper temp 180-200 is perfectly fine no colder. What you want is the absolute coldest intake charge with the proper engine temps. Will make the most power and wear the least. Take care.

TTOP350

iTrader: (8)

Yes I understand plug temps and the reasons for them as I have been working on, plus building performance cars for about 35yrs.
To this statement, "guess I should slow my car down at the track with a hotter plug than factory and more heat??" I 4got to add "with a 195 t-stat"
I read the link you posted to that guys opinions, heres some other opinions.

The whole water boiling out of the oil is kind of silly really because the water vapor in oil is looong gone b4 the oil has to reach the majic 212 degs anyway due to the pistons heating up and helping burn it out.

90% of engine wear is at startup, not because it runs down the road at 160* water temp.
In recent years, lower friction rings, roller cams and EFI have done 1000 times more to help prevent wear that running a warmer t-stat, (warmer t-stats are more for emissions).
There have been quite a few overheating problems caused by running to much coolant in your system. I used to run a 50/50 mix when I drove her in the cold, I now run about 10-20% coolant. (mine doesn't go out any more in the cold weatherand stays in a heated garage)
Strait water is really the best along with a additive to keep the rust away and seals lubed as long as your car never freezes. But we live in the real world and need the coolant for freeze protection in the winter more than for the summer usage.
And I semi agree if its a daily driver, leave it alone. Buut people want cheap go fast mods.
The reasons most big shops run a 180* t-stat?
1 reason is because the aluminum block (LS) cars pull a buttload of heat off of the cyl walls and need to be warmer. (iron blocks hold more heat in the cyls so they can run cooler an make the best pull the 1st time) Every aluminum LS motor that I have dyno'd made its best number on the 3rd pull with a lil warmer coolant/block than iron blocks.
Another is because the people that buy these cars want a lil more heat in the spring/fall with cooler weather.
Emissions is also a big reason the factory runs a warmer Tstat.
Its really just a comfort issue for the passengers if the car is DD.

Its only 20* from 180*- 160*. Whats the wear diff in the motor going to be, really? It has more to do with short trips and how many times you shut the car on and off.
I can tell you tho that your rubber hoses,belts an plastic items under your hood last a LOT longer with coated headers/exhaust and cooler water temps.

I'm babbling because of lack of sleep, sorry. I'll try and fix this up a bit 2maro.

RJ76FLORES76

love all the info

MikeT 88IROC350

I am currently running a 170 stat. And i have tried several different ones, even a 170 with some small holes drilled in it. That didnt work, car wouldnt warm up and i couldnt get any heat out of it. Like someone said above, TPIS tested these tpi motors, and concluded that 170 was the best temp for max power. and that was discovered YEARS ago. I think i got mine at a GM dealer.

Now in my '90 C4, i put in a Stant 180 T-stat. but it does have aluminum heads. I just dont like to run a TPI at 195. When i was growing up working on cars, all of them (SBC) had 180 t-stats. They only went to 195 in early 80s, when fuel injection came along, and higher emission standards.

Also, 160 might be too cool for things to happen from the ECM. I do my own chips, so i can change things for the cooler temps.

Well that is my take on engine cooling......

RJ76FLORES76

cool I just bought a 180 high flow stat from classic industries

luvofjah

iTrader: (2)

I had a 170.. when I got my EBL P4 Flash, Rbob recommended the 180, so I put that in...

For me, the best heat management tool was the air dam... without it the tunnel would get hot (even with dynamat), but with it, everything stays cool (even have jet hot coated Hooker 2055's)...

Rafael

Thirdgen89GTA

iTrader: (5)

I ran a 160° stat. Engine never got up to temp, not much heat in the cabin any time it wasn't scorching out. And on the highway it was cool a cucumber.

180°F with an oil cooler.

Ron U.S.M.C.

I asked myself what do I consider two low then what I thought was to high. Then shot for the middle.

Anything between 180* and 200* would be acceptable.

That's a 180* thermostat with a primary fan coming on at 180* and a secondary fan as back up coming on at 190*.

