thermastat readings, help lower

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abodyhotrod

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heres what my stats read.
195 (used in the spring 70-85 degees) 185-210
195(summer 100+)200-215
180(in summer 100+) temp range 200- 220+
180 (in spring) 180-210
160(in summer) no good 220 +

i have heard of drilling two holes on a stat to help it breathe and ive heard of restricting the flow with a metered free flow stat.

the reason is every time my car hits 210 the car runs like a pos at the bottom. i think my feul is getting to hot but i'd for now just like to lower my running temp for the summer.

gonna try a 180 and wetter water this time any ideas other than. should i drill two breathers
 
I'd verify state of tune, fuel mix, etc. Most stats begin to open at a certain temp and are fully open at a higher temp.

The giggle valves or small holes in the stat are good for allowing air bubbles to be displaced out of the engine into the radiator where coolant top up will take care of the potential level loss. This makes sure the system is working as it should.

Running too low of a stat or none at all can cause heat issues. Essentially the same thing to varying degrees (depending on temp range of stat) happens. Let's look at the 160 in your example above. The engine and coolant start off cold. In this condition the stat is closed and allows the coolant to circulate in the engine absorbing heat. When the engine coolant side gets warm enough the stat starts to open until it reaches a certain temp when it is fully open. The coolant from the engine side now flows into the radiator and displaces the coolant that has been sitting in the radiator and essentially pushes or flows it into the engine. The design of the system works in that the lower temperature radiator coolant is now flowing into the engine and that lower temp now causes the stat to close again thus holding the lower temp coolant from the radiator in the engine to absorb heat. The hotter temp coolant that was initially in the engine is now being held in the radiator where the heat is transfered to the radiator fins and it has a chance to be cooled down by the fan and airflow with the car moving. Then the cycle starts all over when the engine side gets warm enough.

In the instance when the stat is too low as in the 160 above, the coolant is flowing out of the engine and into the radiator, BUT.....the coolant in the radiator has not been there a sufficient time to cool down below the min temp of the stat. So, as the system builds heat from start up (as all do), eventually the point is reached where the stat ends up staying open the entire time and not giving sufficient time for the coolant to "rest" in the radiator and transfer that heat to the cooling fins of the radiator to be cooled by air movement. The system just continues to flow in a big circle with little chance for the coolant to be cooled down by the radiator so it keeps building heat.

Hope that makes sense.

The numbers you list for the 195 do not look out of this world. It sounds like you cooling system with the 195 is working correctly. I think I'd just check everything over in general to ensure it is as it should be. If you have a fan clutch is it good, radiator fins not clogged, mix correct etc. I'd ensure you have a good radiator cap on the system as this helps control heat through pressure. I tend to run 13 to 16 pound caps depending on the car.

From there I'd honestly look, as I said, at the state of tune. Lean, timing, fuel supply etc. for your run issues.
 
abodyhotrod said:
heres what my stats read.
195 (used in the spring 70-85 degees) 185-210
195(summer 100+)200-215
180(in summer 100+) temp range 200- 220+
180 (in spring) 180-210
160(in summer) no good 220 +

i have heard of drilling two holes on a stat to help it breathe and ive heard of restricting the flow with a metered free flow stat.

the reason is every time my car hits 210 the car runs like a pos at the bottom. i think my feul is getting to hot but i'd for now just like to lower my running temp for the summer.

gonna try a 180 and wetter water this time any ideas other than. should i drill two breathers
Click to expand...

The 180 stat is good all year 'round. The hole in the stat just lets it burp air out when you fill the system...it won't help cool.

I would have a reputable shop flush and pressure test the rad, flush the block really good, use a 180 stat, and most importantly run a shrould. The shrould in my case made the most difference. I made my own...could'nt find one.

Also, make sure the heater core is not plugged. I took mine out since I only drive it in good weather.

DSCN0831 (Small).JPG
 
Thermostat is clearly not the problem. I too suggest you turn your focus to the radiater.
 
my rad is a good 4 core redone recently.air fuel is good to according to my wide band afr's . timing is at about 20 degrees initial and 34 total. thats just what my cam likes. one more my fan is a flex fan with a stock shroud. and an electric fan on the outside. as a pusher for traffic and slow speeds.

i really think my 195 did fine but i hate running my car 210+ in the summer she starts to run like crap.
 
Have you tried putting the stock fan back on ?

If you want a lighter fan,try a old Chrysler 4-blade fan. Lighter than a 6 or 7 blade fan.

You couldnt pay me to run a flex fan. They can flatten out and actually work against you, plus they are dangerous.
 
I agree with Johnny Dart. Chuck that flex fan.

I run a 3 core 22" stock radiator with a stock fan shroud, 160 thermostat, 50/50 mix of antifreeze and Red Line Waterwetter and the car runs 195 max in 95+ weather.
 
When you had your radiator recored, did they talk you in to running a higher than stock fin count? I've seen problems with this. Apparently the higher fin count doesn't cool as well. Just doesn't pass enough air.
 
Abodyhotrod are the readings you say taken from the gauge or an accurate infrared temp gun? Reason I ask is I thought mine was running hot according to the gauge but it really wasn't. I got a deal on a high quality infrared temp gun and was playing with it (you know how it is with a new toy) and decided to see if my gauge was accurate. I found it was 20 degrees off. All the while I thought it was running 200 degrees it was only 180. Might be worth your while checking just so you know.
 
I'd imagine that electric "pusher" fan is just restricting airflow at cruising speeds. You could try getting a good ol' 7-blade clutch fan and maybe use a smaller fan pulley to get good airflow at idle.
 
are you running a high flow pump and stat? you might be pushing the coolant through the radiator too fast and not letting it do its job. another thought is how good does the shroud work with that flex fan? if it has a huge gap and the fan is set too far from the radiator it might not be pulling the air pass the radiator well enough too.
 
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