I have a engine oil cooler set to flow at 180* and a extra transmission cooler .

My gage is accurate and the car once warm and into closed loop stays in that range.

The only exception would be stuck in bad traffic. It has hit 220* but that's it.

KITT1983

iTrader: (3)

I run a 180 thermostat with my crossfire 305 v8

Biggd4355

My switch on the block quit working. Now I can't get the old switch out. Stripped. Is it feasible to put a y fitting on top where the temp sending switch is and have both temp and fan from that one spot?

Ron U.S.M.C.

They have come out with some new style bolt extractors.
That and some P B blaster should work.


= https://www.google.com/search?source...55...........0.

Biggd4355

the area is constricted, room to work is restricted. Do you know anyone that has removed a stripped one?

QuickStyle

jmd

iTrader: (4)

195 all year, every year.

Delco discontinued the 192.

3rdgenmaro

iTrader: (9)

yes you can if you have to. Can also get a thermostat housing that has a bung in it, and use it. Again, if you had to. Not the best location, but better than nothing.

Reid Fleming

iTrader: (2)

It really depends on your climate. The ironic thing is that living in Arizona or Florida, a 160° thermostat provides zero benefit, as the car will never be able to maintain 160° during the summer time. But living in Minnesota during the wintertime, the car will be pegged on 160° and you'll freeze your butt off the entire time. I live in south Texas and during summer months, the car runs at 190° on the highway and about 220° in city traffic. That's with a 180° thermostat that is wide open and staying open about 5 minutes after driving the car with both radiator fans running during city driving (they shut off on the highway)

My personal fav is the 180° thermostat. It's low enough that it gives a tiny performance boost compared to the 195° stat during summer/spring/fall while still allowing you "reasonable" heat during the wintertime. Winter to me means temps in the high 30's to mid 40's. If I drove in a place that saw temps below freezing outside, the 195° would be the way to go. I can definitely feel a difference in heater output with the 180° stat when the temps are in the 30's compared to other vehicles with a 195°.

180° feels like a house with electric baseboard heaters or a heat pump.
195° feels like a house with a natural gas furnace.

I asked a C4 Corvette owner to calculate instant fuel economy. (The 1980's C4 Vettes have digital fuel economy as well as digital coolant temp). The difference between 160 and 180 was 1.5 mpg. The difference between 180 and 195 was 0.5 mpg. Hotter coolant temp = better fuel mileage.

The benefits of a 170° could be seen on summer time only cars in mild climates. I can see why Lingenfelter liked these. I think they're based in Indiana, where cars actually could run at 170° during the summer.

But honestly, for the majority of us, the 180° is going to be the sweet spot. Why burn more gas, get worse heater output, and accelerate engine wear by purposely running the car too cold with a 160? And why bother with a 160 if you live in a sweltering hot climate where it will never get that cold?

One of the biggest power losses in terms of hot running cars are cars that run lean (high BLM's). The BLM's can usually keep the INT running around 128. But if your BLM's are in the 140+ range, the car will only lose more and more power as the engine gets hotter. We fool ourselves by throwing low temp fan switches and thermostats at the car. But we're just masking the problem of lean conditions. Vacuum leaks, fuel issues, ignition issues. They all make your car run leaner. My Blazer makes absolutely zero difference driving at 180° compared to driving at 195°. (It has a 195° thermostat) But the BLM's on it run +/- 5% (aprox 122-133 BLM with INT at 128)

Fast355

iTrader: (2)

I tend to favor 170*F thermostats. 180*F runs the engine too hot for me with iron heads. My 1997 Express van has a modified L31 350 Vortec in it. I run a massive 1-ton big block radiator and a Duramax mechanical fan blade on it. The crank pulley has a 25% underdrive on it. I run 176*F year round even with 6,000 lbs on the back of the trailer hitch. I have the factory in-radiator engine oil cooler and transmission cooler and an additional transmission cooler in front of the massive condenser. The only time it runs any warmer than 178*F is while sitting stationary at idle. The underdrive just doesn't turn the water pump or cooling fan fast enough to keep the engine cold.

The absolute hottest I have seen it run is 203*F, that was with 6,000 lbs on the trailer hitch, coming back from San Antonio on I-35, was crusing 65-70 mph on a 105*F with the trailer on the back, came up to a traffic jam that was dead stop, I put the transmission in Park and sat on the interstate for 30 minutes with the A/C blasting. It leveled out at 203*F after about 20 minutes. I was datalogging at the time. The absolute second that I put the transmission back into drive and started to rev the engine up to move forward the coolant temp started to plummet like a rock. Within 30 seconds of moving at 1,500-2,500 rpm the cooling fan clutch had disengaged and the coolant temp had stabilized back at 176-178*F. It is amazing how well the cooling system I have mismatched works for me.

Even my transmission runs cool, at 120-150*F if not idling. Hottest I have seen the transmission is around 200*F but I was working it very hard at low speeds with an unlocked converter. I was in Ohio with temps in the teens recently in the Express and it was running 176*F and I had to turn the heater on to low, with the temperature **** about 1/3 way from cold just to keep the van from burning me out of it.

FWIW I played with thermostats temps from 160*F to 205*F in my old G20 van with the TPI 305, trying t eek out the last bit of mileage and got better mileage keeping it in the 170-180*F range. Above 190*F on the stock tune you start to see alot of timing retard. Stock tune on a Vortec engine is also no different. By 210-230*F depending on the year or application you are seeing 4-6* retard from coolant temp alone and if you factor in the MAT/IAT being hotter from the hotter engine and engine compartment, it pulls even more. My old G20 van had the same exact radiator dimensions your 3rd gens runs except I picked up a double width core, ran no hotter than 185*F year round, even towing. I ran mid 2000s Nissan Altima 2.5 dual speed condenser fan motors in a slightly trimmed Nissan housing with a full shroud. Never had an issue staying cool. Airflow is not the problem really, it is radiator surface area that needs to be improved. The old G20 ran so cool that under PCM control with the a/c off, the fans rarely ever ran, and even when they did it was low-speed only. Running the 7730 TPI ECM it is easy to use the 2nd fan output on the ECM and control both fans with the ECM rather than a switch. I did retain the cylinder head temperature switch, to ground the the low speed relay just in case for backup should the ECM not turn the fans on.

IROCZ1989

iTrader: (1)

That graph is actually a copy out of a 70s car handbook. Just look at the ls motors. My 5.3 tahoe runs 210.

Fast355

iTrader: (2)

Just because they run them hot does not mean the best power is made running them that hot. I had a modern Hemi that had a 205°F stat stock. The difference between making a pass at 170°F and 205°F was nearly 2 tenths of a second in the 1/8 mile.

IROCZ1989

iTrader: (1)

You dont go by tenth you go by mph for a gain. More then likley the manifold was heat soaked.

articwhiteZ

iTrader: (56)

my Lingenfelter stage 5 383 Z28 came with from Lingenfelter was a 165 and that's with the stock rad and duel fans. the car in the summer never seen 200.
with 4.11 gears. or at the track with back to back runs... avg was 190 to 195 when racing.

shutting the car down the fans would run for about 4 to 6 mins before turning off...

3rdgenmaro

iTrader: (9)

Yes and no. It is designed to help the engine warm up. But once it opens it does nothing on how hot the car will actually get. That relies on the radiator, water pump, various other things, and the airflow across the radiator.

The thermostat is a very simple regulating valve. Once it goes full open, it no longer controls how hot the engine will get.

SbFormula

I've read the entire thread and it seems like the best option is what ever you believe!!!

Best of luck

Fast355

iTrader: (2)

Gained MPH too and ET plays a big role in testing for average power gains and response gains. Manifold is composite and hot lapping the truck had nearly identical time slips once it was up to temp. You won't make more power running hotter, just not going to happen.

chazman

iTrader: (4)

Haha! Sounds like it.

Personally, I don't drive my 3rd gens in the winter, but If I change the t-stat I go with a 160.